[BUG] windows - Incompatible auth server: doe not support dynamic client registration - OpenCode

[mynameistito]

Describe the bug

I have got an issue on OpenCode - "Incompatible auth server: doe not support dynamic client registration"

Affected version

Steps to reproduce the behavior

1. add following to ~/.config/opencode.json

"mcp" {
    "github": {
      "type": "remote",
      "url": "https://api.githubcopilot.com/mcp/",
      "headers": {
        "Authorization": "Bearer {env:GITHUB_API_KEY}"
      },
      "enabled": true
    },
}

Expected vs actual behavior

Worked previously, unsure specifically where it regressed. however it worked previously.

Logs

OpenCode mcp test:

~\mynameistito opencode mcp debug github --print-logs --log-level DEBUG
INFO  2026-04-18T16:56:32 +513ms service=server-proxy version=1.4.12 args=["mcp","debug","github","--print-logs","--log-level","DEBUG"] process_role=main run_id=8f4aa8e5-4f05-4b0e-ad95-d20f13f6511b opencode
INFO  2026-04-18T16:56:32 +1ms service=server-proxy directory=C:\Users\mynameistito creating instance
INFO  2026-04-18T16:56:32 +6ms service=project directory=C:\Users\mynameistito fromDirectory
INFO  2026-04-18T16:56:32 +35ms service=db path=C:\Users\mynameistito\.local\share\opencode\opencode.db opening database
INFO  2026-04-18T16:56:32 +5ms service=db count=12 mode=bundled applying migrations

┌  MCP OAuth Debug
INFO  2026-04-18T16:56:32 +30ms service=file init
INFO  2026-04-18T16:56:32 +54ms service=config path=C:\Users\mynameistito\.config\opencode\config.json loading
INFO  2026-04-18T16:56:32 +2ms service=config path=C:\Users\mynameistito\.config\opencode\opencode.json loading
INFO  2026-04-18T16:56:32 +0ms service=config path=C:\Users\mynameistito\.config\opencode\opencode.jsonc loading
│
●  Server: github
│
●  URL: https://api.githubcopilot.com/mcp/
│
●  Auth status: ✗ not authenticated
│
◇  HTTP response: 401 Unauthorized
│
●  WWW-Authenticate: Bearer error="invalid_request", error_description="No access token was provided in this request", resource_metadata="https://api.githubcopilot.com/.well-known/oauth-protected-resource/mcp/"
│
▲  Server returned 401 Unauthorized
│
●  Testing OAuth flow (without completing authorization)...
│
■  Connection error: Incompatible auth server: does not support dynamic client registration
│
└  Debug complete

~\mynameistito

IIRC it did fail in the mcp debug prior, so that is potentially not a mpc issue thingy.

Env:

Windows 11 Pro Insider Preview 26220.8271
Windows Terminal 1.24.x, Windows Terminal Preview 1.25.x

[SamMorrowDrums]

Hi @mynameistito the best thing to do is create a GitHub Oauth App yourself instead. We don't support DCR, and don't support CIMD yet either.

https://opencode.ai/docs/mcp-servers/#pre-registered

You can also use a PAT token and we have docs in our repo, but the app route is the fastest path to the best experience and safety.

[mynameistito]

Hey @SamMorrowDrums, thanks for the zoomy reply, is that something new? I swear it worked recently is this a change in the latest MCP update?

Also regarding scopes I assume those just follow the normal git scopes, or should tools:read tools:execute give me everything?

I asume "scope" on the oauth would just be for the "x-oauth-scopes" ? (for OC)