MCP Community Server Tools NOT Invoked by AI Agent

[yizzy]

I have a self-hosted solution on CasaOS running on Debian 12.
I’d like to experiment with MCP community servers.
I installed the initial n8n node:

And I also included the environment varilable in my Docker instance.
(N8N_COMMUNITY_PACKAGES_ALLOW_TOOL_USAGE)
Then I tested it to make sure it was working.

Describe the problem/error/question

The AI Agent is not invoking the MCP server tools.

What is the error message (if any)?

No visible error – just won’t work as intended.

Please share your workflow

Share the output returned by the last node

Information on your n8n setup

• n8n version: 1.84.3
• Database (default: SQLite): PostgreSQL
• n8n EXECUTIONS_PROCESS setting (default: own, main): ?
• Running n8n via (Docker, npm, n8n cloud, desktop app): Docker
• Operating system: Debian 12

[jcuypers]

Hi, the list one should be the easiest

Try with putting a custom description on the MCP list stating “provides a list of services provided by the compass tool”

And try to run it. By prompting. Provide me a list of services by compass. I’m using openai. Never tried mistral. Are you sure it has support for it through n8n? I’ve reed somewhere that some models don’t support tools or don’t work well. I recommend trying openai

[yizzy]

Wow. It worked like a CHARM – thank you!

Now, I have to figure out a way to NOT use OpenAI…

Gemin is free and suits my needs… mostly.

[jcuypers]

Hi, well I cannot speak for anybody else, but if is for personal use and/or limited in size the costs are quite small. In addition, at any time the costs for a model can change. Lately I tried to create an additional key for gemini and i didn’t state “free” anymore for the same service. re-used the older ones which still indicated free for the same service. In the end everything will be paid, better to aim for solution that fits your needs as all the rest are hidden costs that quickly add up too