WebFiori · usernane · Jun 1, 2026 · Jun 1, 2026 · Jun 1, 2026 · Jun 1, 2026
diff --git a/README.md b/README.md
@@ -411,6 +411,36 @@ public function getData(int $id, ?string $name): array {
 }
 ```
 
+### Reusable Parameter Sets
+
+Implement the `ParameterSet` interface to group related parameters:
+
+```php
+class PaginationParams implements ParameterSet {
+    public function getParameters(): array {
+        return [
+            'page' => [ParamOption::TYPE => ParamType::INT, ParamOption::OPTIONAL => true, ParamOption::DEFAULT => 1],
+            'per_page' => [ParamOption::TYPE => ParamType::INT, ParamOption::OPTIONAL => true, ParamOption::DEFAULT => 20],
+        ];
+    }
+}
+```
+
+Use with attributes:
+
+```php
+#[GetMapping]
+#[ResponseBody]
+#[UseParameterSet(PaginationParams::class)]
+public function listItems(int $page = 1, int $perPage = 20): array { ... }
+```
+
+Or traditionally:
+
+```php
+$this->addParameterSet(new PaginationParams());
+```
+
 ## Dynamic Status Codes with ResponseEntity
 
 The `ResponseEntity` class allows `#[ResponseBody]` methods to return different HTTP status codes based on runtime logic:

diff --git a/WebFiori/Http/Annotations/UseParameterSet.php b/WebFiori/Http/Annotations/UseParameterSet.php
@@ -0,0 +1,21 @@
+<?php
+
+/**
+ * This file is licensed under MIT License.
+ * 
+ * Copyright (c) 2026-present WebFiori Framework
+ * 
+ * For more information on the license, please visit: 
+ * https://github.com/WebFiori/.github/blob/main/LICENSE
+ */
+namespace WebFiori\Http\Annotations;
+
+use Attribute;
+
+#[Attribute(Attribute::TARGET_METHOD | Attribute::IS_REPEATABLE)]
+class UseParameterSet {
+    public function __construct(
+        public readonly string $class
+    ) {
+    }
+}
diff --git a/WebFiori/Http/OpenAPI/HeaderObj.php b/WebFiori/Http/OpenAPI/HeaderObj.php
@@ -27,7 +27,7 @@
  * 
  * @see https://spec.openapis.org/oas/v3.1.0#header-object
  */
-class HeaderObj implements JsonI {
+class HeaderObj extends OpenAPIObject implements JsonI {
     /**
      * Specifies that the header is deprecated and SHOULD be transitioned out of usage.
      * 
@@ -36,15 +36,6 @@ class HeaderObj implements JsonI {
      * @var bool
      */
     private bool $deprecated = false;
-    /**
-     * A brief description of the header.
-     * 
-     * This could contain examples of use.
-     * CommonMark syntax MAY be used for rich text representation.
-     * 
-     * @var string|null
-     */
-    private ?string $description = null;
 
     /**
      * Example of the header's potential value.
@@ -101,15 +92,6 @@ public function getDeprecated(): bool {
         return $this->deprecated;
     }
 
-    /**
-     * Returns the description.
-     * 
-     * @return string|null Returns the value, or null if not set.
-     */
-    public function getDescription(): ?string {
-        return $this->description;
-    }
-
     /**
      * Returns the example.
      * 
@@ -190,19 +172,6 @@ public function setDeprecated(bool $deprecated): HeaderObj {
         return $this;
     }
 
-    /**
-     * Sets the description of the header.
-     * 
-     * @param string $description A brief description of the header.
-     * 
-     * @return HeaderObj Returns self for method chaining.
-     */
-    public function setDescription(string $description): HeaderObj {
-        $this->description = $description;
-
-        return $this;
-    }
-
     /**
      * Sets an example of the header's potential value.
      * 
@@ -289,37 +258,14 @@ public function setStyle(string $style): HeaderObj {
     public function toJSON(): Json {
         $json = new Json();
 
-        if ($this->getDescription() !== null) {
-            $json->add('description', $this->getDescription());
-        }
-
-        if ($this->getRequired()) {
-            $json->add('required', $this->getRequired());
-        }
-
-        if ($this->getDeprecated()) {
-            $json->add('deprecated', $this->getDeprecated());
-        }
-
-        if ($this->getStyle() !== null) {
-            $json->add('style', $this->getStyle());
-        }
-
-        if ($this->getExplode() !== null) {
-            $json->add('explode', $this->getExplode());
-        }
-
-        if ($this->getSchema() !== null) {
-            $json->add('schema', $this->getSchema());
-        }
-
-        if ($this->getExample() !== null) {
-            $json->add('example', $this->getExample());
-        }
-
-        if ($this->getExamples() !== null) {
-            $json->add('examples', $this->getExamples());
-        }
+        $this->addIfNotNull($json, 'description', $this->getDescription());
+        $this->addIfTruthy($json, 'required', $this->getRequired());
+        $this->addIfTruthy($json, 'deprecated', $this->getDeprecated());
+        $this->addIfNotNull($json, 'style', $this->getStyle());
+        $this->addIfNotNull($json, 'explode', $this->getExplode());
+        $this->addIfNotNull($json, 'schema', $this->getSchema());
+        $this->addIfNotNull($json, 'example', $this->getExample());
+        $this->addIfNotNull($json, 'examples', $this->getExamples());
 
         return $json;
     }

diff --git a/WebFiori/Http/OpenAPI/OpenAPIObject.php b/WebFiori/Http/OpenAPI/OpenAPIObject.php
@@ -0,0 +1,58 @@
+<?php
+
+/**
+ * This file is licensed under MIT License.
+ * 
+ * Copyright (c) 2026-present WebFiori Framework
+ * 
+ * For more information on the license, please visit: 
+ * https://github.com/WebFiori/http/blob/master/LICENSE
+ */
+namespace WebFiori\Http\OpenAPI;
+
+use WebFiori\Json\Json;
+
+/**
+ * Base class for OpenAPI specification objects.
+ * 
+ * Provides common properties (description, deprecated, etc.) and a helper
+ * for building JSON output without repetitive null-checks.
+ *
+ * @author Ibrahim
+ */
+abstract class OpenAPIObject {
+    private ?string $description = null;
+
+    public function getDescription() : ?string {
+        return $this->description;
+    }
+
+    public function setDescription(string $description) : static {
+        $this->description = $description;
+        return $this;
+    }
+    /**
+     * Adds a value to a Json object only if it is not null.
+     * 
+     * @param Json $json The target Json object.
+     * @param string $key The JSON key.
+     * @param mixed $value The value to add.
+     */
+    protected function addIfNotNull(Json $json, string $key, mixed $value) : void {
+        if ($value !== null) {
+            $json->add($key, $value);
+        }
+    }
+    /**
+     * Adds a value to a Json object only if it is truthy (non-null, non-false, non-empty).
+     * 
+     * @param Json $json The target Json object.
+     * @param string $key The JSON key.
+     * @param mixed $value The value to add.
+     */
+    protected function addIfTruthy(Json $json, string $key, mixed $value) : void {
+        if (!empty($value)) {
+            $json->add($key, $value);
+        }
+    }
+}
diff --git a/WebFiori/Http/OpenAPI/ParameterObj.php b/WebFiori/Http/OpenAPI/ParameterObj.php
@@ -27,7 +27,7 @@
  * 
  * @see https://spec.openapis.org/oas/v3.1.0#parameter-object
  */
-class ParameterObj implements JsonI {
+class ParameterObj extends OpenAPIObject implements JsonI {
     /**
      * If true, clients MAY pass a zero-length string value in place of parameters 
      * that would otherwise be omitted entirely.
@@ -58,16 +58,6 @@ class ParameterObj implements JsonI {
      */
     private bool $deprecated = false;
 
-    /**
-     * A brief description of the parameter.
-     * 
-     * This could contain examples of use.
-     * CommonMark syntax MAY be used for rich text representation.
-     * 
-     * @var string|null
-     */
-    private ?string $description = null;
-
     /**
      * Example of the parameter's potential value.
      * 
@@ -176,15 +166,6 @@ public function getDeprecated(): bool {
         return $this->deprecated;
     }
 
-    /**
-     * Returns the description.
-     * 
-     * @return string|null Returns the value, or null if not set.
-     */
-    public function getDescription(): ?string {
-        return $this->description;
-    }
-
     /**
      * Returns the example.
      * 
@@ -325,19 +306,6 @@ public function setDeprecated(bool $deprecated): ParameterObj {
         return $this;
     }
 
-    /**
-     * Sets the description of the parameter.
-     * 
-     * @param string $description A brief description of the parameter.
-     * 
-     * @return ParameterObj Returns self for method chaining.
-     */
-    public function setDescription(string $description): ParameterObj {
-        $this->description = $description;
-
-        return $this;
-    }
-
     /**
      * Sets an example of the parameter's potential value.
      * 
@@ -457,45 +425,16 @@ public function toJSON(): Json {
             'in' => $this->getIn()
         ]);
 
-        if ($this->getDescription() !== null) {
-            $json->add('description', $this->getDescription());
-        }
-
-        if ($this->getRequired()) {
-            $json->add('required', $this->getRequired());
-        }
-
-        if ($this->getDeprecated()) {
-            $json->add('deprecated', $this->getDeprecated());
-        }
-
-        if ($this->getAllowEmptyValue()) {
-            $json->add('allowEmptyValue', $this->getAllowEmptyValue());
-        }
-
-        if ($this->getStyle() !== null) {
-            $json->add('style', $this->getStyle());
-        }
-
-        if ($this->getExplode() !== null) {
-            $json->add('explode', $this->getExplode());
-        }
-
-        if ($this->getAllowReserved() !== null) {
-            $json->add('allowReserved', $this->getAllowReserved());
-        }
-
-        if ($this->getSchema() !== null) {
-            $json->add('schema', $this->getSchema());
-        }
-
-        if ($this->getExample() !== null) {
-            $json->add('example', $this->getExample());
-        }
-
-        if ($this->getExamples() !== null) {
-            $json->add('examples', $this->getExamples());
-        }
+        $this->addIfNotNull($json, 'description', $this->getDescription());
+        $this->addIfTruthy($json, 'required', $this->getRequired());
+        $this->addIfTruthy($json, 'deprecated', $this->getDeprecated());
+        $this->addIfTruthy($json, 'allowEmptyValue', $this->getAllowEmptyValue());
+        $this->addIfNotNull($json, 'style', $this->getStyle());
+        $this->addIfNotNull($json, 'explode', $this->getExplode());
+        $this->addIfNotNull($json, 'allowReserved', $this->getAllowReserved());
+        $this->addIfNotNull($json, 'schema', $this->getSchema());
+        $this->addIfNotNull($json, 'example', $this->getExample());
+        $this->addIfNotNull($json, 'examples', $this->getExamples());
 
         return $json;
     }

diff --git a/WebFiori/Http/ParameterSet.php b/WebFiori/Http/ParameterSet.php
@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * This file is licensed under MIT License.
+ * 
+ * Copyright (c) 2026-present WebFiori Framework
+ * 
+ * For more information on the license, please visit: 
+ * https://github.com/WebFiori/http/blob/master/LICENSE
+ */
+namespace WebFiori\Http;
+
+/**
+ * Interface for grouping related request parameters into reusable sets.
+ * 
+ * Implement this interface to define a collection of parameters that can
+ * be shared across multiple web services.
+ *
+ * @author Ibrahim
+ */
+interface ParameterSet {
+    /**
+     * Returns an array of parameter definitions.
+     * 
+     * Each key is the parameter name and the value is an associative array
+     * of options compatible with WebService::addParameters().
+     * 
+     * @return array<string, array> Parameter definitions keyed by name.
+     */
+    public function getParameters(): array;
+}