When your MCP server cannot be reached, the agent quietly answers without its tools and nothing shows in the chat. Use Test Connection to see the real reason and fix it.
Why chats look normal
If the server is down or slow, the agent drops the tools for that reply and answers with what it already knows. The customer sees a normal answer, so a broken connection can go unnoticed. Check it from settings, not from the chat.
Run Test Connection
On the connected MCP card, click Test Connection. This is the only place the real error appears. A failure reads like Failed to connect to MCP server followed by the reason, for example that the server could not be reached or that the request timed out after a few seconds.
Common causes
- The server is not reachable over public HTTPS.
- The server took too long to respond, so the request timed out.
- The server address is wrong.
- The auth key was rotated or revoked, so the server rejects the request.
Fix it
- Confirm your server is online and reachable over public HTTPS.
- Run Test Connection again.
- If it still fails, disconnect the server and connect again with the correct address and key.