chat.agent now runs on top of the Session-as-run-manager primitive.
Public surface (`chat.agent({...})`, `useTriggerChatTransport`,
`chat.store` / `chat.defer` / `chat.history`, `AgentChat`) is unchanged;
the wiring underneath moves from per-run streams to the durable Session
row that owns its own runs.
Transport (TriggerChatTransport):
- Drop `getStartToken`. Replace with
`startSession({chatId, taskId, clientData}) => {publicAccessToken}` —
wraps a server action that calls `chat.createStartSessionAction`.
Idempotent on `(env, externalId)`.
- `clientData` (typed via `withClientData`) is threaded through
`startSession`'s params, so the first run's `basePayload.metadata`
matches per-turn `metadata`. Live-updated via `setClientData` when
the hook's `clientData` option changes.
- Drop transport-level `triggerConfig` / `triggerOptions` /
`idleTimeoutInSeconds`. All trigger config lives server-side in the
customer's `chat.createStartSessionAction(taskId, options)`.
- `transport.preload(chatId)` and lazy first `sendMessage` both route
through `startSession`, deduped via the in-flight pendingStarts map.
- `ChatSession` persistable shape drops `runId`; just `{lastEventId}`.
chat.agent runtime:
- New `chat.createStartSessionAction(taskId, options?)` — server-side
wrapper that calls `sessions.start` with `basePayload.{messages:[],
trigger: "preload"}` defaults plus the customer's overrides. Returns
`{sessionId, runId, publicAccessToken}`.
- `chat.requestUpgrade` calls `apiClient.endAndContinueSession` before
emitting the `trigger:upgrade-required` chunk. Server orchestrates
the swap; browser keeps streaming across the run handoff.
Webapp dashboard:
- Playground: `startSession` + `accessToken` both wired through the
Remix action (idempotent server-side start path). Preload button
now works. New session proxy routes for HEAD/GET on `/out` and POST
on `/in/append`; old run-stream proxies deleted.
- Run inspector Agent tab: SSE proxy now uses the canonical addressing
key (externalId if set, else friendlyId), matching what the agent
writes via `session.out`. Fixes the case where the Agent tab read
from a different S2 stream than the agent wrote to.
References (ai-chat):
- `chat-view` useEffect dance gone (just hydrates `initialSession`).
- `chat-app` `transport.preload(id)` routes through `startSession`.
- New `upgrade-test` agent + sidebar option for exercising
`chat.requestUpgrade` end-to-end.
- `ChatSession` schema simplified: drop `runId` / `sessionId`, keep
`publicAccessToken` + `lastEventId`.
- `chat-client-test` fixed for the new transport shape.
- Hello-world smoke stubs gutted to TODO placeholders — sessions
are now task-bound, so standalone-session smokes need rewriting.
Eric Allam
37503a4f43