diff --git a/src/Actions/Responses/OutputObjects.php b/src/Actions/Responses/OutputObjects.php
index fca94ba6..de7955d5 100644
--- a/src/Actions/Responses/OutputObjects.php
+++ b/src/Actions/Responses/OutputObjects.php
@@ -5,6 +5,7 @@
 namespace OpenAI\Actions\Responses;
 
 use OpenAI\Responses\Responses\Output\OutputCodeInterpreterToolCall;
+use OpenAI\Responses\Responses\Output\OutputCompaction;
 use OpenAI\Responses\Responses\Output\OutputComputerToolCall;
 use OpenAI\Responses\Responses\Output\OutputCustomToolCall;
 use OpenAI\Responses\Responses\Output\OutputFileSearchToolCall;
@@ -32,13 +33,14 @@
  * @phpstan-import-type OutputMcpCallType from OutputMcpCall
  * @phpstan-import-type OutputImageGenerationToolCallType from OutputImageGenerationToolCall
  * @phpstan-import-type OutputCodeInterpreterToolCallType from OutputCodeInterpreterToolCall
+ * @phpstan-import-type OutputCompactionType from OutputCompaction
  * @phpstan-import-type OutputLocalShellCallType from OutputLocalShellCall
  * @phpstan-import-type OutputCustomToolCallType from OutputCustomToolCall
  * @phpstan-import-type OutputToolSearchCallType from OutputToolSearchCall
  * @phpstan-import-type OutputToolSearchOutputType from OutputToolSearchOutput
  *
- * @phpstan-type ResponseOutputObjectTypes array<int, OutputComputerToolCallType|OutputFileSearchToolCallType|OutputFunctionToolCallType|OutputMessageType|OutputReasoningType|OutputWebSearchToolCallType|OutputMcpListToolsType|OutputMcpApprovalRequestType|OutputMcpCallType|OutputImageGenerationToolCallType|OutputCodeInterpreterToolCallType|OutputLocalShellCallType|OutputCustomToolCallType|OutputToolSearchCallType|OutputToolSearchOutputType>
- * @phpstan-type ResponseOutputObjectReturnType array<int, OutputMessage|OutputComputerToolCall|OutputFileSearchToolCall|OutputWebSearchToolCall|OutputFunctionToolCall|OutputReasoning|OutputMcpListTools|OutputMcpApprovalRequest|OutputMcpCall|OutputImageGenerationToolCall|OutputCodeInterpreterToolCall|OutputLocalShellCall|OutputCustomToolCall|OutputToolSearchCall|OutputToolSearchOutput>
+ * @phpstan-type ResponseOutputObjectTypes array<int, OutputComputerToolCallType|OutputFileSearchToolCallType|OutputFunctionToolCallType|OutputMessageType|OutputReasoningType|OutputWebSearchToolCallType|OutputMcpListToolsType|OutputMcpApprovalRequestType|OutputMcpCallType|OutputImageGenerationToolCallType|OutputCodeInterpreterToolCallType|OutputLocalShellCallType|OutputCustomToolCallType|OutputToolSearchCallType|OutputToolSearchOutputType|OutputCompactionType>
+ * @phpstan-type ResponseOutputObjectReturnType array<int, OutputMessage|OutputComputerToolCall|OutputFileSearchToolCall|OutputWebSearchToolCall|OutputFunctionToolCall|OutputReasoning|OutputMcpListTools|OutputMcpApprovalRequest|OutputMcpCall|OutputImageGenerationToolCall|OutputCodeInterpreterToolCall|OutputLocalShellCall|OutputCustomToolCall|OutputToolSearchCall|OutputToolSearchOutput|OutputCompaction>
  */
 final class OutputObjects
 {
@@ -49,7 +51,7 @@ final class OutputObjects
     public static function parse(array $outputItems): array
     {
         return array_map(
-            fn (array $item): OutputMessage|OutputComputerToolCall|OutputFileSearchToolCall|OutputWebSearchToolCall|OutputFunctionToolCall|OutputReasoning|OutputMcpListTools|OutputMcpApprovalRequest|OutputMcpCall|OutputImageGenerationToolCall|OutputCodeInterpreterToolCall|OutputLocalShellCall|OutputCustomToolCall|OutputToolSearchCall|OutputToolSearchOutput => match ($item['type']) {
+            fn (array $item): OutputMessage|OutputComputerToolCall|OutputFileSearchToolCall|OutputWebSearchToolCall|OutputFunctionToolCall|OutputReasoning|OutputMcpListTools|OutputMcpApprovalRequest|OutputMcpCall|OutputImageGenerationToolCall|OutputCodeInterpreterToolCall|OutputLocalShellCall|OutputCustomToolCall|OutputToolSearchCall|OutputToolSearchOutput|OutputCompaction => match ($item['type']) {
                 'message' => OutputMessage::from($item),
                 'file_search_call' => OutputFileSearchToolCall::from($item),
                 'function_call' => OutputFunctionToolCall::from($item),
@@ -65,6 +67,7 @@ public static function parse(array $outputItems): array
                 'custom_tool_call' => OutputCustomToolCall::from($item),
                 'tool_search_call' => OutputToolSearchCall::from($item),
                 'tool_search_output' => OutputToolSearchOutput::from($item),
+                'compaction' => OutputCompaction::from($item),
                 default => throw new \UnexpectedValueException('Uh oh! We do not recognize this type. Please submit a bug to openai-php/client on GitHub!'),
             },
             $outputItems,
diff --git a/src/Responses/Responses/CreateResponse.php b/src/Responses/Responses/CreateResponse.php
index 6c4a7852..9078a76f 100644
--- a/src/Responses/Responses/CreateResponse.php
+++ b/src/Responses/Responses/CreateResponse.php
@@ -14,6 +14,7 @@
 use OpenAI\Responses\Concerns\HasMetaInformation;
 use OpenAI\Responses\Meta\MetaInformation;
 use OpenAI\Responses\Responses\Output\OutputCodeInterpreterToolCall;
+use OpenAI\Responses\Responses\Output\OutputCompaction;
 use OpenAI\Responses\Responses\Output\OutputComputerToolCall;
 use OpenAI\Responses\Responses\Output\OutputCustomToolCall;
 use OpenAI\Responses\Responses\Output\OutputFileSearchToolCall;
@@ -195,7 +196,7 @@ public function toArray(): array
             'metadata' => $this->metadata ?? [],
             'model' => $this->model,
             'output' => array_map(
-                fn (OutputMessage|OutputComputerToolCall|OutputFileSearchToolCall|OutputWebSearchToolCall|OutputFunctionToolCall|OutputReasoning|OutputMcpListTools|OutputMcpApprovalRequest|OutputMcpCall|OutputImageGenerationToolCall|OutputCodeInterpreterToolCall|OutputLocalShellCall|OutputCustomToolCall|OutputToolSearchCall|OutputToolSearchOutput $output): array => $output->toArray(),
+                fn (OutputMessage|OutputComputerToolCall|OutputFileSearchToolCall|OutputWebSearchToolCall|OutputFunctionToolCall|OutputReasoning|OutputMcpListTools|OutputMcpApprovalRequest|OutputMcpCall|OutputImageGenerationToolCall|OutputCodeInterpreterToolCall|OutputLocalShellCall|OutputCustomToolCall|OutputToolSearchCall|OutputToolSearchOutput|OutputCompaction $output): array => $output->toArray(),
                 $this->output
             ),
             'parallel_tool_calls' => $this->parallelToolCalls,
diff --git a/src/Responses/Responses/Output/OutputCompaction.php b/src/Responses/Responses/Output/OutputCompaction.php
new file mode 100644
index 00000000..cfb1b47b
--- /dev/null
+++ b/src/Responses/Responses/Output/OutputCompaction.php
@@ -0,0 +1,60 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenAI\Responses\Responses\Output;
+
+use OpenAI\Contracts\ResponseContract;
+use OpenAI\Responses\Concerns\ArrayAccessible;
+use OpenAI\Testing\Responses\Concerns\Fakeable;
+
+/**
+ * @phpstan-type OutputCompactionType array{id: string, encrypted_content: string, type: 'compaction', created_by?: string|null}
+ *
+ * @implements ResponseContract<OutputCompactionType>
+ */
+final class OutputCompaction implements ResponseContract
+{
+    /**
+     * @use ArrayAccessible<OutputCompactionType>
+     */
+    use ArrayAccessible;
+
+    use Fakeable;
+
+    /**
+     * @param  'compaction'  $type
+     */
+    private function __construct(
+        public readonly string $id,
+        public readonly string $encryptedContent,
+        public readonly string $type,
+        public readonly ?string $createdBy,
+    ) {}
+
+    /**
+     * @param  OutputCompactionType  $attributes
+     */
+    public static function from(array $attributes): self
+    {
+        return new self(
+            id: $attributes['id'],
+            encryptedContent: $attributes['encrypted_content'],
+            type: $attributes['type'],
+            createdBy: $attributes['created_by'] ?? null,
+        );
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function toArray(): array
+    {
+        return [
+            'id' => $this->id,
+            'encrypted_content' => $this->encryptedContent,
+            'type' => $this->type,
+            'created_by' => $this->createdBy,
+        ];
+    }
+}
diff --git a/src/Responses/Responses/RetrieveResponse.php b/src/Responses/Responses/RetrieveResponse.php
index 2c1d9909..aab18991 100644
--- a/src/Responses/Responses/RetrieveResponse.php
+++ b/src/Responses/Responses/RetrieveResponse.php
@@ -14,6 +14,7 @@
 use OpenAI\Responses\Concerns\HasMetaInformation;
 use OpenAI\Responses\Meta\MetaInformation;
 use OpenAI\Responses\Responses\Output\OutputCodeInterpreterToolCall;
+use OpenAI\Responses\Responses\Output\OutputCompaction;
 use OpenAI\Responses\Responses\Output\OutputComputerToolCall;
 use OpenAI\Responses\Responses\Output\OutputCustomToolCall;
 use OpenAI\Responses\Responses\Output\OutputFileSearchToolCall;
@@ -195,7 +196,7 @@ public function toArray(): array
             'metadata' => $this->metadata ?? [],
             'model' => $this->model,
             'output' => array_map(
-                fn (OutputMessage|OutputComputerToolCall|OutputFileSearchToolCall|OutputWebSearchToolCall|OutputFunctionToolCall|OutputReasoning|OutputMcpListTools|OutputMcpApprovalRequest|OutputMcpCall|OutputImageGenerationToolCall|OutputCodeInterpreterToolCall|OutputLocalShellCall|OutputCustomToolCall|OutputToolSearchCall|OutputToolSearchOutput $output): array => $output->toArray(),
+                fn (OutputMessage|OutputComputerToolCall|OutputFileSearchToolCall|OutputWebSearchToolCall|OutputFunctionToolCall|OutputReasoning|OutputMcpListTools|OutputMcpApprovalRequest|OutputMcpCall|OutputImageGenerationToolCall|OutputCodeInterpreterToolCall|OutputLocalShellCall|OutputCustomToolCall|OutputToolSearchCall|OutputToolSearchOutput|OutputCompaction $output): array => $output->toArray(),
                 $this->output
             ),
             'output_text' => $this->outputText,
diff --git a/tests/Fixtures/Responses.php b/tests/Fixtures/Responses.php
index 5dfb701e..36fd6a2a 100644
--- a/tests/Fixtures/Responses.php
+++ b/tests/Fixtures/Responses.php
@@ -983,6 +983,19 @@ function outputToolSearchOutput(): array
     ];
 }
 
+/**
+ * @return array<string, mixed>
+ */
+function outputCompaction(): array
+{
+    return [
+        'id' => 'cmp_67ccf18f64008190a39b619f4c8455ef087bb177ab789d5c',
+        'encrypted_content' => 'encrypted_string_value',
+        'type' => 'compaction',
+        'created_by' => 'user_123',
+    ];
+}
+
 /**
  * @return resource
  */
diff --git a/tests/Responses/Responses/Output/OutputCompaction.php b/tests/Responses/Responses/Output/OutputCompaction.php
new file mode 100644
index 00000000..b75ab96f
--- /dev/null
+++ b/tests/Responses/Responses/Output/OutputCompaction.php
@@ -0,0 +1,39 @@
+<?php
+
+use OpenAI\Responses\Responses\Output\OutputCompaction;
+
+test('from', function () {
+    $response = OutputCompaction::from(outputCompaction());
+
+    expect($response)
+        ->toBeInstanceOf(OutputCompaction::class)
+        ->id->toBe('cmp_67ccf18f64008190a39b619f4c8455ef087bb177ab789d5c')
+        ->encryptedContent->toBe('encrypted_string_value')
+        ->type->toBe('compaction')
+        ->createdBy->toBe('user_123');
+});
+
+test('from without created_by', function () {
+    $attributes = outputCompaction();
+    unset($attributes['created_by']);
+
+    $response = OutputCompaction::from($attributes);
+
+    expect($response)
+        ->toBeInstanceOf(OutputCompaction::class)
+        ->createdBy->toBeNull();
+});
+
+test('as array accessible', function () {
+    $response = OutputCompaction::from(outputCompaction());
+
+    expect($response['id'])->toBe('cmp_67ccf18f64008190a39b619f4c8455ef087bb177ab789d5c');
+});
+
+test('to array', function () {
+    $response = OutputCompaction::from(outputCompaction());
+
+    expect($response->toArray())
+        ->toBeArray()
+        ->toBe(outputCompaction());
+});