## Description
Registers `/api/v2/ai-gateway/*` as the new API path for AI Gateway, replacing `/api/v2/aibridge/*`. Both prefixes share the same route builder (`aiBridgeRoutes`) backed by a single in-memory handler, so existing `/aibridge` endpoints continue to work. New endpoints must be registered on the enterprise API handler under `/api/v2/ai-gateway` only.
Swagger annotations now point to `/api/v2/ai-gateway` paths with a backward-compatibility note referencing `/aibridge`. The legacy `/aibridge` routes are skipped in the swagger documentation test.
## Changes
- Store one raw handler (`aiGatewayHandler`) instead of two prefix-stripped handlers
- Register `/ai-gateway` and `/ai-gateway/proxy` route aliases alongside legacy `/aibridge` routes
- Move `/aibridge/keys` to `/ai-gateway/keys`
- Update in-process transport to use `/api/v2/ai-gateway` prefix
- Update SDK client URLs and proxy forwarding URL
- Swap `@Router` and `@Tags` annotations from `aibridge`/`AI Bridge` to `ai-gateway`/`AI Gateway`
- Rename user-facing error messages from "AI Bridge" to "AI Gateway"
- Define consts for route prefixes (`AIGatewayRootPath`, `AIBridgeRootPath`)
- Update tests and comments to use new paths
Note: the following will be addressed in follow-up PRs:
- Frontend API URLs
- Frontend routes and redirects
- Dogfood main.tf updates
- Hand-written documentation URL updates
- aibridge internal comments and nits
- Scale tests path updates
Refs https://linear.app/coder/issue/AIGOV-230
> Generated with the assistance of Coder Agents (@ssncferreira)
Allows an `api_key_id` to be passed from a trusted in-memory transport
(currently: `chatd`) to `aibridged` for use in authenticating LLM
requests.
This value can _only_ be passed via context, and all users of the
in-memory transport _must_ provide it.
It can be used in conjunction with BYOK headers.
---------
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
### TL;DR
Introduces an in-process `TransportFactory` for aibridge so that chatd (coder-agent LLM traffic) can route requests through the aibridged handler without crossing the HTTP route or requiring a license entitlement check.
### What changed?
- Added a new `coderd/aibridge` package with a `TransportFactory` interface and a `Source` type for tagging the call site on request contexts. `SourceAgents` is defined as the constant for coder-agent traffic.
- Implemented `NewTransportFactory` in `coderd/aibridged/transport.go`, which returns an `http.RoundTripper` that dispatches requests to the aibridged handler in-process. The response body is streamed through an `io.Pipe` so SSE/NDJSON/chunked responses propagate token-by-token. Handler panics are recovered and surfaced as 500 responses, and context cancellation closes the pipe with the appropriate error.
- `RegisterInMemoryAIBridgedHTTPHandler` now also constructs a `TransportFactory` from the registered handler and stores it on `API.AIBridgeTransportFactory` (an `atomic.Pointer`), making it available to chatd without going through the license-gated HTTP route.
- Added `API.AIBridgeTransportFactory` as a public `atomic.Pointer[aibridge.TransportFactory]` field on `coderd.API`.
### How to test?
- `coderd/aibridged/transport_test.go` covers: transport creation, nil-handler errors, source attachment to context, header/status passthrough, streaming (SSE-style chunked writes visible before handler completion), context cancellation closing the body with an error, concurrent requests, handler panics producing 500s, and handlers that return without writing.
- `coderd/aibridge_test.go` verifies that `AIBridgeTransportFactory` starts as nil on AGPL coderd, can be stored and loaded atomically, and that the stored factory correctly dispatches requests through the stub handler.
### Why make this change?
Chatd needs to send LLM requests through aibridge in-process rather than via the external HTTP route, which is license-gated. The `TransportFactory` abstraction provides a clean seam: the entitlement check remains on the HTTP route for external callers, while in-process coder-agent traffic bypasses it through the factory. The `Source` type allows downstream handlers and logs to attribute traffic without gating behavior on the caller identity.
Susana Ferreira