MCP troubleshooting

The full MCP troubleshooting reference lives under the Claude Code section, since most MCP issues are client-side.

Open Claude Code troubleshooting →

Quick links to common MCP issues

• “MCP server failed to start” / “Cannot connect”
• “401 unauthorized” on every call
• “403 forbidden” on a specific tool
• “429 rate limited”
• Tools list is empty in the client
• Hosted endpoint issues
• “ticket not found”
• “I changed scopes but it still says forbidden”
• Captured data looks empty

Where to ask

If none of those help, get in touch. Include:

• The MCP client (Claude Code, Claude Desktop, Cursor, etc.) and version.
• The MCP config block, with the token redacted.
• Any stderr output from the server.