We’ve been setting up the Discourse MCP server to connect our Discourse instance to Claude Desktop via config files. When using a single-use API key with granular access controls, the MCP server throws a 403 Forbidden error because it can’t read about.json. Snippet from the Console Logs [2026-03-18T12:09:13.703Z] INFO Starting Discourse MCP v0.2.6 [2026-03-18T12:09:16.679Z] ERROR HTTP 403 Forbidden for GET ``https://qna.tax/about.json:`` {“errors”:[“You are not permitted to view the requested resource. The API username or key is invalid.”],“error_type”:“invalid_access”} [2026-03-18T12:09:16.679Z] ERROR Failed to validate --site ``https://qna.tax``: HTTP 403 Forbidden There is no option anywhere to grant or revoke read access to “about” on granular permission. [image] Current workaround: Switching to a global API key (not scoped) resolves the 403 — but that’s not viable for any production setup where least-privilege access matters. Either about.json should be accessible to any valid API key regardless of scope (since it’s public site metadata), or the granular permissions UI should include an explicit option to whitelist it.

it seems reasonable to include access to about.json, I’ve opened a PR and will run this by the team https://github.com/discourse/discourse/pull/38948

[image] aangi: The API username or key is invalid Also, is this a misleading error we can improve?

Hi Michael, it does seem like a misleading error. However, because we cannot change the scope of the user once its been created, it is possible that in case of granular access, the API username is being rendered invalid because there is no about.json file.

Hi @awesomerobot @supermathie any update on this?

I’ve merged the change, so once it hits tests-passed you can rebuild and pull in the updated version and everything should work.

API user with granular access cannot read about.json | Discourse MCP

Product Support

supermathie (Michael Brown) March 29, 2026, 3:11am 4

Also, is this a misleading error we can improve?

Topic		Replies	Views
Request ESR backport: Allow granular API keys access to about.json Development mcp	2	175	July 28, 2026
Confirming API Access to Authoring Limit Site Settings Development rest-api	4	292	July 25, 2026
User API keys specification Integrations rest-api , reference	69	38710	September 22, 2025
Allow API use by regular users, not just admins Development rest-api	6	1674	February 14, 2023
Feature request: Allow safe API access to site settings without an admin-level key Feature rest-api	9	350	July 27, 2026

API user with granular access cannot read about.json | Discourse MCP

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