updated mcp tools docs (#376)

Author: ramsrib

fern/tools/mcp.mdx

@@ -144,6 +144,27 @@ Zapier offers an MCP server that provides access to thousands of app integration
   Zapier MCP provides access to over 7,000+ apps and 30,000+ actions without requiring complex API integrations.
 </Note>
 
+### Composio MCP
+
+Composio also offers an MCP server for integration:
+
+1. Log in to the Composio dashboard at https://mcp.composio.dev/dashboard
+2. Select the tool you want to integrate (e.g., Gmail)
+3. Enable the MCP server for the selected tool by connecting your account using authentication flow
+4. Create a server and copy the generated URL
+5. Add this URL to your MCP tool configuration as the `serverUrl`
+6. Your assistant will now have access to the specific Composio tool integration
+
+<Note type="warning">
+  **Context Overflow Warning**: Some MCP server tool calls (eg: GitHub API queries) may return large amounts of data. This can exceed model context limits, affecting assistant performance and potentially causing failures, especially with models like GPT-4o.
+
+  **Best Practices**:
+  - Configure your MCP tools to return focused, relevant data
+  - Use filtering parameters when available to limit response size
+  - Test your integration with realistic queries before deploying
+  - Monitor token usage and context size during development
+</Note>
+
 ## References
 
 - [Model Context Protocol Introduction](https://modelcontextprotocol.io/introduction)