The Azure AI Foundry Agent Service is a component used to extend Microsoft 365 Copilot capabilities by integrating custom Machine Copilot (MCP) tools. However, subtle configuration details can cause failures. One such issue, experienced by a Microsoft 365 and Azure architect, highlights how assigning a friendly name to an MCP tool can cause the agent's operation to fail.

In this post, we explore the root cause behind the Azure AI Foundry Agent Service returning the error message:

Run failed: {'code': 'server_error', 'message': 'Sorry, something went wrong.'}

The problem appeared when using a custom-built MCP Server with multiple tools, where all tools worked except the one with a friendly name assigned. The exact reason why the friendly name causes failure is not confirmed, but removing the friendly name resolved the issue.

Key Observations

• Only the MCP tool with a friendly name failed while other tools functioned normally.
• The presence of a friendly name appears to cause the Agent Service to fail, though the exact cause (such as spaces in the name) is uncertain.
• The error message "Sorry, something went wrong." provides no direct diagnostic clues.

Resolution

Removing the friendly name from the tool definition resolved the error:

{
  "Name": "mycustomtool",
  "FriendlyName": null
}

This suggests that the Agent Service may not support MCP tools with friendly names.

Conclusion

When integrating custom MCP tools into the Azure AI Foundry Agent Service, avoid assigning friendly names to tools, as this can cause runtime failures with opaque error messages. Removing friendly names restores normal operation.

Reference

• Azure AI Foundry Agent Service Fails with MCP Tool Sorry, something went wrong - simondoy.com