Fixes#36767.
Two complementary recoveries for the recurring "delete three cache files and
re-auth by hand" ritual when an MCP server's dynamically-registered OAuth
client goes dead server-side (IdP redeploy / DB wipe / rebrand):
- Auto-heal (token-endpoint subset): HermesMCPOAuthProvider now sniffs
auth-flow responses and, on a 400/401 `invalid_client` from the discovered
token endpoint, backs up + deletes `<server>.client.json` and `.meta.json`
and clears the in-memory client so the SDK re-runs RFC 7591 dynamic client
registration on the next flow. Conservative by construction: only
dynamically-registered (non config-supplied) clients, only the token
endpoint, only on a word-boundary `invalid_client` match (so RFC 7591's
`invalid_client_metadata` does not trip it); best-effort so a miss never
breaks the live flow. Covers both code-exchange and refresh when the token
endpoint was discovered. Tokens are preserved.
- `hermes mcp reauth [<name>|--all]`: the reporter's primary symptom — the
IdP's in-browser "Redirect URI Mismatch" — produces no HTTP signal (the SDK
only sees a callback timeout), so it cannot be auto-detected. The new
command re-auths one or ALL `auth: oauth` servers, serially: one browser
flow at a time, which also fixes the startup popup storm when several
servers are stale at once. Single-server reauth is factored out of
`mcp login` and shared.
Tests: +14 (poison helper x2; token-endpoint detection x5 incl. wrong-endpoint,
success-response, pre-registered, and invalid_client_metadata negative guards;
a bridge integration test driving the real async_auth_flow generator to prove
the detection hook preserves the bidirectional asend() forwarding contract;
reauth CLI x6). Verified against the pinned mcp==1.26.0: scripts/run_tests.sh
122/122 green for the touched suites; check-windows-footguns.py and ruff clean.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>