"Incompatible auth server: does not support dynamic client registration" in Claude Code MCP. Fix: add the server with --client-id

Error (claude mcp list, /mcp, or the sign-in step for a remote MCP server):

Incompatible auth server: does not support dynamic client registration

Seen with: GitHub's remote MCP server (https://api.githubcopilot.com/mcp), Slack (https://mcp.slack.com/mcp), Box, AWS Cognito in front of Bedrock AgentCore gateways, Microsoft Entra ID.

Cause: by default Claude Code registers itself with the server's sign-in service (Dynamic Client Registration). These services publish no registration endpoint, so there is nothing to register with. Claude Code's MCP guide says this error means "the server requires pre-configured credentials".

Fix (Claude Code 2.1.30 or later; 2.1.231 or later if the provider checks the redirect address exactly):

1. Register an OAuth app in the provider's developer portal. If it asks for a redirect URI, enter http://localhost:PORT/callback with a free port, for example 8080.

2. Add the server with that app's id. --client-secret asks for the secret with hidden input; leave it out for a public client that has no secret:

   claude mcp add --transport http \
     --client-id <your-client-id> --client-secret --callback-port 8080 \
     <name> <server-url>
   

   With add-json, put "oauth": {"clientId": "...", "callbackPort": 8080} in the JSON and pass --client-secret as a flag.

3. Run /mcp and finish the sign-in in the browser. claude mcp get <name> shows whether the credentials are set.

Notes:

• The secret can only be set when the server is added. To change it, claude mcp remove <name> and add it again with the same --scope.
• These flags apply to HTTP and SSE servers only, not stdio.
• On 2.1.229 the redirect was sent as http://127.0.0.1:PORT/callback and exact-match providers refused it; 2.1.231 restored localhost.
• Servers that publish a Client ID Metadata Document are handled automatically from 2.1.81.

Versions: pre-configured credentials added in 2.1.30; Client ID Metadata Documents in 2.1.81; redirect fix in 2.1.231. Current release on 28 Oct 2026: 2.1.312.

Sources:

• Claude Code MCP guide, "Use pre-configured OAuth credentials": https://code.claude.com/docs/en/mcp
• Claude Code changelog (2.1.30, 2.1.81, 2.1.231): https://github.com/anthropics/claude-code/blob/main/CHANGELOG.md
• Maintainer's closing comment naming both fixes: https://github.com/anthropics/claude-code/issues/18009
• A reporter confirming the steps against GitHub's server on 2.1.206: https://github.com/anthropics/claude-code/issues/67258

Verified: the error text, the cause, the flags and the versions, against Anthropic's guide, changelog and a maintainer's comment (28 Oct 2026). Not verified: not run here, since it needs an OAuth app with a provider. One reporter on 2.1.172 (Box, AWS Cognito) still saw the error with a client id set; that issue closed as stale without a fix named.