OAuth MCP server works in ChatGPT Developer Mode ("Create App") but fails in App Review form — what does "unsupported OAuth config type" really mean?

ChatGPT Apps SDK
1

Hi all,

I’m hoping someone can help me understand an error I’m hitting, and why the behavior differs between two OAuth flows in ChatGPT.

The Problem

With the same MCP server URL, with the same OAuth configuration:

  • :white_check_mark: Works perfectly when connected via chatgpt.com → Developer Mode → Create App. The server supports both pre-defined and DCR modes no problems!

  • :cross_mark: Fails in the App Review submission form at Step 2 (“MCP Server”) when clicking Scan Tools, with:

    MCP details save failed: OAuth discovery returned unsupported OAuth config type

Interestingly, “Scan Tools” on the review form worked fine for me on 21 April 2026 with a test (unpublished) app. The failure started showing up recent, on 6 May 2026 (attempts around ~05:00 and ~10:00 GMT+0800) against the same server.

What I’m trying to understand

  1. What does “OAuth discovery returned unsupported OAuth config type” actually mean? Which part of the OAuth discovery document is it reporting an error about?
  2. Why would the App Review form’s OAuth discovery treat a server differently from Developer Mode’s “Create App” flow, if both are ostensibly doing MCP OAuth discovery against the same URL?
  3. Is there a stricter OAuth metadata requirement on the review path (e.g. specific authorization_servers, PKCE, or dynamic client registration fields) that Developer Mode doesn’t enforce? I’m struggling to debug what’s going on ~

Reproduction

  1. Create a new App Review draft, fill in details up to Step 2: MCP Server
  2. MCP server URL: https://example.com/api/mcp
  3. Auth mode: OAuth
  4. Click Scan Tools → error dialog appears

Screenshot of the error dialog:

image
image1920×1207 149 KB

If anyone has shipped an OAuth-backed MCP server through App Review recently, I’d love to know what discovery-document shape worked for you — and whether the two flows are expected to diverge.

Thank you!!

2

I’m having similar issue. The backend log show the error happen after it hit “.well-known/openid-configuration”. Could be some validation errors but the message is not useful at this time.
Seems liked this is a new issues. Submitted another app a few days ago with the same oauth config and it was fine.

3

Happens as well, on a production app as we try to submit a new version of it.
It worked last week

4

Also experiencing this when doing the tool scan in draft

POST api.openai com /v1/dashapi/versions 500 (Internal Server Error)

5

I am able to reproduce the OAuth discovery returned unsupported OAuth config type error with 3 production Oauth MCP apps that work in “Dev mode” in ChatGPT, and in Goose, it generates an HTTP 500 error in the network tab . It happens both from a business and personal account.

https://mcp.atlassian.com/v1/mcp
https://mcp.linear.app/mcp
https://mcp.datadoghq.com/api/unstable/mcp-server/mcp

I think the error message is specific to Oauth apps, since no-auth servers ( mcp.excalidraw.com ) succeeds at the tool scan step without issue.

6

Hey folks, Max from the OpenAI Engineering team here. Thanks for the reports, we are actively investigating. I will post an update here when we have updates.

7

Update: this is now resolved!

Apologies for the trouble. We are in the middle of migrating our submissions API to some new infrastructure, and as part of this we had an incompatibility between the old and the new API that caused this issue.

Happy submitting, folks.

8

Thanks for the update!
By when should we expect to get these changes?

9

Update here, I was just able to use the scanner and submit for review