[Bug]: Fetching Tools From MCP lacks logs

[brumar]

🐞 Bug Summary

After initiating the oauth2 consent flow (user delegation) with the notion MCP, I got this error when fetching tools and nothing in the logs either (even with loglevel at DEBUG).

❌ Retry Fetch Tools
❌ Failed to Fetch Tools
Error: Failed to fetch tools: Failed to fetch tools after OAuth: 
unhandled errors in a TaskGroup (1 sub-exception)

The logs seemed to say that fetching worked but validation failed, without more informations.

My own problem is solved because I realized notion schema are quite nested and increase
VALIDATION_MAX_JSON_DEPTH to 50.

I did not fill all the redtape so this issue can be closed, my most important priority was to help the next person after me that will be annoyed by making notion mcp work through the gateway.

[Shahzaibyy]

@brumar should i start with this

[brumar]

@Shahzaibyy I don't think I can decide? Maybe you wanted to mention something else?

But I think you can reproduce the error by trying to use the notion mcp with low VALIDATION_MAX_JSON_DEPTH and try to better handling errors in the async tasks or add more logs?

[Shahzaibyy]

@brumar Sorry for the mention - I was working on issue #1505 (uv support) and mentioned you by mistake. Thanks for the suggestions on #1542 though!

[Shahzaibyy]

Hi @brumar , I researched issue #1542 and found that Notion MCP schemas exceed the default JSON depth limit. Here's what I implemented:

Solution:

1. Increased depth limit: Default from 10 → 30, configurable via VALIDATION_MAX_JSON_DEPTH
2. Better error handling: Per-tool validation with logging instead of silent failures
3. User-friendly OAuth errors: Clear messages when validation fails during OAuth flows

Result: Users will now see helpful error messages instead of "unhandled errors in TaskGroup", and Notion MCP should work out-of-the-box.

Looking forward to your review of these changes!