Agenda MCP not connecting on Claude Desktop for Mac

Support
1

What I did: Started the latest version of Claude Desktop for Mac on MacOS 27 (this issue has been around in MacOS 26 as well). I disabled and re-enabled the Agenda Connector. No change; still unable to connect. I reinstalled the Agenda connector. No change; still unable to connect. I restarted machine; no change still unable to connect.

What happened: Claude shows this error message: MCP Agenda: Couldn’t start for Cowork and Code sessions. Error: Agenda is not reachable. Connection refused. Please open Agenda and enable the MCP server via Agenda > Integrations > Enable MCP. AGENDA_MCP_PORT=16106

What I expected: Claude to be able to connect to Agenda. Instead connection is unable to be established.

Things that might be helpful to know (Agenda version, OS and model, etc): Agenda Version 23.3.2 (425); MacOS 27.0; Claude 2.2553.1 (c38127) 2026-09-18T00:41:58.000Z

2

Happened to me too. I realized that Agenda has to be open before Claude. Hope this helps.

3

Oh, fantastic! That fixed it! For some reason, I always started Claude first and never put two and two together. Starting Agenda first and then starting Claude fixed the issue.

Thank you!

4

I think you might be able to use the /mcp command in Claude to refresh the connection once Agenda is launched. Not 100% sure.

5

I’m glad you figured it out. I was coming here to say to start Agenda first. I have to mention that having Claude integrated with Agenda, Tinderbox, DEVONthink, Calendar 366, and Curio has been a game changer for me; I’m amazed at what it can do and the time it saves. If only I would quit playing with all of it and focus on grading all these doggone discussion boards.

6

Yes, the MCP server in Agenda runs only when Agenda is running.

You could launch claude before Agenda, but then you have to get claude to rescan for MCP servers. It will have registered that Agenda’s MCP server is disconnected. I think the claude /mcp command can help.