Add path variables documentation for HTTP client

general/api-client/send-api-request.mdx

@@ -2,15 +2,15 @@
 title: "Send API Request"
 label: "Send API Request"
 slug: "send-api-request"
 description: "Simplify API testing with Requestly. Send HTTP requests, view responses, and add parameters."
 seoTitle: "Send API Request"
 seoDescription: "Simplify API testing with Requestly. Send HTTP and GraphQL requests, view responses, and add parameters."
 visibility: "PUBLIC"
 ---
 
 ---
 
 The API client in Requestly allows you to easily send API requests, without the need for writing code or using a terminal. It lets you test APIs, retrieve data, and explore how they work by simply creating a request, clicking Send, and viewing the response within Requestly.
 
 This feature is perfect for developers testing API endpoints during development, QA engineers validating API responses for edge cases, and support engineers debugging API issues in real-time.
 
@@ -92,6 +92,33 @@
 
 ---
 
+## Path Variables
+
+Path variables allow you to define dynamic segments in your API URL using the `:variableName` syntax. This is useful for RESTful APIs where resource identifiers are part of the URL path.
+
+For example, if your API endpoint is:
+```
+https://api.example.com/users/:userId/posts/:postId
+```
+
+Requestly automatically detects the path variables (`:userId` and `:postId`) from the URL and displays them in the **Params** tab under **Path Variables**. You can then set values for each variable:
+
+| Key | Value | Description |
+|-----|-------|-------------|
+| userId | 123 | The user's unique identifier |
+| postId | 456 | The post's unique identifier |
+
+When you send the request, Requestly compiles the URL with your provided values:
+```
+https://api.example.com/users/123/posts/456
+```
+
+<Tip>
+  Path variables are automatically extracted from your URL. Simply type a URL with `:variableName` segments, and they'll appear in the Path Variables table for you to fill in.
+</Tip>
+
+---
+
 ## Query Parameters
 
 In the **Query Params** section, you can add query parameters as **key-value pairs** to send extra information with the URL. To add more parameters, click on the `+ Add More` button.