Provider integrations overview

Scope

This domain documents f3router's provider layer: the platforms the gateway aggregates, how each is authenticated and adapted, and how per-key quota accounting, cooldowns, and health checks keep free tiers usable behind one OpenAI-compatible API.

The authoritative sources are shared/types.ts (the Platform union), server/src/providers/index.ts (the runtime registry), and server/src/providers/base.ts (the adapter contract). The public catalog headline — roughly 34 free providers, 474 model families, 635 free endpoints (~7.4 billion tokens/month of listed capacity) — comes from the provider table in the README; the catalog itself tracks fewer platforms than the type union declares because some union members are retired or user-defined rather than catalog-managed.

File index

File	Description
01-supported-platforms.md	One row per platform declared in `shared/types.ts`: auth model (keyed/keyless), adapter class (native/OpenAI-compatible), and integration notes. Explicit counts for every grouping.
02-quotas-and-cooldowns.md	RPM/RPD and TPM/TPD window accounting, concurrency leases and opt-in caps, the cooldown ladder and its provenance classes, probe-based early recovery, back-off parsed from `Retry-After` headers and error bodies (#798), and why health checks must not burn metered quota (#882).
03-adding-a-new-provider.md	Contributor walkthrough: extending the `Platform` union, choosing an adapter, registration options (timeouts, keyless, extra headers), key-validation semantics, catalog seeding policy, and the tests a new provider is expected to ship.
04-recurring-credit-gateways.md	ElectronHub and Experiential Labs: shared credits, key validation, adapter behavior, and billing limits.

Conventions

Adapters live in server/src/providers/; every platform registered there appears on /v1 routing immediately — no separate enable step.
Model rows are seeded two ways: versioned migrations for launch-time rosters, and the signed hosted catalog (services/catalog-sync.ts, gated on hasProvider) for everything catalog-managed afterwards.
Quota limits are data, not code: rpm_limit / rpd_limit / tpm_limit / tpd_limit columns on each catalog model row drive pre-throttling; see 02-quotas-and-cooldowns.md.