Power Platform Community Forum Thread Details

Hi team,

I create a MCP Server and would like to work add it as a tool in my custom agent.

But I don't get any error and response back.

Categories:

Hey @HW-13111933-0

To diagnose why the agent isn’t receiving responses, I’ll need a bit more detail about your setup.

Could you please share the following?
• The MCP server URL and transport type you’re using (Streamable required)
• How the server is hosted (local, cloud VM, container, etc.)
• A sample of the tool definitions you’re exposing (name, description, input schema)
• A sample of the JSON response your MCP server returns when a tool is called
• Whether the server logs show any request coming in from Copilot Studio
• Whether you used the MCP onboarding wizard or a custom connector
This will help narrow down where the issue is happening.

In the meantime, here’s a quick troubleshooting checklist you can review:

1. Confirm the MCP server is connected

In Copilot Studio → Tools, select your MCP server.
Make sure a connection is selected and showing no warnings.
Ensure tools appear in the Tools list. If the list is empty, there’s usually a handshake/schema issue.

2. Enable tools in the agent

Make sure Allow all is ON, or
If it’s OFF, toggle ON at least one tool manually.
If all tools are disabled, the agent won’t attempt any MCP call.

3. Test the connection independently

If you used the onboarding wizard, use the built-in Test button to call a tool directly.
If you used a custom connector, open it in Power Apps → Test.

4. Check tool activity during testing

In the agent’s Test pane, open the Activity/Tools view.
Trigger a prompt that should use your MCP tool and see if a tool call is made.
If there is a call but no output, the issue is likely in the server response.

5. Validate the MCP tool implementation

Tools must include a name, description, and input schema.
Responses must include content the model can surface (e.g., a text message).
Ensure resources are configured correctly if you return files or structured outputs.

6. Try a minimal tool
If nothing surfaces, try exposing a simple test tool that returns a static string such as “Hello from MCP”. This helps isolate integration issues.

Here are a few helpful Microsoft Learn resources:
• Build and connect MCP tools in Copilot Studio

• MCP Server and Tool Protocol Overview

• Troubleshooting and validating tool responses