mcp iframe updates

mcp/LLM_USAGE_GUIDE.md

@@ -112,17 +112,21 @@ Switch iframe context for subsequent operations.
 - `action` (required): One of "enter", "exit"
 - `selector` (optional): Iframe CSS selector (required for "enter" action)
 - `tab` (optional): Specific tab ID to use
+- `timeout` (optional): Timeout in seconds (default: 5)
 
 **Example Usage:**
 ```
 web_iframe_cremotemcp:
   action: "enter"
   selector: "iframe#payment-form"
+  timeout: 10
 
 web_iframe_cremotemcp:
   action: "exit"
 ```
 
+**Note:** The timeout parameter is particularly important for iframe operations as they can hang if the iframe takes time to load or if the selector doesn't match any elements.
+
 ### 7. `file_upload_cremotemcp`
 Upload files from the client to the container for use in form uploads.