Lots of people reported issues in the forums weeks ago, seems like they haven't improved it much (what's the point of doing a beta if you ignore everyone reporting bugs?)

https://community.openai.com/t/error-oauth-step-when-connect...

OpenAI is the biggest proof AI won't replace software engineers. They absolutely suck at shipping code

What is the error you are getting? I get "Error fetching OAuth configuration" with an MCP server that I can connect to via Claude.

I get this error trying to connect the Mapbox hosted MCP server:

    Something went wrong with setting up the connection

In the devtools, the request that failed was to `https://chatgpt.com/backend-api/aip/connectors/links/oauth/c...` which send this reply:

    Token exchange failed: 401, message='Unauthorized', url=URL('https://api.mapbox.com/oauth/access_token')

"error creating connector"

our MCP also works fine with Claude, Claude Code, Amp, lm studio and other but not all MCP clients

MCP spec and client implementations are a bit tricky when you're not using FastMCP (which we are not).

I wonder if it's a difference between SSE and HTTP streaming support? I've been working on a tool for devs to create their own MCP tools and built out support for both protocols because it was easier for me to support both protocols vs explaining why it's not working for one LLM client or another.

Oh, that might be it!

Ours doesn’t support SSE.

mine does support SSE (https://github.com/mickael-kerjean/filestash) but it fails before getting there, with the log looking like this:

    2025/09/11 01:16:13 HTTP 200 GET    0.1ms /.well-known/oauth-authorization-server
    2025/09/11 01:16:13 HTTP 200 GET    2.5ms /
    2025/09/11 01:16:14 HTTP 404 GET    0.2ms /favicon.svg
    2025/09/11 01:16:14 HTTP 404 GET    0.2ms /favicon.png
    2025/09/11 01:16:14 HTTP 200 GET    0.2ms /favicon.ico
    2025/09/11 01:16:14 HTTP 200 GET    0.1ms /.well-known/oauth-authorization-server
    2025/09/11 01:16:15 HTTP 201 POST    0.3ms /mcp/register
    2025/09/11 01:16:27 HTTP 200 GET    1.4ms /

with the frontend showing: "Error creating connector" and the network call showing: { "detail": "1 validation error for RegisterOAuthClientResponse\n Input should be a valid dictionary or instance of RegisterOAuthClientResponse [type=model_type, input_value='{\"client_id\":\"ChatGPT.Dd...client_secret_basic\"}\\n', input_type=str]\n For further information visit https://errors.pydantic.dev/2.11/v/model_type" }