Error creating connector – Request timeout” for Public HTTPS MCP Server (Cloudflare Tunnel

ChatGPT
,
1

Hi,
I’m trying to add a custom MCP connector in ChatGPT Desktop (Microsoft Store version).
The connector is hosted locally but exposed publicly through Cloudflare Tunnel, so ChatGPT’s backend can reach it.

Everything works when tested externally, but ChatGPT always fails with:

Error creating connector
unhandled errors in a TaskGroup (1 sub-exception)

or

Request timeout

:white_check_mark: Environment

  • Windows 10/11

  • ChatGPT Desktop (Store version)

  • MCP server: Obsidian MCP Tools via custom HTTPS bridge (node mcp-https-bridge.js)

  • Local certificate created with mkcert (installed into LocalMachine trust store)

  • Public URL exposed through Cloudflare Tunnel

  • Developer Mode / Custom MCP Connectors enabled in ChatGPT settings

:white_check_mark: Public URL tested

https://treo-compiled-interfaces-unless.trycloudflare.com/.well-known/openapi.json

Direct tests (from outside my PC):

curl https://treo-compiled-interfaces-unless.trycloudflare.com/health
→ 200 OK {"ok": true}

curl https://treo-compiled-interfaces-unless.trycloudflare.com/.well-known/openapi.json
→ 200 OK valid OpenAPI spec

curl https://treo-compiled-interfaces-unless.trycloudflare.com/tools
→ 200 OK with full tool list (~9 KB)

So the tunnel works perfectly and is publicly reachable.
No TLS errors.
No CORS issues.
OpenAPI is valid.

:cross_mark: Issue: ChatGPT cannot add the connector

When adding the connector via:

https://treo-compiled-interfaces-unless.trycloudflare.com/.well-known/openapi.json

ChatGPT immediately fails with:

Error creating connector
unhandled errors in a TaskGroup (1 sub-exception)

or:

Request timeout

This happens even though:

  • The server is fully reachable from the public internet

  • The OpenAPI spec loads fine

  • /health, /tools, and /call all work

  • The connector URL is correct and HTTPS-valid

:red_question_mark: Expected behavior

ChatGPT should:

  1. Fetch /.well-known/openapi.json (works externally)

  2. Parse MCP spec

  3. Register the connector

Instead, it times out on the ChatGPT backend during connector creation.

:magnifying_glass_tilted_left: Suspected cause

A backend issue with ChatGPT’s MCP connector creation pipeline:
Several other users have reported identical symptoms recently — “Request timeout” when adding connectors that are otherwise fully reachable externally.

:folded_hands: Request

Could the team please check the backend logs for connector creation failures against the above domain?

Happy to provide more diagnostics if needed.
Everything on my side (TLS, tunneling, MCP, OpenAPI validation) is functioning properly.

Thanks!