- Added `checkCredentials()` with result types/options for per-credential tri-state health checks.
- Added `/v1/credentials/check` endpoint via `handleCredentialsCheck` returning `{ generatedAt, credentials }`.
- Added `omp auth-gateway check` flow with provider grouping, `--json` output, and exit status 1 on failures.
- Added command examples, changelog updates, and tests for expired OAuth refresh, null/missing config, and ordering edge cases.
- Added generation-aware snapshot contracts with generation, serverNowMs, refresher, and rotatesInMs fields.
- Reworked /v1/snapshot serving and client fetching for If-None-Match long-poll with 304/200 status handling.
- Added status checks in remote-store and SDK/CLI snapshot paths, applying updates only when fetch returns 200.
- Added StreamOptions.onAuthError and stream one-shot 401 retry dispatch using refreshed credentials.
- Added `omp auth-gateway serve/token/status` — a forward-proxy injecting broker credentials for OpenAI Chat, Anthropic Messages, and OpenAI Responses wire formats.
- Added `GET /v1/usage` to auth-broker and auth-gateway; usage cache switched to 5-min per-credential TTL with jitter and last-good fallback on failure.
- Added `AuthStorage.setConfigApiKey/removeConfigApiKey/clearConfigApiKeys` so `models.yml` `apiKey` beats OAuth tokens without overriding `--api-key`.
- Added `omp auth-broker migrate --from-local` for idempotent upload of local SQLite/env credentials to the broker.