Rentman MCP – Inconsistent Access Between Chats and Clients
I’m testing the Rentman MCP integration and seeing inconsistent behaviour across ChatGPT sessions.
What I’m seeing:
- Rentman MCP appears connected and available.
- In some chats, ChatGPT can successfully access live Rentman data (projects, inventory folders, stock locations, etc.).
- In other chats, ChatGPT can see the Rentman MCP tools/endpoints but cannot retrieve any actual account data.
- The model appears aware that Rentman exists but behaves as if authentication to the Rentman account has not completed.
Previous symptoms:
- Initially received:
Rentman unavailable{"error":"invalid_client","error_description":"Invalid client_id"}
- My Rentman account was using Microsoft SSO.
- Disabling SSO and allowing direct Rentman login appeared to improve things.
Current behaviour:
- Within the same ChatGPT account:
- Some conversations have been able to return live Rentman project information.
- Other conversations can only see the MCP tool definitions and cannot access live data.
- The behaviour appears inconsistent between conversations and possibly between ChatGPT clients (web, desktop app, mobile app), although this has been difficult to verify conclusively.
Example:
- Asking “What is my next Rentman project?” sometimes returns live project data.
- In another chat, ChatGPT states it can see the Rentman MCP tools but cannot retrieve any project information.
- Asking for inventory folders produces the same result.
Observation:
It feels as though MCP discovery and MCP authentication may be in different states. ChatGPT can sometimes see that the Rentman MCP is installed while not actually having a valid authenticated session to access the Rentman account data.
Question for the MCP team:
Is MCP authentication cached per chat, per client, or per user session? Could there be a state where tool discovery succeeds but the underlying OAuth/account token is no longer valid?