Solution for mcp-ui can not call external tools
When mcp-ui fails to invoke an external tool, it may be due to a configuration error, a service not started, or a tool definition problem. The following are specific solutions:
- Check that the MCP service is functioning properly: Ensure that the MCP back-end service has been started (
npm run mcp:server), and check the terminal for reported errors. - Validation Tool Configuration: Inspection
mcp_server.jsin the tool list, make sure that the tool name, parameters and description are defined correctly, e.g. the browser tool needs to contain thename: "browser"The - Testing API connectivity: Type a simple command in the chat box (e.g. "Open Google Search AI"), and see if the tool call log is returned. If there is no response, it may be a port conflict (default 3001), you can change the following
.envhit the nail on the headMCP_SERVER_PORTThe - Checking dependencies: Run
npm lsVerify that all dependencies (e.g.@mcp/core) is installed and can be re-executed if missingnpm installThe
If the problem remains unresolved, try the following workarounds:
- Restart all services (front-end, back-end, Electron).
- Check the project's GitHub Issues page and search for similar issues.
- Check in the Network tab of the Developer Tools (F12) to see if the API requests are being sent properly.
This answer comes from the articlemcp-ui: a clean AI chat interface based on the MCP protocolThe
May not be reproduced without permission:AI productivity tools " How to solve the problem of not being able to call external tools in mcp-ui?
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