OAuth 2.1 makeover: PKCE-only, hashed tokens, real consent with scoped permissions - #68
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…h scoped permissions Replaces the secret-based OAuth connector flow with a spec-compliant OAuth 2.1 authorization server for MCP clients: - Discovery metadata (RFC 8414/9728) + dynamic client registration (RFC 7591): clients need only the MCP URL, no credentials to copy - Public clients with mandatory PKCE S256; client secrets removed - Auth codes, access tokens, and refresh tokens stored as SHA-256 digests only; 1h access tokens with rotating single-use refresh tokens (was: 90-day static tokens stored verbatim) - Consent page lists each requested privilege as a user-toggleable checkbox with a Deny option; tokens carry exactly what was approved - Strict scopes: no default-to-full-access, no claudeai escalation, static API-key fallback removed - 401s advertise resource metadata via WWW-Authenticate so MCP clients bootstrap the flow automatically - Flutter: Connected Apps screen (grants + revoke) replaces the client-secret / static-token copy screen - Firestore rules lock OAuth collections to Cloud Functions; users can read their own grant records - functions/test-oauth-flow.mjs: 36-check emulator e2e of the full flow (discovery → register → consent → PKCE exchange → scoped MCP calls → refresh rotation → revocation) Breaking: existing static API keys and legacy plaintext tokens no longer authenticate; users reconnect via the OAuth flow. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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The deploy workflow only shipped hosting and functions, so rules changes (like the OAuth 2.1 lockdown in #68) never reached prod. firebase deploy --only firestore covers rules + indexes per firebase.json. Co-authored-by: Nick Stoddart <nickstoddart@Nicks-MacBook-Pro.local> Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
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Summary
Replaces the secret-based OAuth connector flow with a spec-compliant OAuth 2.1 authorization server for MCP clients (Claude.ai / Claude Desktop):
claudeaiscope escalation; every MCP tool enforces its scopeWWW-Authenticateon 401 — users paste only the MCP URLBreaking change
Existing static API keys and legacy plaintext OAuth tokens no longer authenticate. Users reconnect once via the new flow. Deploy needs both
--only functionsand--only firestore:rules.Test plan
functions/test-oauth-flow.mjs: 36-check emulator e2e — discovery, registration, consent page content, PKCE enforcement (missing/wrong verifier), single-use codes, scoped token issuance, hashed-at-rest verification, real MCP client connection with scope enforcement, refresh rotation + replay rejection, grant revocation killing live tokens (all passing)flutter analyzeclean on changed filestscbuild clean🤖 Generated with Claude Code