From ba116655acf3f5d3a0fe877493bc5763570612d2 Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 10 Jun 2026 12:12:36 +0300
Subject: [PATCH 01/13] Uploads and transactional support

---
 CHANGELOG.md                |   7 ++
 README.md                   | 210 +++++++++++++++++++++++++++++++++++-
 src/LoopsClient.php         |   2 +
 src/Transactional.php       |  44 ++++++--
 src/Uploads.php             |  30 ++++++
 tests/TransactionalTest.php | 162 ++++++++++++++++++++++++++--
 tests/UploadsTest.php       |  70 ++++++++++++
 7 files changed, 507 insertions(+), 18 deletions(-)
 create mode 100644 src/Uploads.php
 create mode 100644 tests/UploadsTest.php

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 61028a4..02975af 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,10 @@
+## v3.1.0 - Jun 10, 2026
+
+Added support for image uploads and transactional email content management.
+
+- `uploads->create()` and `uploads->complete()` for the uploads API.
+- `transactional->create()`, `transactional->get()`, `transactional->update()`, `transactional->ensureDraft()`, and `transactional->publish()` for managing transactional emails.
+
 ## v3.0.0 - May 19, 2026
 
 Added support for dedicated sending IPs, themes, components, campaigns, and email messages.
diff --git a/README.md b/README.md
index 42399b7..20b4174 100644
--- a/README.md
+++ b/README.md
@@ -108,6 +108,13 @@ You can use custom contact properties in API calls. Please make sure to [add cus
 - [events->send()](#events-send)
 - [transactional->send()](#transactional-send)
 - [transactional->list()](#transactional-list)
+- [transactional->create()](#transactional-create)
+- [transactional->get()](#transactional-get)
+- [transactional->update()](#transactional-update)
+- [transactional->ensureDraft()](#transactional-ensuredraft)
+- [transactional->publish()](#transactional-publish)
+- [uploads->create()](#uploads-create)
+- [uploads->complete()](#uploads-complete)
 - [dedicatedSendingIps->list()](#dedicatedsendingips-list)
 - [themes->list()](#themes-list)
 - [themes->get()](#themes-get)
@@ -843,7 +850,7 @@ If there is a problem with the request, a descriptive error message will be retu
 
 ### transactional->list()
 
-Get a list of published transactional emails.
+Get a paginated list of transactional emails, most recently created first.
 
 [API Reference](https://loops.so/docs/api-reference/list-transactional-emails)
 
@@ -872,24 +879,36 @@ $result = $loops->transactional->list(per_page: 15);
     "perPage": 20,
     "totalPages": 2,
     "nextCursor": "clyo0q4wo01p59fsecyxqsh38",
-    "nextPage": "https://app.loops.so/api/v1/transactional?cursor=clyo0q4wo01p59fsecyxqsh38&perPage=20"
+    "nextPage": "https://app.loops.so/api/v1/transactional-emails?cursor=clyo0q4wo01p59fsecyxqsh38&perPage=20"
   },
   "data": [
     {
       "id": "clfn0k1yg001imo0fdeqg30i8",
-      "lastUpdated": "2023-11-06T17:48:07.249Z",
+      "name": "Welcome email",
+      "draftEmailMessageId": null,
+      "publishedEmailMessageId": "msg_abc123",
+      "createdAt": "2023-11-06T17:48:07.249Z",
+      "updatedAt": "2023-11-06T17:48:07.249Z",
       "dataVariables": []
     },
     {
       "id": "cll42l54f20i1la0lfooe3z12",
-      "lastUpdated": "2025-02-02T02:56:28.845Z",
+      "name": "Password reset",
+      "draftEmailMessageId": "msg_def456",
+      "publishedEmailMessageId": "msg_ghi789",
+      "createdAt": "2025-01-15T10:00:00.000Z",
+      "updatedAt": "2025-02-02T02:56:28.845Z",
       "dataVariables": [
         "confirmationUrl"
       ]
     },
     {
       "id": "clw6rbuwp01rmeiyndm80155l",
-      "lastUpdated": "2024-05-14T19:02:52.000Z",
+      "name": "Team invite",
+      "draftEmailMessageId": "msg_jkl012",
+      "publishedEmailMessageId": null,
+      "createdAt": "2024-05-14T19:02:52.000Z",
+      "updatedAt": "2024-05-14T19:02:52.000Z",
       "dataVariables": [
         "firstName",
         "lastName",
@@ -903,6 +922,187 @@ $result = $loops->transactional->list(per_page: 15);
 
 ---
 
+### transactional->create()
+
+Create a new transactional email. An empty draft email message is created automatically.
+
+[API Reference](https://loops.so/docs/api-reference/create-transactional-email)
+
+#### Parameters
+
+| Name    | Type   | Required | Notes                              |
+| ------- | ------ | -------- | ---------------------------------- |
+| `$name` | string | Yes      | The name of the transactional email. |
+
+#### Example
+
+```php
+$result = $loops->transactional->create(name: 'Welcome email');
+```
+
+#### Response
+
+```json
+{
+  "id": "txn_123",
+  "name": "Welcome email",
+  "draftEmailMessageId": "msg_123",
+  "draftEmailMessageContentRevisionId": "rev_123",
+  "publishedEmailMessageId": null,
+  "createdAt": "2025-01-01T00:00:00.000Z",
+  "updatedAt": "2025-01-01T00:00:00.000Z",
+  "dataVariables": []
+}
+```
+
+---
+
+### transactional->get()
+
+Get a single transactional email by ID.
+
+[API Reference](https://loops.so/docs/api-reference/get-transactional-email)
+
+#### Parameters
+
+| Name                | Type   | Required | Notes                            |
+| ------------------- | ------ | -------- | -------------------------------- |
+| `$transactional_id` | string | Yes      | The ID of the transactional email. |
+
+#### Example
+
+```php
+$result = $loops->transactional->get(transactional_id: 'txn_123');
+```
+
+---
+
+### transactional->update()
+
+Update a transactional email's name.
+
+[API Reference](https://loops.so/docs/api-reference/update-transactional-email)
+
+#### Parameters
+
+| Name                | Type   | Required | Notes                            |
+| ------------------- | ------ | -------- | -------------------------------- |
+| `$transactional_id` | string | Yes      | The ID of the transactional email. |
+| `$name`             | string | Yes      | The updated name.                |
+
+#### Example
+
+```php
+$result = $loops->transactional->update(
+  transactional_id: 'txn_123',
+  name: 'Updated welcome email'
+);
+```
+
+---
+
+### transactional->ensureDraft()
+
+Ensure a transactional email has a draft email message. If a draft already exists it is returned unchanged; otherwise a new empty draft is created.
+
+[API Reference](https://loops.so/docs/api-reference/ensure-transactional-email-draft)
+
+#### Parameters
+
+| Name                | Type   | Required | Notes                            |
+| ------------------- | ------ | -------- | -------------------------------- |
+| `$transactional_id` | string | Yes      | The ID of the transactional email. |
+
+#### Example
+
+```php
+$result = $loops->transactional->ensureDraft(transactional_id: 'txn_123');
+```
+
+---
+
+### transactional->publish()
+
+Publish the transactional email's current draft email message.
+
+[API Reference](https://loops.so/docs/api-reference/publish-transactional-email)
+
+#### Parameters
+
+| Name                | Type   | Required | Notes                            |
+| ------------------- | ------ | -------- | -------------------------------- |
+| `$transactional_id` | string | Yes      | The ID of the transactional email. |
+
+#### Example
+
+```php
+$result = $loops->transactional->publish(transactional_id: 'txn_123');
+```
+
+---
+
+### uploads->create()
+
+Request a pre-signed URL to upload an image asset. Upload the file with HTTP `PUT` to the returned `presignedUrl` using the same `Content-Type` and `Content-Length`, then call `uploads->complete()`.
+
+[API Reference](https://loops.so/docs/api-reference/create-upload)
+
+#### Parameters
+
+| Name              | Type    | Required | Notes                                                                                      |
+| ----------------- | ------- | -------- | ------------------------------------------------------------------------------------------ |
+| `$content_type`   | string  | Yes      | MIME type of the file (`image/jpeg`, `image/png`, `image/gif`, or `image/webp`).           |
+| `$content_length` | integer | Yes      | File size in bytes. Must be a positive integer no greater than 4,000,000.                  |
+
+#### Example
+
+```php
+$result = $loops->uploads->create(
+  content_type: 'image/png',
+  content_length: 102400
+);
+```
+
+#### Response
+
+```json
+{
+  "emailAssetId": "asset_123",
+  "presignedUrl": "https://example.com/upload"
+}
+```
+
+---
+
+### uploads->complete()
+
+Finalize an asset after the file has been uploaded to the pre-signed URL.
+
+[API Reference](https://loops.so/docs/api-reference/complete-upload)
+
+#### Parameters
+
+| Name  | Type   | Required | Notes                                                                 |
+| ----- | ------ | -------- | --------------------------------------------------------------------- |
+| `$id` | string | Yes      | The `emailAssetId` returned from `uploads->create()`.                  |
+
+#### Example
+
+```php
+$result = $loops->uploads->complete(id: 'asset_123');
+```
+
+#### Response
+
+```json
+{
+  "emailAssetId": "asset_123",
+  "finalUrl": "https://cdn.example.com/image.png"
+}
+```
+
+---
+
 ### dedicatedSendingIps->list()
 
 Get a list of Loops' dedicated sending IP addresses.
diff --git a/src/LoopsClient.php b/src/LoopsClient.php
index 84c505b..78e0326 100644
--- a/src/LoopsClient.php
+++ b/src/LoopsClient.php
@@ -18,6 +18,7 @@ class LoopsClient
   public Components $components;
   public Campaigns $campaigns;
   public EmailMessages $emailMessages;
+  public Uploads $uploads;
 
   public function __construct(string $api_key)
   {
@@ -41,6 +42,7 @@ public function __construct(string $api_key)
     $this->components = new Components(client: $this);
     $this->campaigns = new Campaigns(client: $this);
     $this->emailMessages = new EmailMessages(client: $this);
+    $this->uploads = new Uploads(client: $this);
   }
 
   /**
diff --git a/src/Transactional.php b/src/Transactional.php
index b7220d5..6e301e0 100644
--- a/src/Transactional.php
+++ b/src/Transactional.php
@@ -35,17 +35,47 @@ public function send(
         ]);
     }
 
-    public function list(?int $per_page = 20, ?string $cursor = null): mixed
+    public function list(?int $per_page = null, ?string $cursor = null): mixed
     {
-
-        $query = [
-            'per_page' => $per_page
-        ];
-        if ($cursor)
+        $query = [];
+        if ($per_page !== null) {
+            $query['perPage'] = $per_page;
+        }
+        if ($cursor) {
             $query['cursor'] = $cursor;
+        }
 
-        return $this->client->query(method: 'GET', endpoint: 'v1/transactional', options: [
+        return $this->client->query(method: 'GET', endpoint: 'v1/transactional-emails', options: [
             'query' => $query
         ]);
     }
+
+    public function create(string $name): mixed
+    {
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails', options: [
+            'json' => ['name' => $name]
+        ]);
+    }
+
+    public function get(string $transactional_id): mixed
+    {
+        return $this->client->query(method: 'GET', endpoint: 'v1/transactional-emails/' . $transactional_id);
+    }
+
+    public function update(string $transactional_id, string $name): mixed
+    {
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id, options: [
+            'json' => ['name' => $name]
+        ]);
+    }
+
+    public function ensureDraft(string $transactional_id): mixed
+    {
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id . '/draft');
+    }
+
+    public function publish(string $transactional_id): mixed
+    {
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id . '/publish');
+    }
 }
\ No newline at end of file
diff --git a/src/Uploads.php b/src/Uploads.php
new file mode 100644
index 0000000..0adcb85
--- /dev/null
+++ b/src/Uploads.php
@@ -0,0 +1,30 @@
+<?php
+
+namespace Loops;
+
+use Loops\LoopsClient;
+
+class Uploads
+{
+    private $client;
+
+    public function __construct(LoopsClient $client)
+    {
+        $this->client = $client;
+    }
+
+    public function create(string $content_type, int $content_length): mixed
+    {
+        return $this->client->query(method: 'POST', endpoint: 'v1/uploads', options: [
+            'json' => [
+                'contentType' => $content_type,
+                'contentLength' => $content_length,
+            ]
+        ]);
+    }
+
+    public function complete(string $id): mixed
+    {
+        return $this->client->query(method: 'POST', endpoint: 'v1/uploads/' . $id . '/complete');
+    }
+}
diff --git a/tests/TransactionalTest.php b/tests/TransactionalTest.php
index 6121b52..1c0ded2 100644
--- a/tests/TransactionalTest.php
+++ b/tests/TransactionalTest.php
@@ -105,7 +105,7 @@ public function testSendTransactional(): void
     $this->assertTrue($result['success']);
   }
 
-  public function testGetTransactionals(): void
+  public function testListTransactionals(): void
   {
     $per_page = 20;
     $cursor = 'clyo0q4wo01p59fsecyxqsh38';
@@ -115,11 +115,11 @@ public function testGetTransactionals(): void
       ->expects($this->once())
       ->method('get')
       ->with(
-        'v1/transactional',
+        'v1/transactional-emails',
         $this->callback(function ($options) use ($per_page, $cursor) {
           // Verify the query parameters are passed correctly
           return isset($options['query'])
-            && $options['query']['per_page'] === $per_page
+            && $options['query']['perPage'] === $per_page
             && $options['query']['cursor'] === $cursor;
         })
       )
@@ -132,13 +132,16 @@ public function testGetTransactionals(): void
             'perPage' => 20,
             'totalPages' => 2,
             'nextCursor' => 'clyo0q4wo01p59fsecyxqsh38',
-            'nextPage' => 'https://app.loops.so/api/v1/transactional?cursor=clyo0q4wo01p59fsecyxqsh38&perPage=20'
+            'nextPage' => 'https://app.loops.so/api/v1/transactional-emails?cursor=clyo0q4wo01p59fsecyxqsh38&perPage=20'
           ],
           'data' => [
             [
               'id' => 'clfn0k1yg001imo0fdeqg30i8',
               'name' => 'Welcome email',
-              'lastUpdated' => '2023-11-06T17:48:07.249Z',
+              'draftEmailMessageId' => null,
+              'publishedEmailMessageId' => 'msg_abc123',
+              'createdAt' => '2023-11-06T17:48:07.249Z',
+              'updatedAt' => '2023-11-06T17:48:07.249Z',
               'dataVariables' => []
             ]
           ]
@@ -169,7 +172,154 @@ public function testGetTransactionals(): void
     $this->assertNotEmpty($result['data']);
     $this->assertArrayHasKey('id', $result['data'][0]);
     $this->assertArrayHasKey('name', $result['data'][0]);
-    $this->assertArrayHasKey('lastUpdated', $result['data'][0]);
+    $this->assertArrayHasKey('draftEmailMessageId', $result['data'][0]);
+    $this->assertArrayHasKey('publishedEmailMessageId', $result['data'][0]);
+    $this->assertArrayHasKey('createdAt', $result['data'][0]);
+    $this->assertArrayHasKey('updatedAt', $result['data'][0]);
     $this->assertArrayHasKey('dataVariables', $result['data'][0]);
   }
+
+  public function testCreateTransactional(): void
+  {
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with(
+        'v1/transactional-emails',
+        $this->callback(function ($options) {
+          return $options['json']['name'] === 'Welcome email';
+        })
+      )
+      ->willReturn(new Response(
+        status: 201,
+        body: json_encode([
+          'id' => 'txn_123',
+          'name' => 'Welcome email',
+          'draftEmailMessageId' => 'msg_123',
+          'draftEmailMessageContentRevisionId' => 'rev_123',
+          'publishedEmailMessageId' => null,
+          'createdAt' => '2025-01-01T00:00:00.000Z',
+          'updatedAt' => '2025-01-01T00:00:00.000Z',
+          'dataVariables' => []
+        ])
+      ));
+
+    $result = $this->client->transactional->create(name: 'Welcome email');
+
+    $this->assertEquals('txn_123', $result['id']);
+    $this->assertEquals('msg_123', $result['draftEmailMessageId']);
+  }
+
+  public function testGetTransactional(): void
+  {
+    $transactionalId = 'txn_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('get')
+      ->with('v1/transactional-emails/' . $transactionalId)
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'id' => $transactionalId,
+          'name' => 'Welcome email',
+          'draftEmailMessageId' => 'msg_123',
+          'publishedEmailMessageId' => 'msg_456',
+          'createdAt' => '2025-01-01T00:00:00.000Z',
+          'updatedAt' => '2025-01-01T00:00:00.000Z',
+          'dataVariables' => ['firstName']
+        ])
+      ));
+
+    $result = $this->client->transactional->get(transactional_id: $transactionalId);
+
+    $this->assertEquals($transactionalId, $result['id']);
+  }
+
+  public function testUpdateTransactional(): void
+  {
+    $transactionalId = 'txn_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with(
+        'v1/transactional-emails/' . $transactionalId,
+        $this->callback(function ($options) {
+          return $options['json']['name'] === 'Updated welcome email';
+        })
+      )
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'id' => $transactionalId,
+          'name' => 'Updated welcome email',
+          'draftEmailMessageId' => 'msg_123',
+          'publishedEmailMessageId' => null,
+          'createdAt' => '2025-01-01T00:00:00.000Z',
+          'updatedAt' => '2025-01-02T00:00:00.000Z',
+          'dataVariables' => []
+        ])
+      ));
+
+    $result = $this->client->transactional->update(
+      transactional_id: $transactionalId,
+      name: 'Updated welcome email'
+    );
+
+    $this->assertEquals('Updated welcome email', $result['name']);
+  }
+
+  public function testEnsureDraftTransactional(): void
+  {
+    $transactionalId = 'txn_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with('v1/transactional-emails/' . $transactionalId . '/draft')
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'id' => $transactionalId,
+          'name' => 'Welcome email',
+          'draftEmailMessageId' => 'msg_123',
+          'draftEmailMessageContentRevisionId' => 'rev_123',
+          'publishedEmailMessageId' => 'msg_456',
+          'createdAt' => '2025-01-01T00:00:00.000Z',
+          'updatedAt' => '2025-01-02T00:00:00.000Z',
+          'dataVariables' => []
+        ])
+      ));
+
+    $result = $this->client->transactional->ensureDraft(transactional_id: $transactionalId);
+
+    $this->assertEquals('msg_123', $result['draftEmailMessageId']);
+  }
+
+  public function testPublishTransactional(): void
+  {
+    $transactionalId = 'txn_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with('v1/transactional-emails/' . $transactionalId . '/publish')
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'id' => $transactionalId,
+          'name' => 'Welcome email',
+          'draftEmailMessageId' => null,
+          'publishedEmailMessageId' => 'msg_123',
+          'createdAt' => '2025-01-01T00:00:00.000Z',
+          'updatedAt' => '2025-01-02T00:00:00.000Z',
+          'dataVariables' => ['firstName']
+        ])
+      ));
+
+    $result = $this->client->transactional->publish(transactional_id: $transactionalId);
+
+    $this->assertEquals('msg_123', $result['publishedEmailMessageId']);
+  }
 }
\ No newline at end of file
diff --git a/tests/UploadsTest.php b/tests/UploadsTest.php
new file mode 100644
index 0000000..9ff50c0
--- /dev/null
+++ b/tests/UploadsTest.php
@@ -0,0 +1,70 @@
+<?php
+
+namespace Tests;
+
+use Loops\LoopsClient;
+use PHPUnit\Framework\TestCase;
+use GuzzleHttp\Psr7\Response;
+
+class UploadsTest extends TestCase
+{
+  private LoopsClient $client;
+  private \GuzzleHttp\Client $mockHttpClient;
+
+  protected function setUp(): void
+  {
+    $this->mockHttpClient = $this->createMock(\GuzzleHttp\Client::class);
+    $this->client = new LoopsClient('test_api_key');
+    $this->client->setHttpClient($this->mockHttpClient);
+  }
+
+  public function testCreateUpload(): void
+  {
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with(
+        'v1/uploads',
+        $this->callback(function ($options) {
+          return $options['json']['contentType'] === 'image/png'
+            && $options['json']['contentLength'] === 102400;
+        })
+      )
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'emailAssetId' => 'asset_123',
+          'presignedUrl' => 'https://example.com/upload'
+        ])
+      ));
+
+    $result = $this->client->uploads->create(
+      content_type: 'image/png',
+      content_length: 102400
+    );
+
+    $this->assertEquals('asset_123', $result['emailAssetId']);
+    $this->assertEquals('https://example.com/upload', $result['presignedUrl']);
+  }
+
+  public function testCompleteUpload(): void
+  {
+    $assetId = 'asset_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with('v1/uploads/' . $assetId . '/complete')
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'emailAssetId' => $assetId,
+          'finalUrl' => 'https://cdn.example.com/image.png'
+        ])
+      ));
+
+    $result = $this->client->uploads->complete(id: $assetId);
+
+    $this->assertEquals('https://cdn.example.com/image.png', $result['finalUrl']);
+  }
+}

From 42329d615cc202df60a7ac6626e2ce1538d38e6e Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 10 Jun 2026 15:17:21 +0300
Subject: [PATCH 02/13] Single upload command

---
 CHANGELOG.md          |   2 +-
 README.md             |  48 +++---------------
 src/LoopsClient.php   |   5 ++
 src/Uploads.php       |  75 ++++++++++++++++++++++++++--
 tests/UploadsTest.php | 110 ++++++++++++++++++++++++++++--------------
 5 files changed, 160 insertions(+), 80 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 02975af..8ed45f8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,7 +2,7 @@
 
 Added support for image uploads and transactional email content management.
 
-- `uploads->create()` and `uploads->complete()` for the uploads API.
+- `uploads->upload()` for uploading images.
 - `transactional->create()`, `transactional->get()`, `transactional->update()`, `transactional->ensureDraft()`, and `transactional->publish()` for managing transactional emails.
 
 ## v3.0.0 - May 19, 2026
diff --git a/README.md b/README.md
index 20b4174..2a3c7e7 100644
--- a/README.md
+++ b/README.md
@@ -113,8 +113,7 @@ You can use custom contact properties in API calls. Please make sure to [add cus
 - [transactional->update()](#transactional-update)
 - [transactional->ensureDraft()](#transactional-ensuredraft)
 - [transactional->publish()](#transactional-publish)
-- [uploads->create()](#uploads-create)
-- [uploads->complete()](#uploads-complete)
+- [uploads->upload()](#uploads-upload)
 - [dedicatedSendingIps->list()](#dedicatedsendingips-list)
 - [themes->list()](#themes-list)
 - [themes->get()](#themes-get)
@@ -1041,55 +1040,24 @@ $result = $loops->transactional->publish(transactional_id: 'txn_123');
 
 ---
 
-### uploads->create()
+### uploads->upload()
 
-Request a pre-signed URL to upload an image asset. Upload the file with HTTP `PUT` to the returned `presignedUrl` using the same `Content-Type` and `Content-Length`, then call `uploads->complete()`.
+Upload an image asset for use in LMX email content. The returned `finalUrl` can be used in an `<Image>` tag in your [LMX content](https://loops.so/docs/creating-emails/lmx).
 
 [API Reference](https://loops.so/docs/api-reference/create-upload)
 
 #### Parameters
 
-| Name              | Type    | Required | Notes                                                                                      |
-| ----------------- | ------- | -------- | ------------------------------------------------------------------------------------------ |
-| `$content_type`   | string  | Yes      | MIME type of the file (`image/jpeg`, `image/png`, `image/gif`, or `image/webp`).           |
-| `$content_length` | integer | Yes      | File size in bytes. Must be a positive integer no greater than 4,000,000.                  |
+| Name    | Type   | Required | Notes                                                                                                           |
+| ------- | ------ | -------- | --------------------------------------------------------------------------------------------------------------- |
+| `$path` | string | Yes      | Path to an image file. Supported types: JPEG, PNG, GIF, and WebP. Maximum file size is 4,000,000 bytes (4 MB). |
 
 #### Example
 
 ```php
-$result = $loops->uploads->create(
-  content_type: 'image/png',
-  content_length: 102400
-);
-```
-
-#### Response
+$result = $loops->uploads->upload(path: '/path/to/image.png');
 
-```json
-{
-  "emailAssetId": "asset_123",
-  "presignedUrl": "https://example.com/upload"
-}
-```
-
----
-
-### uploads->complete()
-
-Finalize an asset after the file has been uploaded to the pre-signed URL.
-
-[API Reference](https://loops.so/docs/api-reference/complete-upload)
-
-#### Parameters
-
-| Name  | Type   | Required | Notes                                                                 |
-| ----- | ------ | -------- | --------------------------------------------------------------------- |
-| `$id` | string | Yes      | The `emailAssetId` returned from `uploads->create()`.                  |
-
-#### Example
-
-```php
-$result = $loops->uploads->complete(id: 'asset_123');
+$imageUrl = $result['finalUrl'];
 ```
 
 #### Response
diff --git a/src/LoopsClient.php b/src/LoopsClient.php
index 78e0326..a943690 100644
--- a/src/LoopsClient.php
+++ b/src/LoopsClient.php
@@ -56,6 +56,11 @@ public function setHttpClient(\GuzzleHttp\Client $client): void
     $this->httpClient = $client;
   }
 
+  public function getHttpClient(): \GuzzleHttp\Client
+  {
+    return $this->httpClient;
+  }
+
   /**
    * Performs an HTTP request to the Loops API
    *
diff --git a/src/Uploads.php b/src/Uploads.php
index 0adcb85..ad2723f 100644
--- a/src/Uploads.php
+++ b/src/Uploads.php
@@ -6,6 +6,23 @@
 
 class Uploads
 {
+    private const ALLOWED_MIME_TYPES = [
+        'image/jpeg',
+        'image/png',
+        'image/gif',
+        'image/webp',
+    ];
+
+    private const EXTENSION_MIME_TYPES = [
+        'jpg' => 'image/jpeg',
+        'jpeg' => 'image/jpeg',
+        'png' => 'image/png',
+        'gif' => 'image/gif',
+        'webp' => 'image/webp',
+    ];
+
+    private const MAX_BYTES = 4000000;
+
     private $client;
 
     public function __construct(LoopsClient $client)
@@ -13,18 +30,68 @@ public function __construct(LoopsClient $client)
         $this->client = $client;
     }
 
-    public function create(string $content_type, int $content_length): mixed
+    public function upload(string $path): mixed
     {
-        return $this->client->query(method: 'POST', endpoint: 'v1/uploads', options: [
+        if (!is_readable($path)) {
+            throw new \InvalidArgumentException(message: 'File not found or not readable: ' . $path);
+        }
+
+        $contents = file_get_contents(filename: $path);
+        $content_length = strlen(string: $contents);
+
+        if ($content_length === 0) {
+            throw new \InvalidArgumentException(message: 'File is empty: ' . $path);
+        }
+
+        if ($content_length > self::MAX_BYTES) {
+            throw new \InvalidArgumentException(message: 'File exceeds the maximum allowed size of 4,000,000 bytes.');
+        }
+
+        $content_type = $this->resolveContentType(path: $path);
+        if ($content_type === null) {
+            throw new \InvalidArgumentException(message: 'Unsupported image type. Supported types: JPEG, PNG, GIF, and WebP.');
+        }
+
+        $created = $this->client->query(method: 'POST', endpoint: 'v1/uploads', options: [
             'json' => [
                 'contentType' => $content_type,
                 'contentLength' => $content_length,
             ]
         ]);
+
+        $response = $this->client->getHttpClient()->put($created['presignedUrl'], [
+            'headers' => [
+                'Content-Type' => $content_type,
+                'Content-Length' => (string) $content_length,
+            ],
+            'body' => $contents,
+            'http_errors' => false,
+        ]);
+
+        if ($response->getStatusCode() >= 400) {
+            throw new \RuntimeException(
+                message: 'Failed to upload file to pre-signed URL. HTTP status: ' . $response->getStatusCode(),
+                code: $response->getStatusCode()
+            );
+        }
+
+        return $this->client->query(
+            method: 'POST',
+            endpoint: 'v1/uploads/' . $created['emailAssetId'] . '/complete'
+        );
     }
 
-    public function complete(string $id): mixed
+    private function resolveContentType(string $path): ?string
     {
-        return $this->client->query(method: 'POST', endpoint: 'v1/uploads/' . $id . '/complete');
+        $finfo = finfo_open(flags: FILEINFO_MIME_TYPE);
+        $mime = finfo_file(finfo: $finfo, filename: $path);
+
+        if (in_array(needle: $mime, haystack: self::ALLOWED_MIME_TYPES, strict: true)) {
+            return $mime;
+        }
+
+        $extension = strtolower(string: pathinfo(path: $path, flags: PATHINFO_EXTENSION));
+
+        return self::EXTENSION_MIME_TYPES[$extension] ?? null;
     }
 }
diff --git a/tests/UploadsTest.php b/tests/UploadsTest.php
index 9ff50c0..fdbeb2e 100644
--- a/tests/UploadsTest.php
+++ b/tests/UploadsTest.php
@@ -10,61 +10,101 @@ class UploadsTest extends TestCase
 {
   private LoopsClient $client;
   private \GuzzleHttp\Client $mockHttpClient;
+  private string $imagePath;
 
   protected function setUp(): void
   {
     $this->mockHttpClient = $this->createMock(\GuzzleHttp\Client::class);
     $this->client = new LoopsClient('test_api_key');
     $this->client->setHttpClient($this->mockHttpClient);
+
+    $this->imagePath = sys_get_temp_dir() . '/loops_upload_test.png';
+    file_put_contents(
+      $this->imagePath,
+      base64_decode('iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8BQDwAEhQGAhKmMIQAAAABJRU5ErkJggg==')
+    );
+  }
+
+  protected function tearDown(): void
+  {
+    if (file_exists($this->imagePath)) {
+      unlink($this->imagePath);
+    }
   }
 
-  public function testCreateUpload(): void
+  public function testUpload(): void
   {
+    $presignedUrl = 'https://example.com/upload';
+    $assetId = 'asset_123';
+    $fileContents = file_get_contents($this->imagePath);
+    $contentLength = strlen($fileContents);
+
     $this->mockHttpClient
-      ->expects($this->once())
+      ->expects($this->exactly(2))
       ->method('post')
+      ->willReturnCallback(function ($endpoint, $options = []) use ($presignedUrl, $assetId, $contentLength) {
+        if ($endpoint === 'v1/uploads') {
+          $this->assertEquals('image/png', $options['json']['contentType']);
+          $this->assertEquals($contentLength, $options['json']['contentLength']);
+
+          return new Response(
+            status: 200,
+            body: json_encode([
+              'emailAssetId' => $assetId,
+              'presignedUrl' => $presignedUrl,
+            ])
+          );
+        }
+
+        if ($endpoint === 'v1/uploads/' . $assetId . '/complete') {
+          return new Response(
+            status: 200,
+            body: json_encode([
+              'emailAssetId' => $assetId,
+              'finalUrl' => 'https://cdn.example.com/image.png',
+            ])
+          );
+        }
+
+        $this->fail('Unexpected POST endpoint: ' . $endpoint);
+      });
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('put')
       ->with(
-        'v1/uploads',
-        $this->callback(function ($options) {
-          return $options['json']['contentType'] === 'image/png'
-            && $options['json']['contentLength'] === 102400;
+        $presignedUrl,
+        $this->callback(function ($options) use ($fileContents, $contentLength) {
+          return $options['headers']['Content-Type'] === 'image/png'
+            && $options['headers']['Content-Length'] === (string) $contentLength
+            && $options['body'] === $fileContents;
         })
       )
-      ->willReturn(new Response(
-        status: 200,
-        body: json_encode([
-          'emailAssetId' => 'asset_123',
-          'presignedUrl' => 'https://example.com/upload'
-        ])
-      ));
-
-    $result = $this->client->uploads->create(
-      content_type: 'image/png',
-      content_length: 102400
-    );
+      ->willReturn(new Response(status: 200));
 
-    $this->assertEquals('asset_123', $result['emailAssetId']);
-    $this->assertEquals('https://example.com/upload', $result['presignedUrl']);
+    $result = $this->client->uploads->upload(path: $this->imagePath);
+
+    $this->assertEquals($assetId, $result['emailAssetId']);
+    $this->assertEquals('https://cdn.example.com/image.png', $result['finalUrl']);
   }
 
-  public function testCompleteUpload(): void
+  public function testUploadRejectsMissingFile(): void
   {
-    $assetId = 'asset_123';
+    $this->expectException(\InvalidArgumentException::class);
 
-    $this->mockHttpClient
-      ->expects($this->once())
-      ->method('post')
-      ->with('v1/uploads/' . $assetId . '/complete')
-      ->willReturn(new Response(
-        status: 200,
-        body: json_encode([
-          'emailAssetId' => $assetId,
-          'finalUrl' => 'https://cdn.example.com/image.png'
-        ])
-      ));
+    $this->client->uploads->upload(path: '/path/does/not/exist.png');
+  }
 
-    $result = $this->client->uploads->complete(id: $assetId);
+  public function testUploadRejectsUnsupportedType(): void
+  {
+    $path = sys_get_temp_dir() . '/loops_upload_test.txt';
+    file_put_contents($path, 'not an image');
 
-    $this->assertEquals('https://cdn.example.com/image.png', $result['finalUrl']);
+    try {
+      $this->expectException(\InvalidArgumentException::class);
+      $this->client->uploads->upload(path: $path);
+    } finally {
+      unlink($path);
+    }
   }
 }

From 2544013112a45767b52c379729ce654971a86d2c Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 24 Jun 2026 12:42:17 +0300
Subject: [PATCH 03/13] OpenAPI spec 1.14.0

---
 CHANGELOG.md                      |  11 +-
 README.md                         | 452 ++++++++++++++++++++++++++----
 src/AudienceSegments.php          |  35 +++
 src/CampaignGroups.php            |  62 ++++
 src/Campaigns.php                 |  68 ++++-
 src/Components.php                |   4 +-
 src/EmailMessages.php             |  31 +-
 src/LoopsClient.php               |   8 +
 src/Themes.php                    |   4 +-
 src/Transactional.php             |  20 +-
 src/TransactionalGroups.php       |  62 ++++
 src/Workflows.php                 |  40 +++
 tests/AudienceSegmentsTest.php    |  66 +++++
 tests/CampaignGroupsTest.php      |  68 +++++
 tests/CampaignsTest.php           |   4 +-
 tests/ComponentsTest.php          |   2 +-
 tests/EmailMessagesTest.php       |  35 ++-
 tests/ThemesTest.php              |   2 +-
 tests/TransactionalGroupsTest.php |  57 ++++
 tests/TransactionalTest.php       |  16 +-
 tests/WorkflowsTest.php           |  61 ++++
 21 files changed, 1011 insertions(+), 97 deletions(-)
 create mode 100644 src/AudienceSegments.php
 create mode 100644 src/CampaignGroups.php
 create mode 100644 src/TransactionalGroups.php
 create mode 100644 src/Workflows.php
 create mode 100644 tests/AudienceSegmentsTest.php
 create mode 100644 tests/CampaignGroupsTest.php
 create mode 100644 tests/TransactionalGroupsTest.php
 create mode 100644 tests/WorkflowsTest.php

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8ed45f8..c31599c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,9 +1,16 @@
-## v3.1.0 - Jun 10, 2026
+## v4.0.0 - Jun 24, 2026
 
-Added support for image uploads and transactional email content management.
+Added support for new content endpoints:
 
 - `uploads->upload()` for uploading images.
 - `transactional->create()`, `transactional->get()`, `transactional->update()`, `transactional->ensureDraft()`, and `transactional->publish()` for managing transactional emails.
+- `audienceSegments->list()` and `audienceSegments->get()` for audience segments.
+- `workflows->list()`, `workflows->get()`, and `workflows->getNode()` for reading workflows.
+- `campaignGroups->list()`, `campaignGroups->create()`, `campaignGroups->get()`, and `campaignGroups->update()` for campaign groups.
+- `transactionalGroups->list()`, `transactionalGroups->create()`, `transactionalGroups->get()`, and `transactionalGroups->update()` for transactional groups.
+- `emailMessages->preview()` for sending test email previews.
+- Extended `campaigns->create()` and `campaigns->update()` with audience, group, and scheduling fields.
+- Renamed primary resource ID parameters to `id` (for example, `transactional->get(id: '...')` instead of `transactional_id:`).
 
 ## v3.0.0 - May 19, 2026
 
diff --git a/README.md b/README.md
index 2a3c7e7..553d0b5 100644
--- a/README.md
+++ b/README.md
@@ -113,7 +113,6 @@ You can use custom contact properties in API calls. Please make sure to [add cus
 - [transactional->update()](#transactional-update)
 - [transactional->ensureDraft()](#transactional-ensuredraft)
 - [transactional->publish()](#transactional-publish)
-- [uploads->upload()](#uploads-upload)
 - [dedicatedSendingIps->list()](#dedicatedsendingips-list)
 - [themes->list()](#themes-list)
 - [themes->get()](#themes-get)
@@ -123,8 +122,23 @@ You can use custom contact properties in API calls. Please make sure to [add cus
 - [campaigns->create()](#campaigns-create)
 - [campaigns->get()](#campaigns-get)
 - [campaigns->update()](#campaigns-update)
+- [campaignGroups->list()](#campaigngroups-list)
+- [campaignGroups->create()](#campaigngroups-create)
+- [campaignGroups->get()](#campaigngroups-get)
+- [campaignGroups->update()](#campaigngroups-update)
+- [audienceSegments->list()](#audiencesegments-list)
+- [audienceSegments->get()](#audiencesegments-get)
+- [workflows->list()](#workflows-list)
+- [workflows->get()](#workflows-get)
+- [workflows->getNode()](#workflows-getnode)
 - [emailMessages->get()](#emailmessages-get)
 - [emailMessages->update()](#emailmessages-update)
+- [emailMessages->preview()](#emailmessages-preview)
+- [transactionalGroups->list()](#transactionalgroups-list)
+- [transactionalGroups->create()](#transactionalgroups-create)
+- [transactionalGroups->get()](#transactionalgroups-get)
+- [transactionalGroups->update()](#transactionalgroups-update)
+- [uploads->upload()](#uploads-upload)
 
 ---
 
@@ -202,7 +216,7 @@ $result = $loops->contacts->create(
 ```json
 {
   "success": true,
-  "id": "id_of_contact"
+  "id": "cll6b3i8901a9jx0oyktl2m4u"
 }
 ```
 
@@ -267,7 +281,7 @@ $result = $loops->contacts->update(
 ```json
 {
   "success": true,
-  "id": "id_of_contact"
+  "id": "cll6b3i8901a9jx0oyktl2m4u"
 }
 ```
 
@@ -762,7 +776,7 @@ Send a transactional email to a contact. [Learn about sending transactional emai
 
 | Name                             | Type    | Required | Notes                                                                                                                                                                                            |
 | -------------------------------- | ------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
-| `$transactional_id`              | string  | Yes      | The ID of the transactional email to send.                                                                                                                                                       |
+| `$id`                             | string  | Yes      | The ID of the transactional email to send.                                                                                                                                                       |
 | `$email`                         | string  | Yes      | The email address of the recipient.                                                                                                                                                              |
 | `$add_to_audience`               | boolean | No       | If `true`, a contact will be created in your audience using the `$email` value (if a matching contact doesn’t already exist).                                                                    |
 | `$data_variables`                | array   | No       | An array containing data as defined by the data variables added to the transactional email template.<br />Values can be of type `string` or `number`.                                            |
@@ -776,7 +790,7 @@ Send a transactional email to a contact. [Learn about sending transactional emai
 
 ```php
 $result = $loops->transactional->send(
-  transactional_id: 'clfq6dinn000yl70fgwwyp82l',
+  id: 'clfq6dinn000yl70fgwwyp82l',
   email: 'hello@gmail.com',
   data_variables: [
     'loginUrl' => 'https://myapp.com/login/',
@@ -785,7 +799,7 @@ $result = $loops->transactional->send(
 
 # Example with Idempotency-Key header
 $result = $loops->transactional->send(
-  transactional_id: 'clfq6dinn000yl70fgwwyp82l',
+  id: 'clfq6dinn000yl70fgwwyp82l',
   email: 'hello@gmail.com',
   data_variables: [
     'loginUrl' => 'https://myapp.com/login/',
@@ -797,7 +811,7 @@ $result = $loops->transactional->send(
 
 # Please contact us to enable attachments on your account.
 $result = $loops->transactional->send(
-  transactional_id: 'clfq6dinn000yl70fgwwyp82l',
+  id: 'clfq6dinn000yl70fgwwyp82l',
   email: 'hello@gmail.com',
   data_variables: [
     'loginUrl' => 'https://myapp.com/login/',
@@ -885,7 +899,7 @@ $result = $loops->transactional->list(per_page: 15);
       "id": "clfn0k1yg001imo0fdeqg30i8",
       "name": "Welcome email",
       "draftEmailMessageId": null,
-      "publishedEmailMessageId": "msg_abc123",
+      "publishedEmailMessageId": "cly8k3m0n0044jpx2bghepq45",
       "createdAt": "2023-11-06T17:48:07.249Z",
       "updatedAt": "2023-11-06T17:48:07.249Z",
       "dataVariables": []
@@ -893,8 +907,8 @@ $result = $loops->transactional->list(per_page: 15);
     {
       "id": "cll42l54f20i1la0lfooe3z12",
       "name": "Password reset",
-      "draftEmailMessageId": "msg_def456",
-      "publishedEmailMessageId": "msg_ghi789",
+      "draftEmailMessageId": "cla3r8s9t0422ua56iqovab01",
+      "publishedEmailMessageId": "clb4s9t0u0533vb67jrpwbc12",
       "createdAt": "2025-01-15T10:00:00.000Z",
       "updatedAt": "2025-02-02T02:56:28.845Z",
       "dataVariables": [
@@ -904,7 +918,7 @@ $result = $loops->transactional->list(per_page: 15);
     {
       "id": "clw6rbuwp01rmeiyndm80155l",
       "name": "Team invite",
-      "draftEmailMessageId": "msg_jkl012",
+      "draftEmailMessageId": "clc5t0u1v0644wc78ksqxcd23",
       "publishedEmailMessageId": null,
       "createdAt": "2024-05-14T19:02:52.000Z",
       "updatedAt": "2024-05-14T19:02:52.000Z",
@@ -943,10 +957,10 @@ $result = $loops->transactional->create(name: 'Welcome email');
 
 ```json
 {
-  "id": "txn_123",
+  "id": "clfq6dinn000yl70fgwwyp82l",
   "name": "Welcome email",
-  "draftEmailMessageId": "msg_123",
-  "draftEmailMessageContentRevisionId": "rev_123",
+  "draftEmailMessageId": "cly8k3m0n0044jpx2bghepq45",
+  "draftEmailMessageContentRevisionId": "clm9n4o6p0088lrz4dijslt67",
   "publishedEmailMessageId": null,
   "createdAt": "2025-01-01T00:00:00.000Z",
   "updatedAt": "2025-01-01T00:00:00.000Z",
@@ -966,12 +980,12 @@ Get a single transactional email by ID.
 
 | Name                | Type   | Required | Notes                            |
 | ------------------- | ------ | -------- | -------------------------------- |
-| `$transactional_id` | string | Yes      | The ID of the transactional email. |
+| `$id` | string | Yes      | The ID of the transactional email. |
 
 #### Example
 
 ```php
-$result = $loops->transactional->get(transactional_id: 'txn_123');
+$result = $loops->transactional->get(id: 'clfq6dinn000yl70fgwwyp82l');
 ```
 
 ---
@@ -986,14 +1000,14 @@ Update a transactional email's name.
 
 | Name                | Type   | Required | Notes                            |
 | ------------------- | ------ | -------- | -------------------------------- |
-| `$transactional_id` | string | Yes      | The ID of the transactional email. |
+| `$id` | string | Yes      | The ID of the transactional email. |
 | `$name`             | string | Yes      | The updated name.                |
 
 #### Example
 
 ```php
 $result = $loops->transactional->update(
-  transactional_id: 'txn_123',
+  id: 'clfq6dinn000yl70fgwwyp82l',
   name: 'Updated welcome email'
 );
 ```
@@ -1010,12 +1024,12 @@ Ensure a transactional email has a draft email message. If a draft already exist
 
 | Name                | Type   | Required | Notes                            |
 | ------------------- | ------ | -------- | -------------------------------- |
-| `$transactional_id` | string | Yes      | The ID of the transactional email. |
+| `$id` | string | Yes      | The ID of the transactional email. |
 
 #### Example
 
 ```php
-$result = $loops->transactional->ensureDraft(transactional_id: 'txn_123');
+$result = $loops->transactional->ensureDraft(id: 'clfq6dinn000yl70fgwwyp82l');
 ```
 
 ---
@@ -1030,12 +1044,12 @@ Publish the transactional email's current draft email message.
 
 | Name                | Type   | Required | Notes                            |
 | ------------------- | ------ | -------- | -------------------------------- |
-| `$transactional_id` | string | Yes      | The ID of the transactional email. |
+| `$id` | string | Yes      | The ID of the transactional email. |
 
 #### Example
 
 ```php
-$result = $loops->transactional->publish(transactional_id: 'txn_123');
+$result = $loops->transactional->publish(id: 'clfq6dinn000yl70fgwwyp82l');
 ```
 
 ---
@@ -1064,7 +1078,7 @@ $imageUrl = $result['finalUrl'];
 
 ```json
 {
-  "emailAssetId": "asset_123",
+  "emailAssetId": "clu1v4w6x0254tz42lrcwat45",
   "finalUrl": "https://cdn.example.com/image.png"
 }
 ```
@@ -1113,7 +1127,7 @@ List email themes.
 ```php
 $result = $loops->themes->list();
 
-$result = $loops->themes->list(per_page: 15, cursor: 'cursor123');
+$result = $loops->themes->list(per_page: 15, cursor: 'clyo0q4wo01p59fsecyxqsh38');
 ```
 
 ---
@@ -1128,12 +1142,12 @@ Get a single email theme by ID.
 
 | Name        | Type   | Required | Notes              |
 | ----------- | ------ | -------- | ------------------ |
-| `$theme_id` | string | Yes      | The ID of the theme. |
+| `$id` | string | Yes      | The ID of the theme. |
 
 #### Example
 
 ```php
-$result = $loops->themes->get(theme_id: 'theme_abc123');
+$result = $loops->themes->get(id: 'clo5p8q0r0132ntx6flkunw89');
 ```
 
 ---
@@ -1169,12 +1183,12 @@ Get a single email component by ID.
 
 | Name            | Type   | Required | Notes                   |
 | --------------- | ------ | -------- | ----------------------- |
-| `$component_id` | string | Yes      | The ID of the component. |
+| `$id` | string | Yes      | The ID of the component. |
 
 #### Example
 
 ```php
-$result = $loops->components->get(component_id: 'component_abc123');
+$result = $loops->components->get(id: 'clp6q9r1s0154ouy7gmlovx90');
 ```
 
 ---
@@ -1208,14 +1222,25 @@ Create a new draft campaign.
 
 #### Parameters
 
-| Name    | Type   | Required | Notes              |
-| ------- | ------ | -------- | ------------------ |
-| `$name` | string | Yes      | The campaign name. |
+| Name                    | Type   | Required | Notes                                                                                                 |
+| ----------------------- | ------ | -------- | ----------------------------------------------------------------------------------------------------- |
+| `$name`                 | string | Yes      | The campaign name.                                                                                    |
+| `$campaign_group_id`    | string | No       | The ID of the group to add this campaign to.                                                          |
+| `$mailing_list_id`      | string | No       | The ID of the mailing list to send to.                                                                |
+| `$audience_segment_id`  | string | No       | The ID of an audience segment. Setting this clears any `audience_filter`.                             |
+| `$audience_filter`      | array  | No       | A tree of audience conditions. See the API reference for the filter schema.                           |
+| `$scheduling`           | array  | No       | When the campaign should send. Use `['method' => 'now']` or `['method' => 'schedule', 'timestamp' => '...']`. |
 
 #### Example
 
 ```php
 $result = $loops->campaigns->create(name: 'Spring announcement');
+
+$result = $loops->campaigns->create(
+  name: 'Spring announcement',
+  mailing_list_id: 'cm06f5v0e45nf0ml5754o9cix',
+  scheduling: ['method' => 'schedule', 'timestamp' => '2026-06-01T10:00:00Z']
+);
 ```
 
 #### Response
@@ -1223,13 +1248,13 @@ $result = $loops->campaigns->create(name: 'Spring announcement');
 ```json
 {
   "success": true,
-  "campaignId": "camp_123",
+  "campaignId": "cln4o7p9q0110msw5ekjtmv78",
   "name": "Spring announcement",
   "status": "Draft",
   "createdAt": "2025-01-01T00:00:00.000Z",
   "updatedAt": "2025-01-01T00:00:00.000Z",
-  "emailMessageId": "msg_123",
-  "emailMessageContentRevisionId": "rev_123"
+  "emailMessageId": "cly8k3m0n0044jpx2bghepq45",
+  "emailMessageContentRevisionId": "clm9n4o6p0088lrz4dijslt67"
 }
 ```
 
@@ -1243,42 +1268,244 @@ Get a single campaign by ID.
 
 #### Parameters
 
-| Name           | Type   | Required | Notes                 |
-| -------------- | ------ | -------- | --------------------- |
-| `$campaign_id` | string | Yes      | The ID of the campaign. |
+| Name                    | Type   | Required | Notes                 |
+| ----------------------- | ------ | -------- | --------------------- |
+| `$id`                   | string | Yes      | The ID of the campaign. |
 
 #### Example
 
 ```php
-$result = $loops->campaigns->get(campaign_id: 'camp_123');
+$result = $loops->campaigns->get(id: 'cln4o7p9q0110msw5ekjtmv78');
 ```
 
 ---
 
 ### campaigns->update()
 
-Update a draft campaign's name.
+Update a draft campaign's name, group, audience, or scheduling.
 
 [API Reference](https://loops.so/docs/api-reference/update-campaign)
 
 #### Parameters
 
-| Name           | Type   | Required | Notes                 |
-| -------------- | ------ | -------- | --------------------- |
-| `$campaign_id` | string | Yes      | The ID of the campaign. |
-| `$name`        | string | Yes      | The updated name.     |
+| Name                    | Type   | Required | Notes                                                                                                 |
+| ----------------------- | ------ | -------- | ----------------------------------------------------------------------------------------------------- |
+| `$id`                   | string | Yes      | The ID of the campaign.                                                                               |
+| `$name`                 | string | No       | The updated name.                                                                                     |
+| `$campaign_group_id`    | string | No       | The ID of the group to move this campaign to.                                                         |
+| `$mailing_list_id`      | string | No       | The ID of the mailing list to send to.                                                                |
+| `$audience_segment_id`  | string | No       | The ID of an audience segment. Setting this clears any `audience_filter`.                             |
+| `$audience_filter`      | array  | No       | A tree of audience conditions. See the API reference for the filter schema.                           |
+| `$scheduling`           | array  | No       | When the campaign should send. Use `['method' => 'now']` or `['method' => 'schedule', 'timestamp' => '...']`. |
+
+At least one field must be provided.
 
 #### Example
 
 ```php
 $result = $loops->campaigns->update(
-  campaign_id: 'camp_123',
+  id: 'cln4o7p9q0110msw5ekjtmv78',
+  name: 'Updated name'
+);
+```
+
+---
+
+### campaignGroups->list()
+
+List campaign groups.
+
+[API Reference](https://loops.so/docs/api-reference/list-campaign-groups)
+
+#### Parameters
+
+| Name        | Type    | Required | Notes                                                                                                                         |
+| ----------- | ------- | -------- | ----------------------------------------------------------------------------------------------------------------------------- |
+| `$per_page` | integer | No       | How many results to return per page. Must be between 10 and 50. Defaults to 20 if omitted.                                    |
+| `$cursor`   | string  | No       | A cursor, to return a specific page of results. Cursors can be found from the `pagination.nextCursor` value in each response. |
+
+#### Example
+
+```php
+$result = $loops->campaignGroups->list();
+```
+
+---
+
+### campaignGroups->create()
+
+Create a campaign group.
+
+[API Reference](https://loops.so/docs/api-reference/create-campaign-group)
+
+#### Parameters
+
+| Name            | Type   | Required | Notes                                   |
+| --------------- | ------ | -------- | --------------------------------------- |
+| `$name`         | string | Yes      | Cannot be the reserved name "Unsorted". |
+| `$description`  | string | No       | An optional description for the group.  |
+
+#### Example
+
+```php
+$result = $loops->campaignGroups->create(name: 'Newsletters', description: 'Monthly updates');
+```
+
+---
+
+### campaignGroups->get()
+
+Get a campaign group by ID.
+
+[API Reference](https://loops.so/docs/api-reference/get-campaign-group)
+
+#### Parameters
+
+| Name  | Type   | Required | Notes                        |
+| ----- | ------ | -------- | ---------------------------- |
+| `$id` | string | Yes      | The ID of the campaign group. |
+
+#### Example
+
+```php
+$result = $loops->campaignGroups->get(id: 'clq7r0s2t0176pvz8hnmpwy01');
+```
+
+---
+
+### campaignGroups->update()
+
+Update a campaign group's name or description.
+
+[API Reference](https://loops.so/docs/api-reference/update-campaign-group)
+
+#### Parameters
+
+| Name            | Type   | Required | Notes                                   |
+| --------------- | ------ | -------- | --------------------------------------- |
+| `$id`           | string | Yes      | The ID of the campaign group.           |
+| `$name`         | string | No       | Cannot be the reserved name "Unsorted". |
+| `$description`  | string | No       |                                         |
+
+At least one field must be provided.
+
+#### Example
+
+```php
+$result = $loops->campaignGroups->update(
+  id: 'clq7r0s2t0176pvz8hnmpwy01',
   name: 'Updated name'
 );
 ```
 
 ---
 
+### audienceSegments->list()
+
+List audience segments.
+
+[API Reference](https://loops.so/docs/api-reference/list-audience-segments)
+
+#### Parameters
+
+| Name        | Type    | Required | Notes                                                                                                                         |
+| ----------- | ------- | -------- | ----------------------------------------------------------------------------------------------------------------------------- |
+| `$per_page` | integer | No       | How many results to return per page. Must be between 10 and 50. Defaults to 20 if omitted.                                    |
+| `$cursor`   | string  | No       | A cursor, to return a specific page of results. Cursors can be found from the `pagination.nextCursor` value in each response. |
+
+#### Example
+
+```php
+$result = $loops->audienceSegments->list();
+```
+
+---
+
+### audienceSegments->get()
+
+Get an audience segment by ID.
+
+[API Reference](https://loops.so/docs/api-reference/get-audience-segment)
+
+#### Parameters
+
+| Name  | Type   | Required | Notes                           |
+| ----- | ------ | -------- | ------------------------------- |
+| `$id` | string | Yes      | The ID of the audience segment. |
+
+#### Example
+
+```php
+$result = $loops->audienceSegments->get(id: 'clr8s1t3u0198qw09iotqzx12');
+```
+
+---
+
+### workflows->list()
+
+List workflows.
+
+[API Reference](https://loops.so/docs/api-reference/list-workflows)
+
+#### Parameters
+
+| Name        | Type    | Required | Notes                                                                                                                         |
+| ----------- | ------- | -------- | ----------------------------------------------------------------------------------------------------------------------------- |
+| `$per_page` | integer | No       | How many results to return per page. Must be between 10 and 50. Defaults to 20 if omitted.                                    |
+| `$cursor`   | string  | No       | A cursor, to return a specific page of results. Cursors can be found from the `pagination.nextCursor` value in each response. |
+
+#### Example
+
+```php
+$result = $loops->workflows->list();
+```
+
+---
+
+### workflows->get()
+
+Get a simplified workflow graph.
+
+[API Reference](https://loops.so/docs/api-reference/get-workflow)
+
+#### Parameters
+
+| Name  | Type   | Required | Notes                  |
+| ----- | ------ | -------- | ---------------------- |
+| `$id` | string | Yes      | The ID of the workflow. |
+
+#### Example
+
+```php
+$result = $loops->workflows->get(id: 'cls9t2u4v0210rx20jpuary23');
+```
+
+---
+
+### workflows->getNode()
+
+Get detailed data for a single workflow node.
+
+[API Reference](https://loops.so/docs/api-reference/get-workflow-node)
+
+#### Parameters
+
+| Name            | Type   | Required | Notes                        |
+| --------------- | ------ | -------- | ---------------------------- |
+| `$workflow_id`  | string | Yes      | The ID of the workflow.      |
+| `$node_id`      | string | Yes      | The ID of the workflow node. |
+
+#### Example
+
+```php
+$result = $loops->workflows->getNode(
+  workflow_id: 'cls9t2u4v0210rx20jpuary23',
+  node_id: 'clt0u3v5w0232sy31kqvbzs34'
+);
+```
+
+---
+
 ### emailMessages->get()
 
 Get an email message, including its compiled LMX content.
@@ -1287,14 +1514,14 @@ Get an email message, including its compiled LMX content.
 
 #### Parameters
 
-| Name                | Type   | Required | Notes                       |
-| ------------------- | ------ | -------- | --------------------------- |
-| `$email_message_id` | string | Yes      | The ID of the email message. |
+| Name      | Type   | Required | Notes                       |
+| --------- | ------ | -------- | --------------------------- |
+| `$id`     | string | Yes      | The ID of the email message. |
 
 #### Example
 
 ```php
-$result = $loops->emailMessages->get(email_message_id: 'msg_123');
+$result = $loops->emailMessages->get(id: 'cly8k3m0n0044jpx2bghepq45');
 ```
 
 ---
@@ -1307,18 +1534,18 @@ Update an email message's subject, preview text, sender, or LMX content.
 
 #### Parameters
 
-| Name                | Type  | Required | Notes                                                                                                                                                                                                 |
-| ------------------- | ----- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| `$email_message_id` | string | Yes   | The ID of the email message.                                                                                                                                                                          |
-| `$fields`           | array | No       | Fields to update. Use API field names: `expectedRevisionId`, `subject`, `previewText`, `fromName`, `fromEmail`, `replyToEmail`, `lmx`. Supply `expectedRevisionId` matching the current `contentRevisionId` to avoid 409 conflicts. |
+| Name      | Type  | Required | Notes                                                                                                                                                                                                 |
+| --------- | ----- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| `$id`     | string | Yes   | The ID of the email message.                                                                                                                                                                          |
+| `$fields` | array | No       | Fields to update. Use API field names: `expectedRevisionId`, `subject`, `previewText`, `fromName`, `fromEmail`, `replyToEmail`, `lmx`. Supply `expectedRevisionId` matching the current `contentRevisionId` to avoid 409 conflicts. |
 
 #### Example
 
 ```php
 $result = $loops->emailMessages->update(
-  email_message_id: 'msg_123',
+  id: 'cly8k3m0n0044jpx2bghepq45',
   fields: [
-    'expectedRevisionId' => 'rev_123',
+    'expectedRevisionId' => 'clm9n4o6p0088lrz4dijslt67',
     'subject' => 'Updated subject',
     'lmx' => '<Email><Text>Hello</Text></Email>'
   ]
@@ -1327,6 +1554,123 @@ $result = $loops->emailMessages->update(
 
 ---
 
+### emailMessages->preview()
+
+Send a test preview of an email message to one or more addresses.
+
+[API Reference](https://loops.so/docs/api-reference/send-email-message-preview)
+
+#### Parameters
+
+| Name                   | Type     | Required | Notes                                                                             |
+| ---------------------- | -------- | -------- | --------------------------------------------------------------------------------- |
+| `$id`                  | string   | Yes      | The ID of the email message.                                                      |
+| `$emails`              | array    | Yes      | One or more addresses to send the preview to.                                     |
+| `$contact_properties`  | array    | No       | Contact property values to render. Accepted for campaign and workflow previews.   |
+| `$event_properties`    | array    | No       | Event property values to render. Accepted for workflow previews only.             |
+| `$data_variables`      | array    | No       | Transactional data variables to render. Accepted for transactional previews only. |
+
+#### Example
+
+```php
+$result = $loops->emailMessages->preview(
+  id: 'cly8k3m0n0044jpx2bghepq45',
+  emails: ['test@example.com'],
+  contact_properties: ['firstName' => 'Alex']
+);
+```
+
+---
+
+### transactionalGroups->list()
+
+List transactional groups.
+
+[API Reference](https://loops.so/docs/api-reference/list-transactional-groups)
+
+#### Parameters
+
+| Name        | Type    | Required | Notes                                                                                                                         |
+| ----------- | ------- | -------- | ----------------------------------------------------------------------------------------------------------------------------- |
+| `$per_page` | integer | No       | How many results to return per page. Must be between 10 and 50. Defaults to 20 if omitted.                                    |
+| `$cursor`   | string  | No       | A cursor, to return a specific page of results. Cursors can be found from the `pagination.nextCursor` value in each response. |
+
+#### Example
+
+```php
+$result = $loops->transactionalGroups->list();
+```
+
+---
+
+### transactionalGroups->create()
+
+Create a transactional group.
+
+[API Reference](https://loops.so/docs/api-reference/create-transactional-group)
+
+#### Parameters
+
+| Name            | Type   | Required | Notes                                   |
+| --------------- | ------ | -------- | --------------------------------------- |
+| `$name`         | string | Yes      | Cannot be the reserved name "Unsorted". |
+| `$description`  | string | No       | An optional description for the group.  |
+
+#### Example
+
+```php
+$result = $loops->transactionalGroups->create(name: 'Account emails');
+```
+
+---
+
+### transactionalGroups->get()
+
+Get a transactional group by ID.
+
+[API Reference](https://loops.so/docs/api-reference/get-transactional-group)
+
+#### Parameters
+
+| Name  | Type   | Required | Notes                             |
+| ----- | ------ | -------- | --------------------------------- |
+| `$id` | string | Yes      | The ID of the transactional group. |
+
+#### Example
+
+```php
+$result = $loops->transactionalGroups->get(id: 'clv2w3x4y0288xbb0kqrsuv67');
+```
+
+---
+
+### transactionalGroups->update()
+
+Update a transactional group's name or description.
+
+[API Reference](https://loops.so/docs/api-reference/update-transactional-group)
+
+#### Parameters
+
+| Name            | Type   | Required | Notes                                   |
+| --------------- | ------ | -------- | --------------------------------------- |
+| `$id`           | string | Yes      | The ID of the transactional group.      |
+| `$name`         | string | No       | Cannot be the reserved name "Unsorted". |
+| `$description`  | string | No       |                                         |
+
+At least one field must be provided.
+
+#### Example
+
+```php
+$result = $loops->transactionalGroups->update(
+  id: 'clv2w3x4y0288xbb0kqrsuv67',
+  name: 'Updated name'
+);
+```
+
+---
+
 ## Testing
 
 ```bash
diff --git a/src/AudienceSegments.php b/src/AudienceSegments.php
new file mode 100644
index 0000000..443e108
--- /dev/null
+++ b/src/AudienceSegments.php
@@ -0,0 +1,35 @@
+<?php
+
+namespace Loops;
+
+use Loops\LoopsClient;
+
+class AudienceSegments
+{
+    private $client;
+
+    public function __construct(LoopsClient $client)
+    {
+        $this->client = $client;
+    }
+
+    public function list(?int $per_page = null, ?string $cursor = null): mixed
+    {
+        $query = [];
+        if ($per_page !== null) {
+            $query['perPage'] = $per_page;
+        }
+        if ($cursor) {
+            $query['cursor'] = $cursor;
+        }
+
+        return $this->client->query(method: 'GET', endpoint: 'v1/audience-segments', options: [
+            'query' => $query
+        ]);
+    }
+
+    public function get(string $id): mixed
+    {
+        return $this->client->query(method: 'GET', endpoint: 'v1/audience-segments/' . $id);
+    }
+}
diff --git a/src/CampaignGroups.php b/src/CampaignGroups.php
new file mode 100644
index 0000000..ecb5bce
--- /dev/null
+++ b/src/CampaignGroups.php
@@ -0,0 +1,62 @@
+<?php
+
+namespace Loops;
+
+use Loops\LoopsClient;
+
+class CampaignGroups
+{
+    private $client;
+
+    public function __construct(LoopsClient $client)
+    {
+        $this->client = $client;
+    }
+
+    public function list(?int $per_page = null, ?string $cursor = null): mixed
+    {
+        $query = [];
+        if ($per_page !== null) {
+            $query['perPage'] = $per_page;
+        }
+        if ($cursor) {
+            $query['cursor'] = $cursor;
+        }
+
+        return $this->client->query(method: 'GET', endpoint: 'v1/campaign-groups', options: [
+            'query' => $query
+        ]);
+    }
+
+    public function create(string $name, ?string $description = null): mixed
+    {
+        $payload = ['name' => $name];
+        if ($description !== null) {
+            $payload['description'] = $description;
+        }
+
+        return $this->client->query(method: 'POST', endpoint: 'v1/campaign-groups', options: [
+            'json' => $payload
+        ]);
+    }
+
+    public function get(string $id): mixed
+    {
+        return $this->client->query(method: 'GET', endpoint: 'v1/campaign-groups/' . $id);
+    }
+
+    public function update(string $id, ?string $name = null, ?string $description = null): mixed
+    {
+        $payload = [];
+        if ($name !== null) {
+            $payload['name'] = $name;
+        }
+        if ($description !== null) {
+            $payload['description'] = $description;
+        }
+
+        return $this->client->query(method: 'POST', endpoint: 'v1/campaign-groups/' . $id, options: [
+            'json' => $payload
+        ]);
+    }
+}
diff --git a/src/Campaigns.php b/src/Campaigns.php
index e4d863c..caa1735 100644
--- a/src/Campaigns.php
+++ b/src/Campaigns.php
@@ -28,22 +28,72 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
         ]);
     }
 
-    public function create(string $name): mixed
-    {
+    public function create(
+        string $name,
+        ?string $campaign_group_id = null,
+        ?string $mailing_list_id = null,
+        ?string $audience_segment_id = null,
+        ?array $audience_filter = null,
+        ?array $scheduling = null
+    ): mixed {
+        $payload = ['name' => $name];
+        if ($campaign_group_id !== null) {
+            $payload['campaignGroupId'] = $campaign_group_id;
+        }
+        if ($mailing_list_id !== null) {
+            $payload['mailingListId'] = $mailing_list_id;
+        }
+        if ($audience_segment_id !== null) {
+            $payload['audienceSegmentId'] = $audience_segment_id;
+        }
+        if ($audience_filter !== null) {
+            $payload['audienceFilter'] = $audience_filter;
+        }
+        if ($scheduling !== null) {
+            $payload['scheduling'] = $scheduling;
+        }
+
         return $this->client->query(method: 'POST', endpoint: 'v1/campaigns', options: [
-            'json' => ['name' => $name]
+            'json' => $payload
         ]);
     }
 
-    public function get(string $campaign_id): mixed
+    public function get(string $id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/campaigns/' . $campaign_id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/campaigns/' . $id);
     }
 
-    public function update(string $campaign_id, string $name): mixed
-    {
-        return $this->client->query(method: 'POST', endpoint: 'v1/campaigns/' . $campaign_id, options: [
-            'json' => ['name' => $name]
+    public function update(
+        string $id,
+        ?string $name = null,
+        ?string $campaign_group_id = null,
+        ?string $mailing_list_id = null,
+        ?string $audience_segment_id = null,
+        ?array $audience_filter = null,
+        ?array $scheduling = null
+    ): mixed {
+        $payload = [];
+        if ($name !== null) {
+            $payload['name'] = $name;
+        }
+        if ($campaign_group_id !== null) {
+            $payload['campaignGroupId'] = $campaign_group_id;
+        }
+        if ($mailing_list_id !== null) {
+            $payload['mailingListId'] = $mailing_list_id;
+        }
+        if ($audience_segment_id !== null) {
+            $payload['audienceSegmentId'] = $audience_segment_id;
+        }
+        if ($audience_filter !== null) {
+            $payload['audienceFilter'] = $audience_filter;
+        }
+        if ($scheduling !== null) {
+            $payload['scheduling'] = $scheduling;
+        }
+
+        return $this->client->query(method: 'POST', endpoint: 'v1/campaigns/' . $id, options: [
+            'json' => $payload
         ]);
     }
 }
diff --git a/src/Components.php b/src/Components.php
index 9f38afa..18c368d 100644
--- a/src/Components.php
+++ b/src/Components.php
@@ -28,8 +28,8 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
         ]);
     }
 
-    public function get(string $component_id): mixed
+    public function get(string $id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/components/' . $component_id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/components/' . $id);
     }
 }
diff --git a/src/EmailMessages.php b/src/EmailMessages.php
index 6aa99b3..6ebdc01 100644
--- a/src/EmailMessages.php
+++ b/src/EmailMessages.php
@@ -13,15 +13,38 @@ public function __construct(LoopsClient $client)
         $this->client = $client;
     }
 
-    public function get(string $email_message_id): mixed
+    public function get(string $id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/email-messages/' . $email_message_id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/email-messages/' . $id);
     }
 
-    public function update(string $email_message_id, array $fields = []): mixed
+    public function update(string $id, array $fields = []): mixed
     {
-        return $this->client->query(method: 'POST', endpoint: 'v1/email-messages/' . $email_message_id, options: [
+        return $this->client->query(method: 'POST', endpoint: 'v1/email-messages/' . $id, options: [
             'json' => $fields
         ]);
     }
+
+    public function preview(
+        string $id,
+        array $emails,
+        ?array $contact_properties = null,
+        ?array $event_properties = null,
+        ?array $data_variables = null
+    ): mixed {
+        $payload = ['emails' => $emails];
+        if ($contact_properties !== null) {
+            $payload['contactProperties'] = $contact_properties;
+        }
+        if ($event_properties !== null) {
+            $payload['eventProperties'] = $event_properties;
+        }
+        if ($data_variables !== null) {
+            $payload['dataVariables'] = $data_variables;
+        }
+
+        return $this->client->query(method: 'POST', endpoint: 'v1/email-messages/' . $id . '/preview', options: [
+            'json' => $payload
+        ]);
+    }
 }
diff --git a/src/LoopsClient.php b/src/LoopsClient.php
index a943690..eac1d64 100644
--- a/src/LoopsClient.php
+++ b/src/LoopsClient.php
@@ -17,8 +17,12 @@ class LoopsClient
   public Themes $themes;
   public Components $components;
   public Campaigns $campaigns;
+  public CampaignGroups $campaignGroups;
   public EmailMessages $emailMessages;
   public Uploads $uploads;
+  public AudienceSegments $audienceSegments;
+  public Workflows $workflows;
+  public TransactionalGroups $transactionalGroups;
 
   public function __construct(string $api_key)
   {
@@ -41,8 +45,12 @@ public function __construct(string $api_key)
     $this->themes = new Themes(client: $this);
     $this->components = new Components(client: $this);
     $this->campaigns = new Campaigns(client: $this);
+    $this->campaignGroups = new CampaignGroups(client: $this);
     $this->emailMessages = new EmailMessages(client: $this);
     $this->uploads = new Uploads(client: $this);
+    $this->audienceSegments = new AudienceSegments(client: $this);
+    $this->workflows = new Workflows(client: $this);
+    $this->transactionalGroups = new TransactionalGroups(client: $this);
   }
 
   /**
diff --git a/src/Themes.php b/src/Themes.php
index 8c7d6e7..80c531d 100644
--- a/src/Themes.php
+++ b/src/Themes.php
@@ -28,8 +28,8 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
         ]);
     }
 
-    public function get(string $theme_id): mixed
+    public function get(string $id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/themes/' . $theme_id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/themes/' . $id);
     }
 }
diff --git a/src/Transactional.php b/src/Transactional.php
index 6e301e0..7219c00 100644
--- a/src/Transactional.php
+++ b/src/Transactional.php
@@ -14,7 +14,7 @@ public function __construct(LoopsClient $client)
     }
 
     public function send(
-        string $transactional_id,
+        string $id,
         string $email,
         ?bool $add_to_audience = false,
         ?array $data_variables = [],
@@ -22,7 +22,7 @@ public function send(
         ?array $headers = []
     ): mixed {
         $payload = [
-            'transactionalId' => $transactional_id,
+            'transactionalId' => $id,
             'email' => $email,
             'addToAudience' => $add_to_audience,
             'dataVariables' => $data_variables,
@@ -57,25 +57,25 @@ public function create(string $name): mixed
         ]);
     }
 
-    public function get(string $transactional_id): mixed
+    public function get(string $id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/transactional-emails/' . $transactional_id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/transactional-emails/' . $id);
     }
 
-    public function update(string $transactional_id, string $name): mixed
+    public function update(string $id, string $name): mixed
     {
-        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id, options: [
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $id, options: [
             'json' => ['name' => $name]
         ]);
     }
 
-    public function ensureDraft(string $transactional_id): mixed
+    public function ensureDraft(string $id): mixed
     {
-        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id . '/draft');
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $id . '/draft');
     }
 
-    public function publish(string $transactional_id): mixed
+    public function publish(string $id): mixed
     {
-        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id . '/publish');
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $id . '/publish');
     }
 }
\ No newline at end of file
diff --git a/src/TransactionalGroups.php b/src/TransactionalGroups.php
new file mode 100644
index 0000000..d5e856f
--- /dev/null
+++ b/src/TransactionalGroups.php
@@ -0,0 +1,62 @@
+<?php
+
+namespace Loops;
+
+use Loops\LoopsClient;
+
+class TransactionalGroups
+{
+    private $client;
+
+    public function __construct(LoopsClient $client)
+    {
+        $this->client = $client;
+    }
+
+    public function list(?int $per_page = null, ?string $cursor = null): mixed
+    {
+        $query = [];
+        if ($per_page !== null) {
+            $query['perPage'] = $per_page;
+        }
+        if ($cursor) {
+            $query['cursor'] = $cursor;
+        }
+
+        return $this->client->query(method: 'GET', endpoint: 'v1/transactional-groups', options: [
+            'query' => $query
+        ]);
+    }
+
+    public function create(string $name, ?string $description = null): mixed
+    {
+        $payload = ['name' => $name];
+        if ($description !== null) {
+            $payload['description'] = $description;
+        }
+
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-groups', options: [
+            'json' => $payload
+        ]);
+    }
+
+    public function get(string $id): mixed
+    {
+        return $this->client->query(method: 'GET', endpoint: 'v1/transactional-groups/' . $id);
+    }
+
+    public function update(string $id, ?string $name = null, ?string $description = null): mixed
+    {
+        $payload = [];
+        if ($name !== null) {
+            $payload['name'] = $name;
+        }
+        if ($description !== null) {
+            $payload['description'] = $description;
+        }
+
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-groups/' . $id, options: [
+            'json' => $payload
+        ]);
+    }
+}
diff --git a/src/Workflows.php b/src/Workflows.php
new file mode 100644
index 0000000..e74d570
--- /dev/null
+++ b/src/Workflows.php
@@ -0,0 +1,40 @@
+<?php
+
+namespace Loops;
+
+use Loops\LoopsClient;
+
+class Workflows
+{
+    private $client;
+
+    public function __construct(LoopsClient $client)
+    {
+        $this->client = $client;
+    }
+
+    public function list(?int $per_page = null, ?string $cursor = null): mixed
+    {
+        $query = [];
+        if ($per_page !== null) {
+            $query['perPage'] = $per_page;
+        }
+        if ($cursor) {
+            $query['cursor'] = $cursor;
+        }
+
+        return $this->client->query(method: 'GET', endpoint: 'v1/workflows', options: [
+            'query' => $query
+        ]);
+    }
+
+    public function get(string $id): mixed
+    {
+        return $this->client->query(method: 'GET', endpoint: 'v1/workflows/' . $id);
+    }
+
+    public function getNode(string $workflow_id, string $node_id): mixed
+    {
+        return $this->client->query(method: 'GET', endpoint: 'v1/workflows/' . $workflow_id . '/nodes/' . $node_id);
+    }
+}
diff --git a/tests/AudienceSegmentsTest.php b/tests/AudienceSegmentsTest.php
new file mode 100644
index 0000000..71c6e01
--- /dev/null
+++ b/tests/AudienceSegmentsTest.php
@@ -0,0 +1,66 @@
+<?php
+
+namespace Tests;
+
+use Loops\LoopsClient;
+use PHPUnit\Framework\TestCase;
+use GuzzleHttp\Psr7\Response;
+
+class AudienceSegmentsTest extends TestCase
+{
+  private LoopsClient $client;
+  private \GuzzleHttp\Client $mockHttpClient;
+
+  protected function setUp(): void
+  {
+    $this->mockHttpClient = $this->createMock(\GuzzleHttp\Client::class);
+    $this->client = new LoopsClient('test_api_key');
+    $this->client->setHttpClient($this->mockHttpClient);
+  }
+
+  public function testListAudienceSegments(): void
+  {
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('get')
+      ->with(
+        'v1/audience-segments',
+        $this->callback(function ($options) {
+          return $options['query']['perPage'] === 20
+            && $options['query']['cursor'] === 'cursor123';
+        })
+      )
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'pagination' => ['nextCursor' => null],
+          'data' => []
+        ])
+      ));
+
+    $result = $this->client->audienceSegments->list(per_page: 20, cursor: 'cursor123');
+
+    $this->assertEquals([], $result['data']);
+  }
+
+  public function testGetAudienceSegment(): void
+  {
+    $segmentId = 'seg_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('get')
+      ->with('v1/audience-segments/' . $segmentId)
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'id' => $segmentId,
+          'name' => 'Active subscribers'
+        ])
+      ));
+
+    $result = $this->client->audienceSegments->get(id: $segmentId);
+
+    $this->assertEquals($segmentId, $result['id']);
+  }
+}
diff --git a/tests/CampaignGroupsTest.php b/tests/CampaignGroupsTest.php
new file mode 100644
index 0000000..5048def
--- /dev/null
+++ b/tests/CampaignGroupsTest.php
@@ -0,0 +1,68 @@
+<?php
+
+namespace Tests;
+
+use Loops\LoopsClient;
+use PHPUnit\Framework\TestCase;
+use GuzzleHttp\Psr7\Response;
+
+class CampaignGroupsTest extends TestCase
+{
+  private LoopsClient $client;
+  private \GuzzleHttp\Client $mockHttpClient;
+
+  protected function setUp(): void
+  {
+    $this->mockHttpClient = $this->createMock(\GuzzleHttp\Client::class);
+    $this->client = new LoopsClient('test_api_key');
+    $this->client->setHttpClient($this->mockHttpClient);
+  }
+
+  public function testCreateCampaignGroup(): void
+  {
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with(
+        'v1/campaign-groups',
+        $this->callback(function ($options) {
+          return $options['json']['name'] === 'Newsletters'
+            && $options['json']['description'] === 'Monthly';
+        })
+      )
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode(['id' => 'grp_123', 'name' => 'Newsletters'])
+      ));
+
+    $result = $this->client->campaignGroups->create(name: 'Newsletters', description: 'Monthly');
+
+    $this->assertEquals('grp_123', $result['id']);
+  }
+
+  public function testUpdateCampaignGroup(): void
+  {
+    $groupId = 'grp_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with(
+        'v1/campaign-groups/' . $groupId,
+        $this->callback(function ($options) {
+          return $options['json']['name'] === 'Updated name';
+        })
+      )
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode(['id' => $groupId, 'name' => 'Updated name'])
+      ));
+
+    $result = $this->client->campaignGroups->update(
+      id: $groupId,
+      name: 'Updated name'
+    );
+
+    $this->assertEquals('Updated name', $result['name']);
+  }
+}
diff --git a/tests/CampaignsTest.php b/tests/CampaignsTest.php
index 39ee98d..5bf36ea 100644
--- a/tests/CampaignsTest.php
+++ b/tests/CampaignsTest.php
@@ -89,7 +89,7 @@ public function testFindCampaign(): void
         ])
       ));
 
-    $result = $this->client->campaigns->get(campaign_id: $campaignId);
+    $result = $this->client->campaigns->get(id: $campaignId);
 
     $this->assertEquals($campaignId, $result['campaignId']);
   }
@@ -121,7 +121,7 @@ public function testUpdateCampaign(): void
       ));
 
     $result = $this->client->campaigns->update(
-      campaign_id: $campaignId,
+      id: $campaignId,
       name: 'Updated name'
     );
 
diff --git a/tests/ComponentsTest.php b/tests/ComponentsTest.php
index b5f5ce0..8077f8a 100644
--- a/tests/ComponentsTest.php
+++ b/tests/ComponentsTest.php
@@ -58,7 +58,7 @@ public function testFindComponent(): void
         ])
       ));
 
-    $result = $this->client->components->get(component_id: $componentId);
+    $result = $this->client->components->get(id: $componentId);
 
     $this->assertEquals($componentId, $result['componentId']);
   }
diff --git a/tests/EmailMessagesTest.php b/tests/EmailMessagesTest.php
index 028db8c..e850b2b 100644
--- a/tests/EmailMessagesTest.php
+++ b/tests/EmailMessagesTest.php
@@ -43,7 +43,7 @@ public function testFindEmailMessage(): void
         ])
       ));
 
-    $result = $this->client->emailMessages->get(email_message_id: $emailMessageId);
+    $result = $this->client->emailMessages->get(id: $emailMessageId);
 
     $this->assertEquals($emailMessageId, $result['emailMessageId']);
   }
@@ -84,11 +84,42 @@ public function testUpdateEmailMessage(): void
       ));
 
     $result = $this->client->emailMessages->update(
-      email_message_id: $emailMessageId,
+      id: $emailMessageId,
       fields: $fields
     );
 
     $this->assertEquals('Updated subject', $result['subject']);
     $this->assertEquals('rev_456', $result['contentRevisionId']);
   }
+
+  public function testPreviewEmailMessage(): void
+  {
+    $emailMessageId = 'msg_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with(
+        'v1/email-messages/' . $emailMessageId . '/preview',
+        $this->callback(function ($options) {
+          return $options['json']['emails'] === ['test@example.com']
+            && $options['json']['contactProperties'] === ['firstName' => 'Ada'];
+        })
+      )
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'success' => true,
+          'emailMessageId' => $emailMessageId
+        ])
+      ));
+
+    $result = $this->client->emailMessages->preview(
+      id: $emailMessageId,
+      emails: ['test@example.com'],
+      contact_properties: ['firstName' => 'Ada']
+    );
+
+    $this->assertTrue($result['success']);
+  }
 }
diff --git a/tests/ThemesTest.php b/tests/ThemesTest.php
index b4995b6..f919dc0 100644
--- a/tests/ThemesTest.php
+++ b/tests/ThemesTest.php
@@ -65,7 +65,7 @@ public function testFindTheme(): void
         ])
       ));
 
-    $result = $this->client->themes->get(theme_id: $themeId);
+    $result = $this->client->themes->get(id: $themeId);
 
     $this->assertEquals($themeId, $result['themeId']);
   }
diff --git a/tests/TransactionalGroupsTest.php b/tests/TransactionalGroupsTest.php
new file mode 100644
index 0000000..f2d8b71
--- /dev/null
+++ b/tests/TransactionalGroupsTest.php
@@ -0,0 +1,57 @@
+<?php
+
+namespace Tests;
+
+use Loops\LoopsClient;
+use PHPUnit\Framework\TestCase;
+use GuzzleHttp\Psr7\Response;
+
+class TransactionalGroupsTest extends TestCase
+{
+  private LoopsClient $client;
+  private \GuzzleHttp\Client $mockHttpClient;
+
+  protected function setUp(): void
+  {
+    $this->mockHttpClient = $this->createMock(\GuzzleHttp\Client::class);
+    $this->client = new LoopsClient('test_api_key');
+    $this->client->setHttpClient($this->mockHttpClient);
+  }
+
+  public function testListTransactionalGroups(): void
+  {
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('get')
+      ->with('v1/transactional-groups')
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'pagination' => ['nextCursor' => null],
+          'data' => []
+        ])
+      ));
+
+    $result = $this->client->transactionalGroups->list();
+
+    $this->assertEquals([], $result['data']);
+  }
+
+  public function testGetTransactionalGroup(): void
+  {
+    $groupId = 'tgrp_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('get')
+      ->with('v1/transactional-groups/' . $groupId)
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode(['id' => $groupId, 'name' => 'Onboarding'])
+      ));
+
+    $result = $this->client->transactionalGroups->get(id: $groupId);
+
+    $this->assertEquals($groupId, $result['id']);
+  }
+}
diff --git a/tests/TransactionalTest.php b/tests/TransactionalTest.php
index 1c0ded2..bfd3b41 100644
--- a/tests/TransactionalTest.php
+++ b/tests/TransactionalTest.php
@@ -29,7 +29,7 @@ protected function setUp(): void
 
   public function testSendTransactional(): void
   {
-    $transactional_id = 'test_template_123';
+    $id = 'test_template_123';
     $email = 'test@example.com';
     $add_to_audience = true;
     $data_variables = ['name' => 'Test User'];
@@ -48,7 +48,7 @@ public function testSendTransactional(): void
       ->method('post')
       ->with(
         'v1/transactional',
-        $this->callback(function ($options) use ($transactional_id, $email, $add_to_audience, $data_variables, $attachments, $custom_headers) {
+        $this->callback(function ($options) use ($id, $email, $add_to_audience, $data_variables, $attachments, $custom_headers) {
           // Verify the request structure
           if (!isset($options['json']) || !isset($options['headers'])) {
             return false;
@@ -68,7 +68,7 @@ public function testSendTransactional(): void
             && isset($payload['attachments']);
 
           // Verify payload values
-          $has_correct_values = $payload['transactionalId'] === $transactional_id
+          $has_correct_values = $payload['transactionalId'] === $id
             && $payload['email'] === $email
             && $payload['addToAudience'] === $add_to_audience
             && $payload['dataVariables'] === $data_variables
@@ -89,7 +89,7 @@ public function testSendTransactional(): void
 
     // Make the API call
     $result = $this->client->transactional->send(
-      transactional_id: $transactional_id,
+      id: $id,
       email: $email,
       add_to_audience: $add_to_audience,
       data_variables: $data_variables,
@@ -231,7 +231,7 @@ public function testGetTransactional(): void
         ])
       ));
 
-    $result = $this->client->transactional->get(transactional_id: $transactionalId);
+    $result = $this->client->transactional->get(id: $transactionalId);
 
     $this->assertEquals($transactionalId, $result['id']);
   }
@@ -263,7 +263,7 @@ public function testUpdateTransactional(): void
       ));
 
     $result = $this->client->transactional->update(
-      transactional_id: $transactionalId,
+      id: $transactionalId,
       name: 'Updated welcome email'
     );
 
@@ -292,7 +292,7 @@ public function testEnsureDraftTransactional(): void
         ])
       ));
 
-    $result = $this->client->transactional->ensureDraft(transactional_id: $transactionalId);
+    $result = $this->client->transactional->ensureDraft(id: $transactionalId);
 
     $this->assertEquals('msg_123', $result['draftEmailMessageId']);
   }
@@ -318,7 +318,7 @@ public function testPublishTransactional(): void
         ])
       ));
 
-    $result = $this->client->transactional->publish(transactional_id: $transactionalId);
+    $result = $this->client->transactional->publish(id: $transactionalId);
 
     $this->assertEquals('msg_123', $result['publishedEmailMessageId']);
   }
diff --git a/tests/WorkflowsTest.php b/tests/WorkflowsTest.php
new file mode 100644
index 0000000..2269cd9
--- /dev/null
+++ b/tests/WorkflowsTest.php
@@ -0,0 +1,61 @@
+<?php
+
+namespace Tests;
+
+use Loops\LoopsClient;
+use PHPUnit\Framework\TestCase;
+use GuzzleHttp\Psr7\Response;
+
+class WorkflowsTest extends TestCase
+{
+  private LoopsClient $client;
+  private \GuzzleHttp\Client $mockHttpClient;
+
+  protected function setUp(): void
+  {
+    $this->mockHttpClient = $this->createMock(\GuzzleHttp\Client::class);
+    $this->client = new LoopsClient('test_api_key');
+    $this->client->setHttpClient($this->mockHttpClient);
+  }
+
+  public function testListWorkflows(): void
+  {
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('get')
+      ->with('v1/workflows')
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'pagination' => ['nextCursor' => null],
+          'data' => []
+        ])
+      ));
+
+    $result = $this->client->workflows->list();
+
+    $this->assertEquals([], $result['data']);
+  }
+
+  public function testGetWorkflowNode(): void
+  {
+    $workflowId = 'wf_123';
+    $nodeId = 'node_456';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('get')
+      ->with('v1/workflows/' . $workflowId . '/nodes/' . $nodeId)
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'id' => $nodeId,
+          'type' => 'email'
+        ])
+      ));
+
+    $result = $this->client->workflows->getNode(workflow_id: $workflowId, node_id: $nodeId);
+
+    $this->assertEquals($nodeId, $result['id']);
+  }
+}

From 3ca9728fc0f5d0188ce583bc816decd1f323e889 Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 24 Jun 2026 14:36:56 +0300
Subject: [PATCH 04/13] Revert ID name changes

---
 CHANGELOG.md                      |  1 -
 README.md                         | 76 +++++++++++++++----------------
 src/AudienceSegments.php          |  4 +-
 src/CampaignGroups.php            |  8 ++--
 src/Campaigns.php                 |  8 ++--
 src/Components.php                |  4 +-
 src/EmailMessages.php             | 12 ++---
 src/Themes.php                    |  4 +-
 src/Transactional.php             | 20 ++++----
 src/TransactionalGroups.php       |  8 ++--
 src/Workflows.php                 |  4 +-
 tests/AudienceSegmentsTest.php    |  2 +-
 tests/CampaignGroupsTest.php      |  2 +-
 tests/CampaignsTest.php           |  4 +-
 tests/ComponentsTest.php          |  2 +-
 tests/EmailMessagesTest.php       |  6 +--
 tests/ThemesTest.php              |  2 +-
 tests/TransactionalGroupsTest.php |  2 +-
 tests/TransactionalTest.php       | 16 +++----
 19 files changed, 92 insertions(+), 93 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index c31599c..8b18bce 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,7 +10,6 @@ Added support for new content endpoints:
 - `transactionalGroups->list()`, `transactionalGroups->create()`, `transactionalGroups->get()`, and `transactionalGroups->update()` for transactional groups.
 - `emailMessages->preview()` for sending test email previews.
 - Extended `campaigns->create()` and `campaigns->update()` with audience, group, and scheduling fields.
-- Renamed primary resource ID parameters to `id` (for example, `transactional->get(id: '...')` instead of `transactional_id:`).
 
 ## v3.0.0 - May 19, 2026
 
diff --git a/README.md b/README.md
index 553d0b5..893871f 100644
--- a/README.md
+++ b/README.md
@@ -776,7 +776,7 @@ Send a transactional email to a contact. [Learn about sending transactional emai
 
 | Name                             | Type    | Required | Notes                                                                                                                                                                                            |
 | -------------------------------- | ------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
-| `$id`                             | string  | Yes      | The ID of the transactional email to send.                                                                                                                                                       |
+| `$transactional_id`              | string  | Yes      | The ID of the transactional email to send.                                                                                                                                                       |
 | `$email`                         | string  | Yes      | The email address of the recipient.                                                                                                                                                              |
 | `$add_to_audience`               | boolean | No       | If `true`, a contact will be created in your audience using the `$email` value (if a matching contact doesn’t already exist).                                                                    |
 | `$data_variables`                | array   | No       | An array containing data as defined by the data variables added to the transactional email template.<br />Values can be of type `string` or `number`.                                            |
@@ -790,7 +790,7 @@ Send a transactional email to a contact. [Learn about sending transactional emai
 
 ```php
 $result = $loops->transactional->send(
-  id: 'clfq6dinn000yl70fgwwyp82l',
+  transactional_id: 'clfq6dinn000yl70fgwwyp82l',
   email: 'hello@gmail.com',
   data_variables: [
     'loginUrl' => 'https://myapp.com/login/',
@@ -799,7 +799,7 @@ $result = $loops->transactional->send(
 
 # Example with Idempotency-Key header
 $result = $loops->transactional->send(
-  id: 'clfq6dinn000yl70fgwwyp82l',
+  transactional_id: 'clfq6dinn000yl70fgwwyp82l',
   email: 'hello@gmail.com',
   data_variables: [
     'loginUrl' => 'https://myapp.com/login/',
@@ -811,7 +811,7 @@ $result = $loops->transactional->send(
 
 # Please contact us to enable attachments on your account.
 $result = $loops->transactional->send(
-  id: 'clfq6dinn000yl70fgwwyp82l',
+  transactional_id: 'clfq6dinn000yl70fgwwyp82l',
   email: 'hello@gmail.com',
   data_variables: [
     'loginUrl' => 'https://myapp.com/login/',
@@ -980,12 +980,12 @@ Get a single transactional email by ID.
 
 | Name                | Type   | Required | Notes                            |
 | ------------------- | ------ | -------- | -------------------------------- |
-| `$id` | string | Yes      | The ID of the transactional email. |
+| `$transactional_id` | string | Yes      | The ID of the transactional email. |
 
 #### Example
 
 ```php
-$result = $loops->transactional->get(id: 'clfq6dinn000yl70fgwwyp82l');
+$result = $loops->transactional->get(transactional_id: 'clfq6dinn000yl70fgwwyp82l');
 ```
 
 ---
@@ -1000,14 +1000,14 @@ Update a transactional email's name.
 
 | Name                | Type   | Required | Notes                            |
 | ------------------- | ------ | -------- | -------------------------------- |
-| `$id` | string | Yes      | The ID of the transactional email. |
+| `$transactional_id` | string | Yes      | The ID of the transactional email. |
 | `$name`             | string | Yes      | The updated name.                |
 
 #### Example
 
 ```php
 $result = $loops->transactional->update(
-  id: 'clfq6dinn000yl70fgwwyp82l',
+  transactional_id: 'clfq6dinn000yl70fgwwyp82l',
   name: 'Updated welcome email'
 );
 ```
@@ -1024,12 +1024,12 @@ Ensure a transactional email has a draft email message. If a draft already exist
 
 | Name                | Type   | Required | Notes                            |
 | ------------------- | ------ | -------- | -------------------------------- |
-| `$id` | string | Yes      | The ID of the transactional email. |
+| `$transactional_id` | string | Yes      | The ID of the transactional email. |
 
 #### Example
 
 ```php
-$result = $loops->transactional->ensureDraft(id: 'clfq6dinn000yl70fgwwyp82l');
+$result = $loops->transactional->ensureDraft(transactional_id: 'clfq6dinn000yl70fgwwyp82l');
 ```
 
 ---
@@ -1044,12 +1044,12 @@ Publish the transactional email's current draft email message.
 
 | Name                | Type   | Required | Notes                            |
 | ------------------- | ------ | -------- | -------------------------------- |
-| `$id` | string | Yes      | The ID of the transactional email. |
+| `$transactional_id` | string | Yes      | The ID of the transactional email. |
 
 #### Example
 
 ```php
-$result = $loops->transactional->publish(id: 'clfq6dinn000yl70fgwwyp82l');
+$result = $loops->transactional->publish(transactional_id: 'clfq6dinn000yl70fgwwyp82l');
 ```
 
 ---
@@ -1142,12 +1142,12 @@ Get a single email theme by ID.
 
 | Name        | Type   | Required | Notes              |
 | ----------- | ------ | -------- | ------------------ |
-| `$id` | string | Yes      | The ID of the theme. |
+| `$theme_id` | string | Yes      | The ID of the theme. |
 
 #### Example
 
 ```php
-$result = $loops->themes->get(id: 'clo5p8q0r0132ntx6flkunw89');
+$result = $loops->themes->get(theme_id: 'clo5p8q0r0132ntx6flkunw89');
 ```
 
 ---
@@ -1183,12 +1183,12 @@ Get a single email component by ID.
 
 | Name            | Type   | Required | Notes                   |
 | --------------- | ------ | -------- | ----------------------- |
-| `$id` | string | Yes      | The ID of the component. |
+| `$component_id` | string | Yes      | The ID of the component. |
 
 #### Example
 
 ```php
-$result = $loops->components->get(id: 'clp6q9r1s0154ouy7gmlovx90');
+$result = $loops->components->get(component_id: 'clp6q9r1s0154ouy7gmlovx90');
 ```
 
 ---
@@ -1270,12 +1270,12 @@ Get a single campaign by ID.
 
 | Name                    | Type   | Required | Notes                 |
 | ----------------------- | ------ | -------- | --------------------- |
-| `$id`                   | string | Yes      | The ID of the campaign. |
+| `$campaign_id`                 | string | Yes      | The ID of the campaign. |
 
 #### Example
 
 ```php
-$result = $loops->campaigns->get(id: 'cln4o7p9q0110msw5ekjtmv78');
+$result = $loops->campaigns->get(campaign_id: 'cln4o7p9q0110msw5ekjtmv78');
 ```
 
 ---
@@ -1290,7 +1290,7 @@ Update a draft campaign's name, group, audience, or scheduling.
 
 | Name                    | Type   | Required | Notes                                                                                                 |
 | ----------------------- | ------ | -------- | ----------------------------------------------------------------------------------------------------- |
-| `$id`                   | string | Yes      | The ID of the campaign.                                                                               |
+| `$campaign_id`                 | string | Yes      | The ID of the campaign.                                                                               |
 | `$name`                 | string | No       | The updated name.                                                                                     |
 | `$campaign_group_id`    | string | No       | The ID of the group to move this campaign to.                                                         |
 | `$mailing_list_id`      | string | No       | The ID of the mailing list to send to.                                                                |
@@ -1304,7 +1304,7 @@ At least one field must be provided.
 
 ```php
 $result = $loops->campaigns->update(
-  id: 'cln4o7p9q0110msw5ekjtmv78',
+  campaign_id: 'cln4o7p9q0110msw5ekjtmv78',
   name: 'Updated name'
 );
 ```
@@ -1363,12 +1363,12 @@ Get a campaign group by ID.
 
 | Name  | Type   | Required | Notes                        |
 | ----- | ------ | -------- | ---------------------------- |
-| `$id` | string | Yes      | The ID of the campaign group. |
+| `$campaign_group_id` | string | Yes      | The ID of the campaign group. |
 
 #### Example
 
 ```php
-$result = $loops->campaignGroups->get(id: 'clq7r0s2t0176pvz8hnmpwy01');
+$result = $loops->campaignGroups->get(campaign_group_id: 'clq7r0s2t0176pvz8hnmpwy01');
 ```
 
 ---
@@ -1383,7 +1383,7 @@ Update a campaign group's name or description.
 
 | Name            | Type   | Required | Notes                                   |
 | --------------- | ------ | -------- | --------------------------------------- |
-| `$id`           | string | Yes      | The ID of the campaign group.           |
+| `$campaign_group_id` | string | Yes      | The ID of the campaign group.           |
 | `$name`         | string | No       | Cannot be the reserved name "Unsorted". |
 | `$description`  | string | No       |                                         |
 
@@ -1393,7 +1393,7 @@ At least one field must be provided.
 
 ```php
 $result = $loops->campaignGroups->update(
-  id: 'clq7r0s2t0176pvz8hnmpwy01',
+  campaign_group_id: 'clq7r0s2t0176pvz8hnmpwy01',
   name: 'Updated name'
 );
 ```
@@ -1431,12 +1431,12 @@ Get an audience segment by ID.
 
 | Name  | Type   | Required | Notes                           |
 | ----- | ------ | -------- | ------------------------------- |
-| `$id` | string | Yes      | The ID of the audience segment. |
+| `$audience_segment_id` | string | Yes      | The ID of the audience segment. |
 
 #### Example
 
 ```php
-$result = $loops->audienceSegments->get(id: 'clr8s1t3u0198qw09iotqzx12');
+$result = $loops->audienceSegments->get(audience_segment_id: 'clr8s1t3u0198qw09iotqzx12');
 ```
 
 ---
@@ -1472,12 +1472,12 @@ Get a simplified workflow graph.
 
 | Name  | Type   | Required | Notes                  |
 | ----- | ------ | -------- | ---------------------- |
-| `$id` | string | Yes      | The ID of the workflow. |
+| `$workflow_id` | string | Yes      | The ID of the workflow. |
 
 #### Example
 
 ```php
-$result = $loops->workflows->get(id: 'cls9t2u4v0210rx20jpuary23');
+$result = $loops->workflows->get(workflow_id: 'cls9t2u4v0210rx20jpuary23');
 ```
 
 ---
@@ -1516,12 +1516,12 @@ Get an email message, including its compiled LMX content.
 
 | Name      | Type   | Required | Notes                       |
 | --------- | ------ | -------- | --------------------------- |
-| `$id`     | string | Yes      | The ID of the email message. |
+| `$email_message_id` | string | Yes      | The ID of the email message. |
 
 #### Example
 
 ```php
-$result = $loops->emailMessages->get(id: 'cly8k3m0n0044jpx2bghepq45');
+$result = $loops->emailMessages->get(email_message_id: 'cly8k3m0n0044jpx2bghepq45');
 ```
 
 ---
@@ -1536,14 +1536,14 @@ Update an email message's subject, preview text, sender, or LMX content.
 
 | Name      | Type  | Required | Notes                                                                                                                                                                                                 |
 | --------- | ----- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| `$id`     | string | Yes   | The ID of the email message.                                                                                                                                                                          |
+| `$email_message_id` | string | Yes   | The ID of the email message.                                                                                                                                                                          |
 | `$fields` | array | No       | Fields to update. Use API field names: `expectedRevisionId`, `subject`, `previewText`, `fromName`, `fromEmail`, `replyToEmail`, `lmx`. Supply `expectedRevisionId` matching the current `contentRevisionId` to avoid 409 conflicts. |
 
 #### Example
 
 ```php
 $result = $loops->emailMessages->update(
-  id: 'cly8k3m0n0044jpx2bghepq45',
+  email_message_id: 'cly8k3m0n0044jpx2bghepq45',
   fields: [
     'expectedRevisionId' => 'clm9n4o6p0088lrz4dijslt67',
     'subject' => 'Updated subject',
@@ -1564,7 +1564,7 @@ Send a test preview of an email message to one or more addresses.
 
 | Name                   | Type     | Required | Notes                                                                             |
 | ---------------------- | -------- | -------- | --------------------------------------------------------------------------------- |
-| `$id`                  | string   | Yes      | The ID of the email message.                                                      |
+| `$email_message_id`    | string   | Yes      | The ID of the email message.                                                      |
 | `$emails`              | array    | Yes      | One or more addresses to send the preview to.                                     |
 | `$contact_properties`  | array    | No       | Contact property values to render. Accepted for campaign and workflow previews.   |
 | `$event_properties`    | array    | No       | Event property values to render. Accepted for workflow previews only.             |
@@ -1574,7 +1574,7 @@ Send a test preview of an email message to one or more addresses.
 
 ```php
 $result = $loops->emailMessages->preview(
-  id: 'cly8k3m0n0044jpx2bghepq45',
+  email_message_id: 'cly8k3m0n0044jpx2bghepq45',
   emails: ['test@example.com'],
   contact_properties: ['firstName' => 'Alex']
 );
@@ -1634,12 +1634,12 @@ Get a transactional group by ID.
 
 | Name  | Type   | Required | Notes                             |
 | ----- | ------ | -------- | --------------------------------- |
-| `$id` | string | Yes      | The ID of the transactional group. |
+| `$transactional_group_id` | string | Yes      | The ID of the transactional group. |
 
 #### Example
 
 ```php
-$result = $loops->transactionalGroups->get(id: 'clv2w3x4y0288xbb0kqrsuv67');
+$result = $loops->transactionalGroups->get(transactional_group_id: 'clv2w3x4y0288xbb0kqrsuv67');
 ```
 
 ---
@@ -1654,7 +1654,7 @@ Update a transactional group's name or description.
 
 | Name            | Type   | Required | Notes                                   |
 | --------------- | ------ | -------- | --------------------------------------- |
-| `$id`           | string | Yes      | The ID of the transactional group.      |
+| `$transactional_group_id` | string | Yes      | The ID of the transactional group.      |
 | `$name`         | string | No       | Cannot be the reserved name "Unsorted". |
 | `$description`  | string | No       |                                         |
 
@@ -1664,7 +1664,7 @@ At least one field must be provided.
 
 ```php
 $result = $loops->transactionalGroups->update(
-  id: 'clv2w3x4y0288xbb0kqrsuv67',
+  transactional_group_id: 'clv2w3x4y0288xbb0kqrsuv67',
   name: 'Updated name'
 );
 ```
diff --git a/src/AudienceSegments.php b/src/AudienceSegments.php
index 443e108..9d60740 100644
--- a/src/AudienceSegments.php
+++ b/src/AudienceSegments.php
@@ -28,8 +28,8 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
         ]);
     }
 
-    public function get(string $id): mixed
+    public function get(string $audience_segment_id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/audience-segments/' . $id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/audience-segments/' . $audience_segment_id);
     }
 }
diff --git a/src/CampaignGroups.php b/src/CampaignGroups.php
index ecb5bce..3fc1d2f 100644
--- a/src/CampaignGroups.php
+++ b/src/CampaignGroups.php
@@ -40,12 +40,12 @@ public function create(string $name, ?string $description = null): mixed
         ]);
     }
 
-    public function get(string $id): mixed
+    public function get(string $campaign_group_id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/campaign-groups/' . $id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/campaign-groups/' . $campaign_group_id);
     }
 
-    public function update(string $id, ?string $name = null, ?string $description = null): mixed
+    public function update(string $campaign_group_id, ?string $name = null, ?string $description = null): mixed
     {
         $payload = [];
         if ($name !== null) {
@@ -55,7 +55,7 @@ public function update(string $id, ?string $name = null, ?string $description =
             $payload['description'] = $description;
         }
 
-        return $this->client->query(method: 'POST', endpoint: 'v1/campaign-groups/' . $id, options: [
+        return $this->client->query(method: 'POST', endpoint: 'v1/campaign-groups/' . $campaign_group_id, options: [
             'json' => $payload
         ]);
     }
diff --git a/src/Campaigns.php b/src/Campaigns.php
index caa1735..720f487 100644
--- a/src/Campaigns.php
+++ b/src/Campaigns.php
@@ -58,13 +58,13 @@ public function create(
         ]);
     }
 
-    public function get(string $id): mixed
+    public function get(string $campaign_id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/campaigns/' . $id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/campaigns/' . $campaign_id);
     }
 
     public function update(
-        string $id,
+        string $campaign_id,
         ?string $name = null,
         ?string $campaign_group_id = null,
         ?string $mailing_list_id = null,
@@ -92,7 +92,7 @@ public function update(
             $payload['scheduling'] = $scheduling;
         }
 
-        return $this->client->query(method: 'POST', endpoint: 'v1/campaigns/' . $id, options: [
+        return $this->client->query(method: 'POST', endpoint: 'v1/campaigns/' . $campaign_id, options: [
             'json' => $payload
         ]);
     }
diff --git a/src/Components.php b/src/Components.php
index 18c368d..9f38afa 100644
--- a/src/Components.php
+++ b/src/Components.php
@@ -28,8 +28,8 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
         ]);
     }
 
-    public function get(string $id): mixed
+    public function get(string $component_id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/components/' . $id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/components/' . $component_id);
     }
 }
diff --git a/src/EmailMessages.php b/src/EmailMessages.php
index 6ebdc01..cbbf82b 100644
--- a/src/EmailMessages.php
+++ b/src/EmailMessages.php
@@ -13,20 +13,20 @@ public function __construct(LoopsClient $client)
         $this->client = $client;
     }
 
-    public function get(string $id): mixed
+    public function get(string $email_message_id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/email-messages/' . $id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/email-messages/' . $email_message_id);
     }
 
-    public function update(string $id, array $fields = []): mixed
+    public function update(string $email_message_id, array $fields = []): mixed
     {
-        return $this->client->query(method: 'POST', endpoint: 'v1/email-messages/' . $id, options: [
+        return $this->client->query(method: 'POST', endpoint: 'v1/email-messages/' . $email_message_id, options: [
             'json' => $fields
         ]);
     }
 
     public function preview(
-        string $id,
+        string $email_message_id,
         array $emails,
         ?array $contact_properties = null,
         ?array $event_properties = null,
@@ -43,7 +43,7 @@ public function preview(
             $payload['dataVariables'] = $data_variables;
         }
 
-        return $this->client->query(method: 'POST', endpoint: 'v1/email-messages/' . $id . '/preview', options: [
+        return $this->client->query(method: 'POST', endpoint: 'v1/email-messages/' . $email_message_id . '/preview', options: [
             'json' => $payload
         ]);
     }
diff --git a/src/Themes.php b/src/Themes.php
index 80c531d..8c7d6e7 100644
--- a/src/Themes.php
+++ b/src/Themes.php
@@ -28,8 +28,8 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
         ]);
     }
 
-    public function get(string $id): mixed
+    public function get(string $theme_id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/themes/' . $id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/themes/' . $theme_id);
     }
 }
diff --git a/src/Transactional.php b/src/Transactional.php
index 7219c00..6e301e0 100644
--- a/src/Transactional.php
+++ b/src/Transactional.php
@@ -14,7 +14,7 @@ public function __construct(LoopsClient $client)
     }
 
     public function send(
-        string $id,
+        string $transactional_id,
         string $email,
         ?bool $add_to_audience = false,
         ?array $data_variables = [],
@@ -22,7 +22,7 @@ public function send(
         ?array $headers = []
     ): mixed {
         $payload = [
-            'transactionalId' => $id,
+            'transactionalId' => $transactional_id,
             'email' => $email,
             'addToAudience' => $add_to_audience,
             'dataVariables' => $data_variables,
@@ -57,25 +57,25 @@ public function create(string $name): mixed
         ]);
     }
 
-    public function get(string $id): mixed
+    public function get(string $transactional_id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/transactional-emails/' . $id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/transactional-emails/' . $transactional_id);
     }
 
-    public function update(string $id, string $name): mixed
+    public function update(string $transactional_id, string $name): mixed
     {
-        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $id, options: [
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id, options: [
             'json' => ['name' => $name]
         ]);
     }
 
-    public function ensureDraft(string $id): mixed
+    public function ensureDraft(string $transactional_id): mixed
     {
-        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $id . '/draft');
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id . '/draft');
     }
 
-    public function publish(string $id): mixed
+    public function publish(string $transactional_id): mixed
     {
-        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $id . '/publish');
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id . '/publish');
     }
 }
\ No newline at end of file
diff --git a/src/TransactionalGroups.php b/src/TransactionalGroups.php
index d5e856f..9a1aec7 100644
--- a/src/TransactionalGroups.php
+++ b/src/TransactionalGroups.php
@@ -40,12 +40,12 @@ public function create(string $name, ?string $description = null): mixed
         ]);
     }
 
-    public function get(string $id): mixed
+    public function get(string $transactional_group_id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/transactional-groups/' . $id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/transactional-groups/' . $transactional_group_id);
     }
 
-    public function update(string $id, ?string $name = null, ?string $description = null): mixed
+    public function update(string $transactional_group_id, ?string $name = null, ?string $description = null): mixed
     {
         $payload = [];
         if ($name !== null) {
@@ -55,7 +55,7 @@ public function update(string $id, ?string $name = null, ?string $description =
             $payload['description'] = $description;
         }
 
-        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-groups/' . $id, options: [
+        return $this->client->query(method: 'POST', endpoint: 'v1/transactional-groups/' . $transactional_group_id, options: [
             'json' => $payload
         ]);
     }
diff --git a/src/Workflows.php b/src/Workflows.php
index e74d570..5337a09 100644
--- a/src/Workflows.php
+++ b/src/Workflows.php
@@ -28,9 +28,9 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
         ]);
     }
 
-    public function get(string $id): mixed
+    public function get(string $workflow_id): mixed
     {
-        return $this->client->query(method: 'GET', endpoint: 'v1/workflows/' . $id);
+        return $this->client->query(method: 'GET', endpoint: 'v1/workflows/' . $workflow_id);
     }
 
     public function getNode(string $workflow_id, string $node_id): mixed
diff --git a/tests/AudienceSegmentsTest.php b/tests/AudienceSegmentsTest.php
index 71c6e01..c417055 100644
--- a/tests/AudienceSegmentsTest.php
+++ b/tests/AudienceSegmentsTest.php
@@ -59,7 +59,7 @@ public function testGetAudienceSegment(): void
         ])
       ));
 
-    $result = $this->client->audienceSegments->get(id: $segmentId);
+    $result = $this->client->audienceSegments->get(audience_segment_id: $segmentId);
 
     $this->assertEquals($segmentId, $result['id']);
   }
diff --git a/tests/CampaignGroupsTest.php b/tests/CampaignGroupsTest.php
index 5048def..8cc6c19 100644
--- a/tests/CampaignGroupsTest.php
+++ b/tests/CampaignGroupsTest.php
@@ -59,7 +59,7 @@ public function testUpdateCampaignGroup(): void
       ));
 
     $result = $this->client->campaignGroups->update(
-      id: $groupId,
+      campaign_group_id: $groupId,
       name: 'Updated name'
     );
 
diff --git a/tests/CampaignsTest.php b/tests/CampaignsTest.php
index 5bf36ea..39ee98d 100644
--- a/tests/CampaignsTest.php
+++ b/tests/CampaignsTest.php
@@ -89,7 +89,7 @@ public function testFindCampaign(): void
         ])
       ));
 
-    $result = $this->client->campaigns->get(id: $campaignId);
+    $result = $this->client->campaigns->get(campaign_id: $campaignId);
 
     $this->assertEquals($campaignId, $result['campaignId']);
   }
@@ -121,7 +121,7 @@ public function testUpdateCampaign(): void
       ));
 
     $result = $this->client->campaigns->update(
-      id: $campaignId,
+      campaign_id: $campaignId,
       name: 'Updated name'
     );
 
diff --git a/tests/ComponentsTest.php b/tests/ComponentsTest.php
index 8077f8a..b5f5ce0 100644
--- a/tests/ComponentsTest.php
+++ b/tests/ComponentsTest.php
@@ -58,7 +58,7 @@ public function testFindComponent(): void
         ])
       ));
 
-    $result = $this->client->components->get(id: $componentId);
+    $result = $this->client->components->get(component_id: $componentId);
 
     $this->assertEquals($componentId, $result['componentId']);
   }
diff --git a/tests/EmailMessagesTest.php b/tests/EmailMessagesTest.php
index e850b2b..4b8e5ed 100644
--- a/tests/EmailMessagesTest.php
+++ b/tests/EmailMessagesTest.php
@@ -43,7 +43,7 @@ public function testFindEmailMessage(): void
         ])
       ));
 
-    $result = $this->client->emailMessages->get(id: $emailMessageId);
+    $result = $this->client->emailMessages->get(email_message_id: $emailMessageId);
 
     $this->assertEquals($emailMessageId, $result['emailMessageId']);
   }
@@ -84,7 +84,7 @@ public function testUpdateEmailMessage(): void
       ));
 
     $result = $this->client->emailMessages->update(
-      id: $emailMessageId,
+      email_message_id: $emailMessageId,
       fields: $fields
     );
 
@@ -115,7 +115,7 @@ public function testPreviewEmailMessage(): void
       ));
 
     $result = $this->client->emailMessages->preview(
-      id: $emailMessageId,
+      email_message_id: $emailMessageId,
       emails: ['test@example.com'],
       contact_properties: ['firstName' => 'Ada']
     );
diff --git a/tests/ThemesTest.php b/tests/ThemesTest.php
index f919dc0..b4995b6 100644
--- a/tests/ThemesTest.php
+++ b/tests/ThemesTest.php
@@ -65,7 +65,7 @@ public function testFindTheme(): void
         ])
       ));
 
-    $result = $this->client->themes->get(id: $themeId);
+    $result = $this->client->themes->get(theme_id: $themeId);
 
     $this->assertEquals($themeId, $result['themeId']);
   }
diff --git a/tests/TransactionalGroupsTest.php b/tests/TransactionalGroupsTest.php
index f2d8b71..a10d403 100644
--- a/tests/TransactionalGroupsTest.php
+++ b/tests/TransactionalGroupsTest.php
@@ -50,7 +50,7 @@ public function testGetTransactionalGroup(): void
         body: json_encode(['id' => $groupId, 'name' => 'Onboarding'])
       ));
 
-    $result = $this->client->transactionalGroups->get(id: $groupId);
+    $result = $this->client->transactionalGroups->get(transactional_group_id: $groupId);
 
     $this->assertEquals($groupId, $result['id']);
   }
diff --git a/tests/TransactionalTest.php b/tests/TransactionalTest.php
index bfd3b41..1c0ded2 100644
--- a/tests/TransactionalTest.php
+++ b/tests/TransactionalTest.php
@@ -29,7 +29,7 @@ protected function setUp(): void
 
   public function testSendTransactional(): void
   {
-    $id = 'test_template_123';
+    $transactional_id = 'test_template_123';
     $email = 'test@example.com';
     $add_to_audience = true;
     $data_variables = ['name' => 'Test User'];
@@ -48,7 +48,7 @@ public function testSendTransactional(): void
       ->method('post')
       ->with(
         'v1/transactional',
-        $this->callback(function ($options) use ($id, $email, $add_to_audience, $data_variables, $attachments, $custom_headers) {
+        $this->callback(function ($options) use ($transactional_id, $email, $add_to_audience, $data_variables, $attachments, $custom_headers) {
           // Verify the request structure
           if (!isset($options['json']) || !isset($options['headers'])) {
             return false;
@@ -68,7 +68,7 @@ public function testSendTransactional(): void
             && isset($payload['attachments']);
 
           // Verify payload values
-          $has_correct_values = $payload['transactionalId'] === $id
+          $has_correct_values = $payload['transactionalId'] === $transactional_id
             && $payload['email'] === $email
             && $payload['addToAudience'] === $add_to_audience
             && $payload['dataVariables'] === $data_variables
@@ -89,7 +89,7 @@ public function testSendTransactional(): void
 
     // Make the API call
     $result = $this->client->transactional->send(
-      id: $id,
+      transactional_id: $transactional_id,
       email: $email,
       add_to_audience: $add_to_audience,
       data_variables: $data_variables,
@@ -231,7 +231,7 @@ public function testGetTransactional(): void
         ])
       ));
 
-    $result = $this->client->transactional->get(id: $transactionalId);
+    $result = $this->client->transactional->get(transactional_id: $transactionalId);
 
     $this->assertEquals($transactionalId, $result['id']);
   }
@@ -263,7 +263,7 @@ public function testUpdateTransactional(): void
       ));
 
     $result = $this->client->transactional->update(
-      id: $transactionalId,
+      transactional_id: $transactionalId,
       name: 'Updated welcome email'
     );
 
@@ -292,7 +292,7 @@ public function testEnsureDraftTransactional(): void
         ])
       ));
 
-    $result = $this->client->transactional->ensureDraft(id: $transactionalId);
+    $result = $this->client->transactional->ensureDraft(transactional_id: $transactionalId);
 
     $this->assertEquals('msg_123', $result['draftEmailMessageId']);
   }
@@ -318,7 +318,7 @@ public function testPublishTransactional(): void
         ])
       ));
 
-    $result = $this->client->transactional->publish(id: $transactionalId);
+    $result = $this->client->transactional->publish(transactional_id: $transactionalId);
 
     $this->assertEquals('msg_123', $result['publishedEmailMessageId']);
   }

From 3ca133c44168ad51a1879b3378a6862dfd63368e Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 24 Jun 2026 14:55:20 +0300
Subject: [PATCH 05/13] Reduce to minor update (no breaking changes)

---
 CHANGELOG.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8b18bce..e801204 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,4 @@
-## v4.0.0 - Jun 24, 2026
+## v3.1.0 - Jun 24, 2026
 
 Added support for new content endpoints:
 

From 75443343af74540eda85a8525d6238418b0e97c2 Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 24 Jun 2026 16:23:05 +0300
Subject: [PATCH 06/13] Add group parameters

---
 README.md                   | 18 +++++++------
 src/Transactional.php       | 29 ++++++++++++++++----
 tests/TransactionalTest.php | 53 +++++++++++++++++++++++++++++++++++++
 3 files changed, 87 insertions(+), 13 deletions(-)

diff --git a/README.md b/README.md
index 893871f..9f4b1ae 100644
--- a/README.md
+++ b/README.md
@@ -943,9 +943,10 @@ Create a new transactional email. An empty draft email message is created automa
 
 #### Parameters
 
-| Name    | Type   | Required | Notes                              |
-| ------- | ------ | -------- | ---------------------------------- |
-| `$name` | string | Yes      | The name of the transactional email. |
+| Name                       | Type   | Required | Notes                                                                                                                        |
+| -------------------------- | ------ | -------- | ---------------------------------------------------------------------------------------------------------------------------- |
+| `$name`                    | string | Yes      | The name of the transactional email.                                                                                         |
+| `$transactional_group_id`  | string | No       | The ID of the group to add this transactional email to. Defaults to the team's default group when omitted.                   |
 
 #### Example
 
@@ -992,16 +993,17 @@ $result = $loops->transactional->get(transactional_id: 'clfq6dinn000yl70fgwwyp82
 
 ### transactional->update()
 
-Update a transactional email's name.
+Update a transactional email.
 
 [API Reference](https://loops.so/docs/api-reference/update-transactional-email)
 
 #### Parameters
 
-| Name                | Type   | Required | Notes                            |
-| ------------------- | ------ | -------- | -------------------------------- |
-| `$transactional_id` | string | Yes      | The ID of the transactional email. |
-| `$name`             | string | Yes      | The updated name.                |
+| Name                       | Type   | Required | Notes                                                                                      |
+| -------------------------- | ------ | -------- | ------------------------------------------------------------------------------------------ |
+| `$transactional_id`          | string | Yes      | The ID of the transactional email.                                                           |
+| `$name`                    | string | No       | The updated name. At least one of `$name` or `$transactional_group_id` must be provided.   |
+| `$transactional_group_id`  | string | No       | The ID of the group to move this transactional email to.                                   |
 
 #### Example
 
diff --git a/src/Transactional.php b/src/Transactional.php
index 6e301e0..61d3b5c 100644
--- a/src/Transactional.php
+++ b/src/Transactional.php
@@ -50,10 +50,15 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
         ]);
     }
 
-    public function create(string $name): mixed
+    public function create(string $name, ?string $transactional_group_id = null): mixed
     {
+        $payload = ['name' => $name];
+        if ($transactional_group_id !== null) {
+            $payload['transactionalGroupId'] = $transactional_group_id;
+        }
+
         return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails', options: [
-            'json' => ['name' => $name]
+            'json' => $payload
         ]);
     }
 
@@ -62,10 +67,24 @@ public function get(string $transactional_id): mixed
         return $this->client->query(method: 'GET', endpoint: 'v1/transactional-emails/' . $transactional_id);
     }
 
-    public function update(string $transactional_id, string $name): mixed
-    {
+    public function update(
+        string $transactional_id,
+        ?string $name = null,
+        ?string $transactional_group_id = null
+    ): mixed {
+        $payload = [];
+        if ($name !== null) {
+            $payload['name'] = $name;
+        }
+        if ($transactional_group_id !== null) {
+            $payload['transactionalGroupId'] = $transactional_group_id;
+        }
+        if ($payload === []) {
+            throw new \InvalidArgumentException(message: 'At least one field must be provided.');
+        }
+
         return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id, options: [
-            'json' => ['name' => $name]
+            'json' => $payload
         ]);
     }
 
diff --git a/tests/TransactionalTest.php b/tests/TransactionalTest.php
index 1c0ded2..3bd488d 100644
--- a/tests/TransactionalTest.php
+++ b/tests/TransactionalTest.php
@@ -210,6 +210,28 @@ public function testCreateTransactional(): void
     $this->assertEquals('msg_123', $result['draftEmailMessageId']);
   }
 
+  public function testCreateTransactionalWithGroup(): void
+  {
+    $groupId = 'grp_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with(
+        'v1/transactional-emails',
+        $this->callback(function ($options) use ($groupId) {
+          return $options['json']['name'] === 'Welcome email'
+            && $options['json']['transactionalGroupId'] === $groupId;
+        })
+      )
+      ->willReturn(new Response(status: 201, body: json_encode(['id' => 'txn_123'])));
+
+    $this->client->transactional->create(
+      name: 'Welcome email',
+      transactional_group_id: $groupId
+    );
+  }
+
   public function testGetTransactional(): void
   {
     $transactionalId = 'txn_123';
@@ -270,6 +292,37 @@ public function testUpdateTransactional(): void
     $this->assertEquals('Updated welcome email', $result['name']);
   }
 
+  public function testUpdateTransactionalGroup(): void
+  {
+    $transactionalId = 'txn_123';
+    $groupId = 'grp_456';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with(
+        'v1/transactional-emails/' . $transactionalId,
+        $this->callback(function ($options) use ($groupId) {
+          return $options['json']['transactionalGroupId'] === $groupId
+            && !isset($options['json']['name']);
+        })
+      )
+      ->willReturn(new Response(status: 200, body: json_encode(['id' => $transactionalId])));
+
+    $this->client->transactional->update(
+      transactional_id: $transactionalId,
+      transactional_group_id: $groupId
+    );
+  }
+
+  public function testUpdateTransactionalWithoutFieldsThrows(): void
+  {
+    $this->expectException(\InvalidArgumentException::class);
+    $this->expectExceptionMessage('At least one field must be provided.');
+
+    $this->client->transactional->update(transactional_id: 'txn_123');
+  }
+
   public function testEnsureDraftTransactional(): void
   {
     $transactionalId = 'txn_123';

From 5e4259aa660c0811b1d5282cfc5e9efd6ca2a846 Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 24 Jun 2026 16:23:27 +0300
Subject: [PATCH 07/13] Fix content_type docs

---
 README.md             | 4 ++--
 src/Transactional.php | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index 9f4b1ae..ba6399d 100644
--- a/README.md
+++ b/README.md
@@ -782,7 +782,7 @@ Send a transactional email to a contact. [Learn about sending transactional emai
 | `$data_variables`                | array   | No       | An array containing data as defined by the data variables added to the transactional email template.<br />Values can be of type `string` or `number`.                                            |
 | `$attachments`                   | array[] | No       | A list of attachments objects.<br />**Please note**: Attachments need to be enabled on your account before using them with the API. [Read more](https://loops.so/docs/transactional/attachments) |
 | `$attachments[]["filename"]`     | string  | No       | The name of the file, shown in email clients.                                                                                                                                                    |
-| `$attachments[]["content_type"]` | string  | No       | The MIME type of the file.                                                                                                                                                                       |
+| `$attachments[]["contentType"]` | string  | No       | The MIME type of the file.                                                                                                                                                                       |
 | `$attachments[]["data"]`         | string  | No       | The base64-encoded content of the file.                                                                                                                                                          |
 | `$headers`                       | array   | No       | Additional headers to send with the request.                                                                                                                                                     |
 
@@ -819,7 +819,7 @@ $result = $loops->transactional->send(
   attachments: [
     [
       'filename' => 'presentation.pdf',
-      'content_type' => 'application/pdf',
+      'contentType' => 'application/pdf',
       'data' => base64_encode(file_get_contents('path/to/presentation.pdf'))
     ]
   ]
diff --git a/src/Transactional.php b/src/Transactional.php
index 61d3b5c..37a75ab 100644
--- a/src/Transactional.php
+++ b/src/Transactional.php
@@ -18,7 +18,7 @@ public function send(
         string $email,
         ?bool $add_to_audience = false,
         ?array $data_variables = [],
-        ?array $attachments = [], /** @var array<array{filename: string, content_type: string, data: string}> */
+        ?array $attachments = [], /** @var array<array{filename: string, contentType: string, data: string}> */
         ?array $headers = []
     ): mixed {
         $payload = [

From e3db9b745819a8a35e1ed49a0b1f1fdf782210b2 Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 24 Jun 2026 16:43:25 +0300
Subject: [PATCH 08/13] Reusable function for payload creation

---
 README.md                   | 10 ++++-----
 src/AudienceSegments.php    | 13 ++++-------
 src/CampaignGroups.php      | 13 ++++-------
 src/Campaigns.php           | 16 ++++++-------
 src/Components.php          | 13 ++++-------
 src/ContactProperties.php   |  8 +++----
 src/Contacts.php            | 45 ++++++++++++++-----------------------
 src/Themes.php              | 13 ++++-------
 src/Transactional.php       | 15 +++++--------
 src/TransactionalGroups.php | 13 ++++-------
 src/Util.php                | 18 +++++++++++++++
 src/Workflows.php           | 13 ++++-------
 tests/UtilTest.php          | 39 ++++++++++++++++++++++++++++++++
 13 files changed, 118 insertions(+), 111 deletions(-)
 create mode 100644 src/Util.php
 create mode 100644 tests/UtilTest.php

diff --git a/README.md b/README.md
index ba6399d..f966f64 100644
--- a/README.md
+++ b/README.md
@@ -1270,9 +1270,9 @@ Get a single campaign by ID.
 
 #### Parameters
 
-| Name                    | Type   | Required | Notes                 |
-| ----------------------- | ------ | -------- | --------------------- |
-| `$campaign_id`                 | string | Yes      | The ID of the campaign. |
+| Name           | Type   | Required | Notes                   |
+| -------------- | ------ | -------- | ----------------------- |
+| `$campaign_id` | string | Yes      | The ID of the campaign. |
 
 #### Example
 
@@ -1292,7 +1292,7 @@ Update a draft campaign's name, group, audience, or scheduling.
 
 | Name                    | Type   | Required | Notes                                                                                                 |
 | ----------------------- | ------ | -------- | ----------------------------------------------------------------------------------------------------- |
-| `$campaign_id`                 | string | Yes      | The ID of the campaign.                                                                               |
+| `$campaign_id`          | string | Yes      | The ID of the campaign.                                                                               |
 | `$name`                 | string | No       | The updated name.                                                                                     |
 | `$campaign_group_id`    | string | No       | The ID of the group to move this campaign to.                                                         |
 | `$mailing_list_id`      | string | No       | The ID of the mailing list to send to.                                                                |
@@ -1539,7 +1539,7 @@ Update an email message's subject, preview text, sender, or LMX content.
 | Name      | Type  | Required | Notes                                                                                                                                                                                                 |
 | --------- | ----- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | `$email_message_id` | string | Yes   | The ID of the email message.                                                                                                                                                                          |
-| `$fields` | array | No       | Fields to update. Use API field names: `expectedRevisionId`, `subject`, `previewText`, `fromName`, `fromEmail`, `replyToEmail`, `lmx`. Supply `expectedRevisionId` matching the current `contentRevisionId` to avoid 409 conflicts. |
+| `$fields` | array | No       | Fields to update. Use API field names: `expectedRevisionId`, `subject`, `previewText`, `fromName`, `fromEmail`, `replyToEmail`, `lmx`, `contactPropertiesFallbacks`, `eventPropertiesFallbacks`, `dataVariablesFallbacks`. Supply `expectedRevisionId` matching the current `contentRevisionId` to avoid 409 conflicts. For the `*Fallbacks` maps, a `null` value deletes an individual fallback entry. |
 
 #### Example
 
diff --git a/src/AudienceSegments.php b/src/AudienceSegments.php
index 9d60740..98afa9d 100644
--- a/src/AudienceSegments.php
+++ b/src/AudienceSegments.php
@@ -15,16 +15,11 @@ public function __construct(LoopsClient $client)
 
     public function list(?int $per_page = null, ?string $cursor = null): mixed
     {
-        $query = [];
-        if ($per_page !== null) {
-            $query['perPage'] = $per_page;
-        }
-        if ($cursor) {
-            $query['cursor'] = $cursor;
-        }
-
         return $this->client->query(method: 'GET', endpoint: 'v1/audience-segments', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'perPage' => $per_page,
+                'cursor' => $cursor,
+            ])
         ]);
     }
 
diff --git a/src/CampaignGroups.php b/src/CampaignGroups.php
index 3fc1d2f..02fd83a 100644
--- a/src/CampaignGroups.php
+++ b/src/CampaignGroups.php
@@ -15,16 +15,11 @@ public function __construct(LoopsClient $client)
 
     public function list(?int $per_page = null, ?string $cursor = null): mixed
     {
-        $query = [];
-        if ($per_page !== null) {
-            $query['perPage'] = $per_page;
-        }
-        if ($cursor) {
-            $query['cursor'] = $cursor;
-        }
-
         return $this->client->query(method: 'GET', endpoint: 'v1/campaign-groups', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'perPage' => $per_page,
+                'cursor' => $cursor,
+            ])
         ]);
     }
 
diff --git a/src/Campaigns.php b/src/Campaigns.php
index 720f487..eeb6755 100644
--- a/src/Campaigns.php
+++ b/src/Campaigns.php
@@ -15,16 +15,11 @@ public function __construct(LoopsClient $client)
 
     public function list(?int $per_page = null, ?string $cursor = null): mixed
     {
-        $query = [];
-        if ($per_page !== null) {
-            $query['perPage'] = $per_page;
-        }
-        if ($cursor) {
-            $query['cursor'] = $cursor;
-        }
-
         return $this->client->query(method: 'GET', endpoint: 'v1/campaigns', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'perPage' => $per_page,
+                'cursor' => $cursor,
+            ])
         ]);
     }
 
@@ -91,6 +86,9 @@ public function update(
         if ($scheduling !== null) {
             $payload['scheduling'] = $scheduling;
         }
+        if ($payload === []) {
+            throw new \InvalidArgumentException(message: 'At least one field must be provided.');
+        }
 
         return $this->client->query(method: 'POST', endpoint: 'v1/campaigns/' . $campaign_id, options: [
             'json' => $payload
diff --git a/src/Components.php b/src/Components.php
index 9f38afa..c1af4b6 100644
--- a/src/Components.php
+++ b/src/Components.php
@@ -15,16 +15,11 @@ public function __construct(LoopsClient $client)
 
     public function list(?int $per_page = null, ?string $cursor = null): mixed
     {
-        $query = [];
-        if ($per_page !== null) {
-            $query['perPage'] = $per_page;
-        }
-        if ($cursor) {
-            $query['cursor'] = $cursor;
-        }
-
         return $this->client->query(method: 'GET', endpoint: 'v1/components', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'perPage' => $per_page,
+                'cursor' => $cursor,
+            ])
         ]);
     }
 
diff --git a/src/ContactProperties.php b/src/ContactProperties.php
index eb45062..9e2ca35 100644
--- a/src/ContactProperties.php
+++ b/src/ContactProperties.php
@@ -26,12 +26,10 @@ public function create(string $name, string $type = 'string' | 'number' | 'boole
     }
     public function list(?string $list = null): mixed
     {
-        $query = [];
-        if ($list) {
-            $query['list'] = $list;
-        }
         return $this->client->query(method: 'GET', endpoint: 'v1/contacts/properties', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'list' => $list,
+            ])
         ]);
     }
 }
\ No newline at end of file
diff --git a/src/Contacts.php b/src/Contacts.php
index ee04dff..9df3971 100644
--- a/src/Contacts.php
+++ b/src/Contacts.php
@@ -51,14 +51,12 @@ public function find(?string $email = null, ?string $user_id = null): mixed
         if (!$email && !$user_id) {
             throw new \InvalidArgumentException(message: 'You must provide an email or user_id value.');
         }
-        $query = [];
-        if ($email)
-            $query['email'] = $email;
-        if ($user_id)
-            $query['userId'] = $user_id;
 
         return $this->client->query(method: 'GET', endpoint: 'v1/contacts/find', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'email' => $email,
+                'userId' => $user_id,
+            ])
         ]);
     }
 
@@ -71,14 +69,11 @@ public function delete(?string $email = null, ?string $user_id = null): mixed
             throw new \InvalidArgumentException(message: 'You must provide an email or user_id value.');
         }
 
-        $payload = [];
-        if ($email)
-            $payload['email'] = $email;
-        if ($user_id)
-            $payload['userId'] = $user_id;
-
         return $this->client->query(method: 'POST', endpoint: 'v1/contacts/delete', options: [
-            'json' => $payload
+            'json' => Util::omitNull([
+                'email' => $email,
+                'userId' => $user_id,
+            ])
         ]);
     }
 
@@ -91,14 +86,11 @@ public function checkSuppression(?string $email = null, ?string $user_id = null)
             throw new \InvalidArgumentException(message: 'You must provide an email or user_id value.');
         }
 
-        $query = [];
-        if ($email)
-            $query['email'] = $email;
-        if ($user_id)
-            $query['userId'] = $user_id;
-
         return $this->client->query(method: 'GET', endpoint: 'v1/contacts/suppression', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'email' => $email,
+                'userId' => $user_id,
+            ])
         ]);
     }
 
@@ -111,14 +103,11 @@ public function removeSuppression(?string $email = null, ?string $user_id = null
             throw new \InvalidArgumentException(message: 'You must provide an email or user_id value.');
         }
 
-        $query = [];
-        if ($email)
-            $query['email'] = $email;
-        if ($user_id)
-            $query['userId'] = $user_id;
-
         return $this->client->query(method: 'DELETE', endpoint: 'v1/contacts/suppression', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'email' => $email,
+                'userId' => $user_id,
+            ])
         ]);
     }
-}
\ No newline at end of file
+}
diff --git a/src/Themes.php b/src/Themes.php
index 8c7d6e7..ad0ba2b 100644
--- a/src/Themes.php
+++ b/src/Themes.php
@@ -15,16 +15,11 @@ public function __construct(LoopsClient $client)
 
     public function list(?int $per_page = null, ?string $cursor = null): mixed
     {
-        $query = [];
-        if ($per_page !== null) {
-            $query['perPage'] = $per_page;
-        }
-        if ($cursor) {
-            $query['cursor'] = $cursor;
-        }
-
         return $this->client->query(method: 'GET', endpoint: 'v1/themes', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'perPage' => $per_page,
+                'cursor' => $cursor,
+            ])
         ]);
     }
 
diff --git a/src/Transactional.php b/src/Transactional.php
index 37a75ab..3df84a1 100644
--- a/src/Transactional.php
+++ b/src/Transactional.php
@@ -37,16 +37,11 @@ public function send(
 
     public function list(?int $per_page = null, ?string $cursor = null): mixed
     {
-        $query = [];
-        if ($per_page !== null) {
-            $query['perPage'] = $per_page;
-        }
-        if ($cursor) {
-            $query['cursor'] = $cursor;
-        }
-
         return $this->client->query(method: 'GET', endpoint: 'v1/transactional-emails', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'perPage' => $per_page,
+                'cursor' => $cursor,
+            ])
         ]);
     }
 
@@ -97,4 +92,4 @@ public function publish(string $transactional_id): mixed
     {
         return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails/' . $transactional_id . '/publish');
     }
-}
\ No newline at end of file
+}
diff --git a/src/TransactionalGroups.php b/src/TransactionalGroups.php
index 9a1aec7..ca7eb39 100644
--- a/src/TransactionalGroups.php
+++ b/src/TransactionalGroups.php
@@ -15,16 +15,11 @@ public function __construct(LoopsClient $client)
 
     public function list(?int $per_page = null, ?string $cursor = null): mixed
     {
-        $query = [];
-        if ($per_page !== null) {
-            $query['perPage'] = $per_page;
-        }
-        if ($cursor) {
-            $query['cursor'] = $cursor;
-        }
-
         return $this->client->query(method: 'GET', endpoint: 'v1/transactional-groups', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'perPage' => $per_page,
+                'cursor' => $cursor,
+            ])
         ]);
     }
 
diff --git a/src/Util.php b/src/Util.php
new file mode 100644
index 0000000..b22106d
--- /dev/null
+++ b/src/Util.php
@@ -0,0 +1,18 @@
+<?php
+
+namespace Loops;
+
+final class Util
+{
+    /**
+     * Returns a copy of the array with null values removed.
+     * Use for query parameters where null means "not provided".
+     *
+     * @param array<string, mixed> $params
+     * @return array<string, mixed>
+     */
+    public static function omitNull(array $params): array
+    {
+        return array_filter($params, fn ($value) => $value !== null);
+    }
+}
diff --git a/src/Workflows.php b/src/Workflows.php
index 5337a09..6a9abf6 100644
--- a/src/Workflows.php
+++ b/src/Workflows.php
@@ -15,16 +15,11 @@ public function __construct(LoopsClient $client)
 
     public function list(?int $per_page = null, ?string $cursor = null): mixed
     {
-        $query = [];
-        if ($per_page !== null) {
-            $query['perPage'] = $per_page;
-        }
-        if ($cursor) {
-            $query['cursor'] = $cursor;
-        }
-
         return $this->client->query(method: 'GET', endpoint: 'v1/workflows', options: [
-            'query' => $query
+            'query' => Util::omitNull([
+                'perPage' => $per_page,
+                'cursor' => $cursor,
+            ])
         ]);
     }
 
diff --git a/tests/UtilTest.php b/tests/UtilTest.php
new file mode 100644
index 0000000..618964c
--- /dev/null
+++ b/tests/UtilTest.php
@@ -0,0 +1,39 @@
+<?php
+
+namespace Tests;
+
+use Loops\Util;
+use PHPUnit\Framework\TestCase;
+
+class UtilTest extends TestCase
+{
+  public function testOmitNullRemovesNullValues(): void
+  {
+    $result = Util::omitNull([
+      'name' => 'Test',
+      'campaignGroupId' => null,
+      'mailingListId' => 'list_123',
+      'audienceSegmentId' => null,
+    ]);
+
+    $this->assertEquals([
+      'name' => 'Test',
+      'mailingListId' => 'list_123',
+    ], $result);
+  }
+
+  public function testOmitNullKeepsFalsyNonNullValues(): void
+  {
+    $result = Util::omitNull([
+      'addToAudience' => false,
+      'dataVariables' => [],
+      'count' => 0,
+    ]);
+
+    $this->assertEquals([
+      'addToAudience' => false,
+      'dataVariables' => [],
+      'count' => 0,
+    ], $result);
+  }
+}

From ff03b98742fccf6cbeb4d9bacac540b893d10a1a Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 24 Jun 2026 16:43:36 +0300
Subject: [PATCH 09/13] Better handling of null email/userId

---
 src/Contacts.php | 15 ++++++++++-----
 src/Events.php   | 23 ++++++++++++++---------
 2 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/src/Contacts.php b/src/Contacts.php
index 9df3971..0113974 100644
--- a/src/Contacts.php
+++ b/src/Contacts.php
@@ -31,11 +31,16 @@ public function update(?string $email = null, ?string $user_id = null, ?array $p
         if (!$email && !$user_id) {
             throw new \InvalidArgumentException(message: 'You must provide an email or user_id value.');
         }
-        $payload = [
-            'email' => $email,
-            'userId' => $user_id,
-            'mailingLists' => $mailing_lists
-        ];
+        $payload = [];
+        if ($email !== null) {
+            $payload['email'] = $email;
+        }
+        if ($user_id !== null) {
+            $payload['userId'] = $user_id;
+        }
+        if ($mailing_lists !== []) {
+            $payload['mailingLists'] = $mailing_lists;
+        }
         $payload = array_merge($payload, $properties);
 
         return $this->client->query(method: 'PUT', endpoint: 'v1/contacts/update', options: [
diff --git a/src/Events.php b/src/Events.php
index df99b2a..2a18000 100644
--- a/src/Events.php
+++ b/src/Events.php
@@ -25,14 +25,19 @@ public function send(
             throw new \InvalidArgumentException(message: 'You must provide an email or user_id value.');
         }
 
-        $payload = [
-            'eventName' => $event_name,
-            'email' => $email,
-            'userId' => $user_id,
-            'eventProperties' => $event_properties,
-            'mailingLists' => $mailing_lists,
-        ];
-
+        $payload = ['eventName' => $event_name];
+        if ($email !== null) {
+            $payload['email'] = $email;
+        }
+        if ($user_id !== null) {
+            $payload['userId'] = $user_id;
+        }
+        if ($event_properties !== []) {
+            $payload['eventProperties'] = $event_properties;
+        }
+        if ($mailing_lists !== []) {
+            $payload['mailingLists'] = $mailing_lists;
+        }
         $payload = array_merge($payload, $contact_properties);
 
         return $this->client->query(method: 'POST', endpoint: 'v1/events/send', options: [
@@ -40,4 +45,4 @@ public function send(
             'headers' => $headers
         ]);
     }
-}
\ No newline at end of file
+}

From 45b072ea313d8a4d2dc4a711150bce1c6468fa87 Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 24 Jun 2026 17:27:38 +0300
Subject: [PATCH 10/13] Use different Guzzle client for S3 uploads

---
 src/LoopsClient.php   | 21 +++++++++++++++++++++
 src/Uploads.php       |  2 +-
 tests/UploadsTest.php |  8 ++++++--
 3 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/src/LoopsClient.php b/src/LoopsClient.php
index eac1d64..b86fd18 100644
--- a/src/LoopsClient.php
+++ b/src/LoopsClient.php
@@ -7,6 +7,7 @@ class LoopsClient
   private const BASE_URI = 'https://app.loops.so/api/';
 
   private \GuzzleHttp\Client $httpClient;
+  private \GuzzleHttp\Client $uploadHttpClient;
   public ApiKey $apiKey;
   public Contacts $contacts;
   public Events $events;
@@ -35,6 +36,10 @@ public function __construct(string $api_key)
       'http_errors' => false
     ]);
 
+    $this->uploadHttpClient = new \GuzzleHttp\Client(config: [
+      'http_errors' => false,
+    ]);
+
     $this->apiKey = new ApiKey(client: $this);
     $this->contacts = new Contacts(client: $this);
     $this->events = new Events(client: $this);
@@ -69,6 +74,22 @@ public function getHttpClient(): \GuzzleHttp\Client
     return $this->httpClient;
   }
 
+  /**
+   * Sets the HTTP client used for pre-signed upload URLs. Primarily for testing.
+   *
+   * @param \GuzzleHttp\Client $client
+   * @return void
+   */
+  public function setUploadHttpClient(\GuzzleHttp\Client $client): void
+  {
+    $this->uploadHttpClient = $client;
+  }
+
+  public function getUploadHttpClient(): \GuzzleHttp\Client
+  {
+    return $this->uploadHttpClient;
+  }
+
   /**
    * Performs an HTTP request to the Loops API
    *
diff --git a/src/Uploads.php b/src/Uploads.php
index ad2723f..45c4551 100644
--- a/src/Uploads.php
+++ b/src/Uploads.php
@@ -59,7 +59,7 @@ public function upload(string $path): mixed
             ]
         ]);
 
-        $response = $this->client->getHttpClient()->put($created['presignedUrl'], [
+        $response = $this->client->getUploadHttpClient()->put($created['presignedUrl'], [
             'headers' => [
                 'Content-Type' => $content_type,
                 'Content-Length' => (string) $content_length,
diff --git a/tests/UploadsTest.php b/tests/UploadsTest.php
index fdbeb2e..e2bd52a 100644
--- a/tests/UploadsTest.php
+++ b/tests/UploadsTest.php
@@ -10,13 +10,16 @@ class UploadsTest extends TestCase
 {
   private LoopsClient $client;
   private \GuzzleHttp\Client $mockHttpClient;
+  private \GuzzleHttp\Client $mockUploadHttpClient;
   private string $imagePath;
 
   protected function setUp(): void
   {
     $this->mockHttpClient = $this->createMock(\GuzzleHttp\Client::class);
+    $this->mockUploadHttpClient = $this->createMock(\GuzzleHttp\Client::class);
     $this->client = new LoopsClient('test_api_key');
     $this->client->setHttpClient($this->mockHttpClient);
+    $this->client->setUploadHttpClient($this->mockUploadHttpClient);
 
     $this->imagePath = sys_get_temp_dir() . '/loops_upload_test.png';
     file_put_contents(
@@ -69,13 +72,14 @@ public function testUpload(): void
         $this->fail('Unexpected POST endpoint: ' . $endpoint);
       });
 
-    $this->mockHttpClient
+    $this->mockUploadHttpClient
       ->expects($this->once())
       ->method('put')
       ->with(
         $presignedUrl,
         $this->callback(function ($options) use ($fileContents, $contentLength) {
-          return $options['headers']['Content-Type'] === 'image/png'
+          return !isset($options['headers']['Authorization'])
+            && $options['headers']['Content-Type'] === 'image/png'
             && $options['headers']['Content-Length'] === (string) $contentLength
             && $options['body'] === $fileContents;
         })

From 96df06a163cfc2ec4bbace58e0c27d352e3c856e Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Wed, 24 Jun 2026 17:37:28 +0300
Subject: [PATCH 11/13] Use omitNull in more places

---
 src/CampaignGroups.php      | 21 ++++++++++-----------
 src/Contacts.php            | 29 +++++++++++++----------------
 src/Events.php              | 23 +++++++++--------------
 src/Transactional.php       | 21 ++++++++-------------
 src/TransactionalGroups.php | 22 ++++++++++------------
 5 files changed, 50 insertions(+), 66 deletions(-)

diff --git a/src/CampaignGroups.php b/src/CampaignGroups.php
index 02fd83a..d6f4766 100644
--- a/src/CampaignGroups.php
+++ b/src/CampaignGroups.php
@@ -25,13 +25,12 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
 
     public function create(string $name, ?string $description = null): mixed
     {
-        $payload = ['name' => $name];
-        if ($description !== null) {
-            $payload['description'] = $description;
-        }
 
         return $this->client->query(method: 'POST', endpoint: 'v1/campaign-groups', options: [
-            'json' => $payload
+            'json' => Util::omitNull([
+                'name' => $name,
+                'description' => $description,
+            ])
         ]);
     }
 
@@ -42,12 +41,12 @@ public function get(string $campaign_group_id): mixed
 
     public function update(string $campaign_group_id, ?string $name = null, ?string $description = null): mixed
     {
-        $payload = [];
-        if ($name !== null) {
-            $payload['name'] = $name;
-        }
-        if ($description !== null) {
-            $payload['description'] = $description;
+        $payload = Util::omitNull([
+            'name' => $name,
+            'description' => $description,
+        ]);
+        if ($payload === []) {
+            throw new \InvalidArgumentException(message: 'At least one field must be provided.');
         }
 
         return $this->client->query(method: 'POST', endpoint: 'v1/campaign-groups/' . $campaign_group_id, options: [
diff --git a/src/Contacts.php b/src/Contacts.php
index 0113974..b7e37b1 100644
--- a/src/Contacts.php
+++ b/src/Contacts.php
@@ -15,11 +15,13 @@ public function __construct(LoopsClient $client)
 
     public function create(string $email, ?array $properties = [], ?array $mailing_lists = []): mixed
     {
-        $payload = [
-            'email' => $email,
-            'mailingLists' => $mailing_lists
-        ];
-        $payload = array_merge($payload, $properties);
+        $payload = array_merge(
+            [
+                'email' => $email,
+                'mailingLists' => $mailing_lists
+            ], 
+            $properties
+        );
 
         return $this->client->query(method: 'POST', endpoint: 'v1/contacts/create', options: [
             'json' => $payload
@@ -31,17 +33,12 @@ public function update(?string $email = null, ?string $user_id = null, ?array $p
         if (!$email && !$user_id) {
             throw new \InvalidArgumentException(message: 'You must provide an email or user_id value.');
         }
-        $payload = [];
-        if ($email !== null) {
-            $payload['email'] = $email;
-        }
-        if ($user_id !== null) {
-            $payload['userId'] = $user_id;
-        }
-        if ($mailing_lists !== []) {
-            $payload['mailingLists'] = $mailing_lists;
-        }
-        $payload = array_merge($payload, $properties);
+
+        $payload = array_merge(
+            Util::omitNull(['email' => $email, 'userId' => $user_id]),
+            ['mailingLists' => $mailing_lists],
+            $properties
+        );
 
         return $this->client->query(method: 'PUT', endpoint: 'v1/contacts/update', options: [
             'json' => $payload
diff --git a/src/Events.php b/src/Events.php
index 2a18000..be757e8 100644
--- a/src/Events.php
+++ b/src/Events.php
@@ -25,20 +25,15 @@ public function send(
             throw new \InvalidArgumentException(message: 'You must provide an email or user_id value.');
         }
 
-        $payload = ['eventName' => $event_name];
-        if ($email !== null) {
-            $payload['email'] = $email;
-        }
-        if ($user_id !== null) {
-            $payload['userId'] = $user_id;
-        }
-        if ($event_properties !== []) {
-            $payload['eventProperties'] = $event_properties;
-        }
-        if ($mailing_lists !== []) {
-            $payload['mailingLists'] = $mailing_lists;
-        }
-        $payload = array_merge($payload, $contact_properties);
+        $payload = array_merge(
+            [
+                'eventName' => $event_name,
+                'eventProperties' => $event_properties,
+                'mailingLists' => $mailing_lists,
+            ],
+            Util::omitNull(['email' => $email, 'userId' => $user_id]),
+            $contact_properties
+        );
 
         return $this->client->query(method: 'POST', endpoint: 'v1/events/send', options: [
             'json' => $payload,
diff --git a/src/Transactional.php b/src/Transactional.php
index 3df84a1..800f08d 100644
--- a/src/Transactional.php
+++ b/src/Transactional.php
@@ -47,13 +47,11 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
 
     public function create(string $name, ?string $transactional_group_id = null): mixed
     {
-        $payload = ['name' => $name];
-        if ($transactional_group_id !== null) {
-            $payload['transactionalGroupId'] = $transactional_group_id;
-        }
-
         return $this->client->query(method: 'POST', endpoint: 'v1/transactional-emails', options: [
-            'json' => $payload
+            'json' => Util::omitNull([
+                'name' => $name,
+                'transactionalGroupId' => $transactional_group_id,
+            ])
         ]);
     }
 
@@ -67,13 +65,10 @@ public function update(
         ?string $name = null,
         ?string $transactional_group_id = null
     ): mixed {
-        $payload = [];
-        if ($name !== null) {
-            $payload['name'] = $name;
-        }
-        if ($transactional_group_id !== null) {
-            $payload['transactionalGroupId'] = $transactional_group_id;
-        }
+        $payload = Util::omitNull([
+            'name' => $name,
+            'transactionalGroupId' => $transactional_group_id,
+        ]);
         if ($payload === []) {
             throw new \InvalidArgumentException(message: 'At least one field must be provided.');
         }
diff --git a/src/TransactionalGroups.php b/src/TransactionalGroups.php
index ca7eb39..ba8e32e 100644
--- a/src/TransactionalGroups.php
+++ b/src/TransactionalGroups.php
@@ -25,13 +25,11 @@ public function list(?int $per_page = null, ?string $cursor = null): mixed
 
     public function create(string $name, ?string $description = null): mixed
     {
-        $payload = ['name' => $name];
-        if ($description !== null) {
-            $payload['description'] = $description;
-        }
-
         return $this->client->query(method: 'POST', endpoint: 'v1/transactional-groups', options: [
-            'json' => $payload
+            'json' => Util::omitNull([
+                'name' => $name,
+                'description' => $description,
+            ])
         ]);
     }
 
@@ -42,12 +40,12 @@ public function get(string $transactional_group_id): mixed
 
     public function update(string $transactional_group_id, ?string $name = null, ?string $description = null): mixed
     {
-        $payload = [];
-        if ($name !== null) {
-            $payload['name'] = $name;
-        }
-        if ($description !== null) {
-            $payload['description'] = $description;
+        $payload = Util::omitNull([
+            'name' => $name,
+            'description' => $description,
+        ]);
+        if ($payload === []) {
+            throw new \InvalidArgumentException(message: 'At least one field must be provided.');
         }
 
         return $this->client->query(method: 'POST', endpoint: 'v1/transactional-groups/' . $transactional_group_id, options: [

From 2810ce41b1e63d40037ad490fe796c7a5bcfaf7e Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Fri, 26 Jun 2026 16:04:49 +0300
Subject: [PATCH 12/13] Params for updating EmailMessage; fix null values

---
 .github/workflows/php-tests.yml |  2 +-
 README.md                       | 66 +++++++++++++++++++++-------
 composer.json                   |  2 +-
 src/Campaigns.php               | 68 +++++++++++------------------
 src/Core.php                    |  8 ++++
 src/EmailMessages.php           | 51 ++++++++++++++++------
 src/Events.php                  |  5 ++-
 src/Omit.php                    |  8 ++++
 src/Util.php                    | 34 ++++++++++-----
 tests/CampaignsTest.php         | 76 +++++++++++++++++++++++++++++++++
 tests/EmailMessagesTest.php     | 20 +++++----
 tests/UtilTest.php              | 22 ++++++++++
 12 files changed, 268 insertions(+), 94 deletions(-)
 create mode 100644 src/Core.php
 create mode 100644 src/Omit.php

diff --git a/.github/workflows/php-tests.yml b/.github/workflows/php-tests.yml
index 5325b3b..db07f91 100644
--- a/.github/workflows/php-tests.yml
+++ b/.github/workflows/php-tests.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        php-version: ["8.2", "8.3", "8.4"]
+        php-version: ["8.1", "8.2", "8.3", "8.4"]
       fail-fast: false
 
     steps:
diff --git a/README.md b/README.md
index f966f64..5f80839 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,8 @@ Install the Loops package [using Composer](https://packagist.org/packages/loops-
 composer require loops-so/loops
 ```
 
+Requires PHP 8.1.
+
 ## Usage
 
 You will need a Loops API key to use the package.
@@ -995,15 +997,18 @@ $result = $loops->transactional->get(transactional_id: 'clfq6dinn000yl70fgwwyp82
 
 Update a transactional email.
 
+At least one field alongside `transactional_id` must be provided.
+
 [API Reference](https://loops.so/docs/api-reference/update-transactional-email)
 
 #### Parameters
 
+
 | Name                       | Type   | Required | Notes                                                                                      |
 | -------------------------- | ------ | -------- | ------------------------------------------------------------------------------------------ |
-| `$transactional_id`          | string | Yes      | The ID of the transactional email.                                                           |
-| `$name`                    | string | No       | The updated name. At least one of `$name` or `$transactional_group_id` must be provided.   |
-| `$transactional_group_id`  | string | No       | The ID of the group to move this transactional email to.                                   |
+| `$transactional_id`        | string | Yes      | The ID of the transactional email.                                                         |
+| `$name`                    | string | No       | The updated name.   |
+| `$transactional_group_id`  | string | No       | The ID of the group to move this transactional email to.  |
 
 #### Example
 
@@ -1286,6 +1291,8 @@ $result = $loops->campaigns->get(campaign_id: 'cln4o7p9q0110msw5ekjtmv78');
 
 Update a draft campaign's name, group, audience, or scheduling.
 
+At least one field alongside `campaign_id` must be provided.
+
 [API Reference](https://loops.so/docs/api-reference/update-campaign)
 
 #### Parameters
@@ -1295,12 +1302,11 @@ Update a draft campaign's name, group, audience, or scheduling.
 | `$campaign_id`          | string | Yes      | The ID of the campaign.                                                                               |
 | `$name`                 | string | No       | The updated name.                                                                                     |
 | `$campaign_group_id`    | string | No       | The ID of the group to move this campaign to.                                                         |
-| `$mailing_list_id`      | string | No       | The ID of the mailing list to send to.                                                                |
-| `$audience_segment_id`  | string | No       | The ID of an audience segment. Setting this clears any `audience_filter`.                             |
-| `$audience_filter`      | array  | No       | A tree of audience conditions. See the API reference for the filter schema.                           |
 | `$scheduling`           | array  | No       | When the campaign should send. Use `['method' => 'now']` or `['method' => 'schedule', 'timestamp' => '...']`. |
+| `$mailing_list_id`      | string | No       | The ID of the mailing list to send to. Pass `null` to clear.                                          |
+| `$audience_segment_id`  | string | No       | The ID of an audience segment. Setting this clears any `audience_filter`. Pass `null` to clear.       |
+| `$audience_filter`      | array  | No       | A tree of audience conditions. See the API reference for the filter schema. Pass `null` to clear.     |
 
-At least one field must be provided.
 
 #### Example
 
@@ -1309,6 +1315,12 @@ $result = $loops->campaigns->update(
   campaign_id: 'cln4o7p9q0110msw5ekjtmv78',
   name: 'Updated name'
 );
+
+// Clear the mailing list audience target
+$result = $loops->campaigns->update(
+  campaign_id: 'cln4o7p9q0110msw5ekjtmv78',
+  mailing_list_id: null
+);
 ```
 
 ---
@@ -1379,6 +1391,8 @@ $result = $loops->campaignGroups->get(campaign_group_id: 'clq7r0s2t0176pvz8hnmpw
 
 Update a campaign group's name or description.
 
+At least one field alongside `campaign_group_id` must be provided.
+
 [API Reference](https://loops.so/docs/api-reference/update-campaign-group)
 
 #### Parameters
@@ -1389,8 +1403,6 @@ Update a campaign group's name or description.
 | `$name`         | string | No       | Cannot be the reserved name "Unsorted". |
 | `$description`  | string | No       |                                         |
 
-At least one field must be provided.
-
 #### Example
 
 ```php
@@ -1530,7 +1542,9 @@ $result = $loops->emailMessages->get(email_message_id: 'cly8k3m0n0044jpx2bghepq4
 
 ### emailMessages->update()
 
-Update an email message's subject, preview text, sender, or LMX content.
+Update an email message.
+
+At least one field alongside `email_message_id` must be provided.
 
 [API Reference](https://loops.so/docs/api-reference/update-email-message)
 
@@ -1539,19 +1553,38 @@ Update an email message's subject, preview text, sender, or LMX content.
 | Name      | Type  | Required | Notes                                                                                                                                                                                                 |
 | --------- | ----- | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | `$email_message_id` | string | Yes   | The ID of the email message.                                                                                                                                                                          |
-| `$fields` | array | No       | Fields to update. Use API field names: `expectedRevisionId`, `subject`, `previewText`, `fromName`, `fromEmail`, `replyToEmail`, `lmx`, `contactPropertiesFallbacks`, `eventPropertiesFallbacks`, `dataVariablesFallbacks`. Supply `expectedRevisionId` matching the current `contentRevisionId` to avoid 409 conflicts. For the `*Fallbacks` maps, a `null` value deletes an individual fallback entry. |
+| `$expected_revision_id` | string | No | Supply a value matching the current `contentRevisionId` to avoid 409 conflicts. |
+| `$subject` | string | No | The email subject line. |
+| `$preview_text` | string | No | The email preview text. |
+| `$from_name` | string | No | The sender name. |
+| `$from_email` | string | No | The sender email address (the name before the `@`; your sending domain will be automatically appended). |
+| `$reply_to_email` | string | No | The reply-to email address. |
+| `$lmx` | string | No | The LMX content for the email message. |
+| `$contact_properties_fallbacks` | array | No | Contact property fallback values. Pass `null` as a value to remove an individual fallback entry. |
+| `$event_properties_fallbacks` | array | No | Event property fallback values. Pass `null` as a value to remove an individual fallback entry. |
+| `$data_variables_fallbacks` | array | No | Data variable fallback values. Pass `null` as a value to remove an individual fallback entry. |
+
 
 #### Example
 
 ```php
 $result = $loops->emailMessages->update(
   email_message_id: 'cly8k3m0n0044jpx2bghepq45',
-  fields: [
-    'expectedRevisionId' => 'clm9n4o6p0088lrz4dijslt67',
-    'subject' => 'Updated subject',
-    'lmx' => '<Email><Text>Hello</Text></Email>'
+  expected_revision_id: 'clm9n4o6p0088lrz4dijslt67',
+  subject: 'Updated subject',
+  lmx: '<Email><Text>Hello</Text></Email>'
+);
+
+// Example with contact property fallbacks
+$result = $loops->emailMessages->update(
+  email_message_id: 'cly8k3m0n0044jpx2bghepq45',
+  contact_properties_fallbacks: [
+    'firstName' => 'there',      // If firstName is missing, use "there"
+    'company' => 'your company', // If company is missing, use "your company"
+    'planName' => null           // null removes the fallback for "planName"
   ]
 );
+
 ```
 
 ---
@@ -1650,6 +1683,8 @@ $result = $loops->transactionalGroups->get(transactional_group_id: 'clv2w3x4y028
 
 Update a transactional group's name or description.
 
+At least one field alongside `transactional_group_id` must be provided.
+
 [API Reference](https://loops.so/docs/api-reference/update-transactional-group)
 
 #### Parameters
@@ -1660,7 +1695,6 @@ Update a transactional group's name or description.
 | `$name`         | string | No       | Cannot be the reserved name "Unsorted". |
 | `$description`  | string | No       |                                         |
 
-At least one field must be provided.
 
 #### Example
 
diff --git a/composer.json b/composer.json
index 2c3e1d9..5c143e7 100644
--- a/composer.json
+++ b/composer.json
@@ -5,7 +5,7 @@
   "type": "library",
   "homepage": "https://github.com/Loops-so/loops-php",
   "require": {
-    "php": "^8.0",
+    "php": "^8.1",
     "guzzlehttp/guzzle": "^7.9"
   },
   "autoload": {
diff --git a/src/Campaigns.php b/src/Campaigns.php
index eeb6755..f59309e 100644
--- a/src/Campaigns.php
+++ b/src/Campaigns.php
@@ -31,22 +31,16 @@ public function create(
         ?array $audience_filter = null,
         ?array $scheduling = null
     ): mixed {
-        $payload = ['name' => $name];
-        if ($campaign_group_id !== null) {
-            $payload['campaignGroupId'] = $campaign_group_id;
-        }
-        if ($mailing_list_id !== null) {
-            $payload['mailingListId'] = $mailing_list_id;
-        }
-        if ($audience_segment_id !== null) {
-            $payload['audienceSegmentId'] = $audience_segment_id;
-        }
-        if ($audience_filter !== null) {
-            $payload['audienceFilter'] = $audience_filter;
-        }
-        if ($scheduling !== null) {
-            $payload['scheduling'] = $scheduling;
-        }
+        $payload = array_merge(
+            ['name' => $name],
+            Util::omitNull([
+                'campaignGroupId' => $campaign_group_id,
+                'mailingListId' => $mailing_list_id,
+                'audienceSegmentId' => $audience_segment_id,
+                'audienceFilter' => $audience_filter,
+                'scheduling' => $scheduling,
+            ])
+        );
 
         return $this->client->query(method: 'POST', endpoint: 'v1/campaigns', options: [
             'json' => $payload
@@ -60,35 +54,25 @@ public function get(string $campaign_id): mixed
 
     public function update(
         string $campaign_id,
-        ?string $name = null,
+        string $name,
         ?string $campaign_group_id = null,
-        ?string $mailing_list_id = null,
-        ?string $audience_segment_id = null,
-        ?array $audience_filter = null,
+        mixed $mailing_list_id = Core::UNSET,
+        mixed $audience_segment_id = Core::UNSET,
+        mixed $audience_filter = Core::UNSET,
         ?array $scheduling = null
     ): mixed {
-        $payload = [];
-        if ($name !== null) {
-            $payload['name'] = $name;
-        }
-        if ($campaign_group_id !== null) {
-            $payload['campaignGroupId'] = $campaign_group_id;
-        }
-        if ($mailing_list_id !== null) {
-            $payload['mailingListId'] = $mailing_list_id;
-        }
-        if ($audience_segment_id !== null) {
-            $payload['audienceSegmentId'] = $audience_segment_id;
-        }
-        if ($audience_filter !== null) {
-            $payload['audienceFilter'] = $audience_filter;
-        }
-        if ($scheduling !== null) {
-            $payload['scheduling'] = $scheduling;
-        }
-        if ($payload === []) {
-            throw new \InvalidArgumentException(message: 'At least one field must be provided.');
-        }
+        $payload = array_merge(
+            ['name' => $name],
+            Util::omitNull([
+                'campaignGroupId' => $campaign_group_id,
+                'scheduling' => $scheduling,
+            ]),
+            Util::omitUnset([
+                'mailingListId' => $mailing_list_id,
+                'audienceSegmentId' => $audience_segment_id,
+                'audienceFilter' => $audience_filter,
+            ]),
+        );
 
         return $this->client->query(method: 'POST', endpoint: 'v1/campaigns/' . $campaign_id, options: [
             'json' => $payload
diff --git a/src/Core.php b/src/Core.php
new file mode 100644
index 0000000..5086fed
--- /dev/null
+++ b/src/Core.php
@@ -0,0 +1,8 @@
+<?php
+
+namespace Loops;
+
+final class Core
+{
+    public const UNSET = Omit::Unset;
+}
diff --git a/src/EmailMessages.php b/src/EmailMessages.php
index cbbf82b..8daeaa9 100644
--- a/src/EmailMessages.php
+++ b/src/EmailMessages.php
@@ -18,10 +18,37 @@ public function get(string $email_message_id): mixed
         return $this->client->query(method: 'GET', endpoint: 'v1/email-messages/' . $email_message_id);
     }
 
-    public function update(string $email_message_id, array $fields = []): mixed
-    {
+    public function update(
+        string $email_message_id,
+        ?string $expected_revision_id = null,
+        ?string $subject = null,
+        ?string $preview_text = null,
+        ?string $from_name = null,
+        ?string $from_email = null,
+        ?string $reply_to_email = null,
+        ?string $lmx = null,
+        ?array $contact_properties_fallbacks = null,
+        ?array $event_properties_fallbacks = null,
+        ?array $data_variables_fallbacks = null
+    ): mixed {
+        $payload = Util::omitNull([
+            'expectedRevisionId' => $expected_revision_id,
+            'subject' => $subject,
+            'previewText' => $preview_text,
+            'fromName' => $from_name,
+            'fromEmail' => $from_email,
+            'replyToEmail' => $reply_to_email,
+            'lmx' => $lmx,
+            'contactPropertiesFallbacks' => $contact_properties_fallbacks,
+            'eventPropertiesFallbacks' => $event_properties_fallbacks,
+            'dataVariablesFallbacks' => $data_variables_fallbacks,
+        ]);
+        if ($payload === []) {
+            throw new \InvalidArgumentException(message: 'At least one field must be provided.');
+        }
+
         return $this->client->query(method: 'POST', endpoint: 'v1/email-messages/' . $email_message_id, options: [
-            'json' => $fields
+            'json' => $payload
         ]);
     }
 
@@ -32,16 +59,14 @@ public function preview(
         ?array $event_properties = null,
         ?array $data_variables = null
     ): mixed {
-        $payload = ['emails' => $emails];
-        if ($contact_properties !== null) {
-            $payload['contactProperties'] = $contact_properties;
-        }
-        if ($event_properties !== null) {
-            $payload['eventProperties'] = $event_properties;
-        }
-        if ($data_variables !== null) {
-            $payload['dataVariables'] = $data_variables;
-        }
+        $payload = array_merge(
+            ['emails' => $emails],
+            Util::omitNull([
+                'contactProperties' => $contact_properties,
+                'eventProperties' => $event_properties,
+                'dataVariables' => $data_variables,
+            ])
+        );
 
         return $this->client->query(method: 'POST', endpoint: 'v1/email-messages/' . $email_message_id . '/preview', options: [
             'json' => $payload
diff --git a/src/Events.php b/src/Events.php
index be757e8..2dc069b 100644
--- a/src/Events.php
+++ b/src/Events.php
@@ -31,7 +31,10 @@ public function send(
                 'eventProperties' => $event_properties,
                 'mailingLists' => $mailing_lists,
             ],
-            Util::omitNull(['email' => $email, 'userId' => $user_id]),
+            Util::omitNull([
+                'email' => $email,
+                'userId' => $user_id,
+            ]),
             $contact_properties
         );
 
diff --git a/src/Omit.php b/src/Omit.php
new file mode 100644
index 0000000..5d3466d
--- /dev/null
+++ b/src/Omit.php
@@ -0,0 +1,8 @@
+<?php
+
+namespace Loops;
+
+enum Omit
+{
+    case Unset;
+}
diff --git a/src/Util.php b/src/Util.php
index b22106d..d730814 100644
--- a/src/Util.php
+++ b/src/Util.php
@@ -4,15 +4,27 @@
 
 final class Util
 {
-    /**
-     * Returns a copy of the array with null values removed.
-     * Use for query parameters where null means "not provided".
-     *
-     * @param array<string, mixed> $params
-     * @return array<string, mixed>
-     */
-    public static function omitNull(array $params): array
-    {
-        return array_filter($params, fn ($value) => $value !== null);
-    }
+  /**
+   * Returns a copy of the array with null values removed.
+   * Use for query parameters where null means "not provided".
+   *
+   * @param array<string, mixed> $params
+   * @return array<string, mixed>
+   */
+  public static function omitNull(array $params): array
+  {
+    return array_filter($params, fn ($value) => $value !== null);
+  }
+
+  /**
+   * Returns a copy of the array with unset sentinel values removed.
+   * Use for patch parameters where null means "clear" and UNSET means "not provided".
+   *
+   * @param array<string, mixed> $params
+   * @return array<string, mixed>
+   */
+  public static function omitUnset(array $params): array
+  {
+    return array_filter($params, fn ($value) => $value !== Core::UNSET);
+  }
 }
diff --git a/tests/CampaignsTest.php b/tests/CampaignsTest.php
index 39ee98d..b96fdb0 100644
--- a/tests/CampaignsTest.php
+++ b/tests/CampaignsTest.php
@@ -127,4 +127,80 @@ public function testUpdateCampaign(): void
 
     $this->assertEquals('Updated name', $result['name']);
   }
+
+  public function testUpdateCampaignClearsMailingList(): void
+  {
+    $campaignId = 'camp_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with(
+        'v1/campaigns/' . $campaignId,
+        $this->callback(function ($options) {
+          return $options['json'] === [
+            'name' => 'Spring announcement',
+            'mailingListId' => null,
+          ];
+        })
+      )
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'success' => true,
+          'campaignId' => $campaignId,
+          'name' => 'Spring announcement',
+          'status' => 'Draft',
+          'createdAt' => '2025-01-01T00:00:00.000Z',
+          'updatedAt' => '2025-01-02T00:00:00.000Z',
+          'emailMessageId' => 'msg_123'
+        ])
+      ));
+
+    $result = $this->client->campaigns->update(
+      campaign_id: $campaignId,
+      name: 'Spring announcement',
+      mailing_list_id: null
+    );
+
+    $this->assertTrue($result['success']);
+  }
+
+  public function testUpdateCampaignClearsAudienceFilter(): void
+  {
+    $campaignId = 'camp_123';
+
+    $this->mockHttpClient
+      ->expects($this->once())
+      ->method('post')
+      ->with(
+        'v1/campaigns/' . $campaignId,
+        $this->callback(function ($options) {
+          return $options['json'] === [
+            'name' => 'Spring announcement',
+            'audienceFilter' => null,
+          ];
+        })
+      )
+      ->willReturn(new Response(
+        status: 200,
+        body: json_encode([
+          'success' => true,
+          'campaignId' => $campaignId,
+          'name' => 'Spring announcement',
+          'status' => 'Draft',
+          'createdAt' => '2025-01-01T00:00:00.000Z',
+          'updatedAt' => '2025-01-02T00:00:00.000Z',
+          'emailMessageId' => 'msg_123'
+        ])
+      ));
+
+    $result = $this->client->campaigns->update(
+      campaign_id: $campaignId,
+      name: 'Spring announcement',
+      audience_filter: null
+    );
+
+    $this->assertTrue($result['success']);
+  }
 }
diff --git a/tests/EmailMessagesTest.php b/tests/EmailMessagesTest.php
index 4b8e5ed..2180711 100644
--- a/tests/EmailMessagesTest.php
+++ b/tests/EmailMessagesTest.php
@@ -51,19 +51,19 @@ public function testFindEmailMessage(): void
   public function testUpdateEmailMessage(): void
   {
     $emailMessageId = 'msg_123';
-    $fields = [
-      'expectedRevisionId' => 'rev_123',
-      'subject' => 'Updated subject',
-      'lmx' => '<Email><Text>Hello</Text></Email>'
-    ];
+    $lmx = '<Email><Text>Hello</Text></Email>';
 
     $this->mockHttpClient
       ->expects($this->once())
       ->method('post')
       ->with(
         'v1/email-messages/' . $emailMessageId,
-        $this->callback(function ($options) use ($fields) {
-          return $options['json'] === $fields;
+        $this->callback(function ($options) use ($lmx) {
+          return $options['json'] === [
+            'expectedRevisionId' => 'rev_123',
+            'subject' => 'Updated subject',
+            'lmx' => $lmx,
+          ];
         })
       )
       ->willReturn(new Response(
@@ -77,7 +77,7 @@ public function testUpdateEmailMessage(): void
           'fromName' => 'Loops',
           'fromEmail' => 'hello',
           'replyToEmail' => '',
-          'lmx' => $fields['lmx'],
+          'lmx' => $lmx,
           'contentRevisionId' => 'rev_456',
           'updatedAt' => '2025-01-02T00:00:00.000Z'
         ])
@@ -85,7 +85,9 @@ public function testUpdateEmailMessage(): void
 
     $result = $this->client->emailMessages->update(
       email_message_id: $emailMessageId,
-      fields: $fields
+      expected_revision_id: 'rev_123',
+      subject: 'Updated subject',
+      lmx: $lmx
     );
 
     $this->assertEquals('Updated subject', $result['subject']);
diff --git a/tests/UtilTest.php b/tests/UtilTest.php
index 618964c..6e36b76 100644
--- a/tests/UtilTest.php
+++ b/tests/UtilTest.php
@@ -2,6 +2,7 @@
 
 namespace Tests;
 
+use Loops\Core;
 use Loops\Util;
 use PHPUnit\Framework\TestCase;
 
@@ -36,4 +37,25 @@ public function testOmitNullKeepsFalsyNonNullValues(): void
       'count' => 0,
     ], $result);
   }
+
+  public function testOmitUnsetRemovesUnsetValues(): void
+  {
+    $result = Util::omitUnset([
+      'name' => 'Updated',
+      'mailingListId' => Core::UNSET,
+      'audienceFilter' => Core::UNSET,
+    ]);
+
+    $this->assertEquals(['name' => 'Updated'], $result);
+  }
+
+  public function testOmitUnsetKeepsExplicitNull(): void
+  {
+    $result = Util::omitUnset([
+      'mailingListId' => null,
+      'audienceFilter' => Core::UNSET,
+    ]);
+
+    $this->assertEquals(['mailingListId' => null], $result);
+  }
 }

From e967176ef02c0925da2c67e0640680b7040d4765 Mon Sep 17 00:00:00 2001
From: Dan <dan@loops.so>
Date: Fri, 26 Jun 2026 16:08:24 +0300
Subject: [PATCH 13/13] Update CHANGELOG.md

---
 CHANGELOG.md | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e801204..5443634 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,8 @@
-## v3.1.0 - Jun 24, 2026
+## v3.1.0 - Jun 26, 2026
 
 Added support for new content endpoints:
 
+- Breaking change: `emailMessages->update()` now has named parameters.
 - `uploads->upload()` for uploading images.
 - `transactional->create()`, `transactional->get()`, `transactional->update()`, `transactional->ensureDraft()`, and `transactional->publish()` for managing transactional emails.
 - `audienceSegments->list()` and `audienceSegments->get()` for audience segments.
@@ -10,6 +11,7 @@ Added support for new content endpoints:
 - `transactionalGroups->list()`, `transactionalGroups->create()`, `transactionalGroups->get()`, and `transactionalGroups->update()` for transactional groups.
 - `emailMessages->preview()` for sending test email previews.
 - Extended `campaigns->create()` and `campaigns->update()` with audience, group, and scheduling fields.
+- Requires PHP 8.1.
 
 ## v3.0.0 - May 19, 2026