docs(mcp-oauth): document oauth2_flow as required for oauth2 MCP servers - #505

What

Updates every auth_type: oauth2 MCP server config example to include the now-required oauth2_flow field, and corrects the config reference to match current behavior.

Since BerriAI/litellm#32292, an auth_type: oauth2 server in config.yaml must declare oauth2_flow: client_credentials (M2M) or oauth2_flow: authorization_code (interactive PKCE, including delegate_auth_to_upstream). The proxy raises a ValueError at startup when the field is missing or invalid, and no longer infers the flow from field shape for config entries. Only legacy DB rows created before the field existed still fall back to shape inference at request time.

Without this change, every oauth2 config example in the docs fails proxy startup on current builds.

Resolves LIT-4251

Changes

docs/mcp_oauth.md: adds an oauth2_flow column to the flow comparison table so the interactive flow visibly maps to authorization_code; adds the field to the interactive setup, M2M setup, mock-server test config, and delegate-auth examples; rewrites the oauth2_flow config reference row from optional-with-inference to required; adds the field to the delegate section's config reference.

docs/mcp_control.md, docs/tutorials/claude_mcp.md, docs/mcp.md: adds oauth2_flow to the remaining oauth2 examples (authorization_code for all; they are interactive GitHub/Atlassian setups) and a sentence in mcp.md stating the flow must be declared.

Screenshots

Each pair below renders the affected doc section from a local Docusaurus build, main on the left and this branch on the right.

docs/mcp_oauth.md

The flow comparison table gains an oauth2_flow column so each flow visibly maps to its config value.

The config reference row for oauth2_flow moves from optional with shape inference to required, and states that the proxy refuses to start when it is missing.

The interactive PKCE and machine-to-machine setup examples now declare the flow explicitly.

The delegate-auth example and its config reference add oauth2_flow: authorization_code, since delegated servers are interactive.

docs/mcp.md, docs/mcp_control.md, docs/tutorials/claude_mcp.md

The remaining oauth2 examples across these pages pick up the field, and the mcp.md overview adds a sentence explaining that the flow must be declared.

Note on timing

This documents the behavior on litellm_internal_staging (required-in-config landed 2026-07-07). If the docs site should track the latest stable release, hold merging until that change ships; the examples themselves are forward-compatible either way since the field is accepted on older versions that still infer.

🤖 Generated with Claude Code

Link to Devin session: https://app.devin.ai/sessions/f03da2725ec94d28b3facf766871b102