Skip to content

HTTP MCP server with Bearer token fails OAuth discovery instead of falling back to headers auth #3100

@vladk2854-max

Description

@vladk2854-max

Describe the bug

When an HTTP MCP server is configured in .mcp.json with "type": "http" and "headers": { "Authorization": "Bearer " }, the CLI attempts OAuth discovery
(/.well-known/oauth-authorization-server
) and fails with:

MCPOAuthError: Failed to discover authorization server metadata

The CLI does not fall back to using the provided Bearer token from headers, causing a hard auth failure even though valid credentials are present in the config.

Affected version

No response

Steps to reproduce the behavior

  1. Configure the mcp config for server which using custom token authorization
  2. Run /mcp
  3. Select the configured server
  4. Pay attention to the error

Actual behavior: Hard fail on OAuth discovery, server stays disabled.

Image

Expected behavior

Expected behavior: If OAuth discovery fails and headers contains Authorization: Bearer, the CLI should skip OAuth and proceed to MCP initialize using the provided token.

Additional context

Workaround: Manually enabling the server via /mcp enable bypasses OAuth discovery and connects successfully using the Bearer token.

MCP spec reference: OAuth is optional — clients should fall back to configured credentials when authorization server metadata is not found.

Metadata

Metadata

Assignees

No one assigned

    Labels

    area:authenticationLogin, OAuth, device auth, token management, and keychain integrationarea:mcpMCP server configuration, discovery, connectivity, OAuth, policy, and registry

    Type

    No fields configured for Bug.

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions