Eric Allam
9ff410bfa4
## Summary
Type `chat.createStartSessionAction` against the chat agent so
`clientData` is typed end-to-end on the first turn. Closes the gap where
`useTriggerChatTransport`'s `startSession` callback already hands you a
typed `clientData` (via the transport generic) but the server-side
action couldn't accept it without untyped routing through the `metadata`
field.
## Design
`ChatStartSessionParams` gains a typed `clientData` field via the new
generic:
```ts
export type ChatStartSessionParams<TChat extends AnyTask = AnyTask> = {
chatId: string;
clientData?: InferChatClientData<TChat>;
triggerConfig?: Partial<SessionTriggerConfig>;
metadata?: Record<string, unknown>;
};
function createChatStartSessionAction<TChat extends AnyTask = AnyTask>(
taskId: string,
options?: CreateChatStartSessionActionOptions
): (params: ChatStartSessionParams<TChat>) => Promise<ChatStartSessionResult>
```
When provided, `clientData` is folded into the first run's
`triggerConfig.basePayload.metadata`, so `onPreload` / `onChatStart` see
the same shape per-turn `metadata` carries via the transport. The opaque
session-level `metadata` field stays exactly as before — it lands on the
Session row, not the run payload.
## Usage
```ts
// actions.ts
import { chat } from "@trigger.dev/sdk/ai";
import type { myChat } from "@/trigger/chat";
export const startChatSession = chat.createStartSessionAction<typeof myChat>("my-chat");
```
```tsx
// Chat.tsx
const transport = useTriggerChatTransport<typeof myChat>({
task: "my-chat",
accessToken: ({ chatId }) => mintChatAccessToken(chatId),
startSession: ({ chatId, clientData }) =>
startChatSession({ chatId, clientData }),
});
```
## Test plan
- [x] `pnpm run build --filter @trigger.dev/sdk` passes
- [ ] Verify a `chat.agent` with `clientDataSchema` reads the typed
clientData from `onPreload` payload metadata on the first turn
Official TypeScript SDK for Trigger.dev
The Trigger.dev SDK is a TypeScript/JavaScript library that allows you to define and trigger tasks in your projects.
About Trigger.dev
Trigger.dev is an open source platform for building and deploying fully-managed AI agents and workflows. Write workflows in normal async TypeScript for everything from simple tasks to long-running AI agents, heavy media processing, complex real-time systems and more. Complete with full observability, managed queues, and elastic infrastructure which handles the horizontal scaling.
Core features
- Task creation and execution
- CLI for development and deployment
- Build system with extensions
- Management API for runs, schedules, and environment variables
Key Components:
- Tasks: Background jobs written in TypeScript/JavaScript
- CLI: Commands for login, init, dev, deploy
- Build Extensions: Customize builds (Prisma, Python, FFmpeg, etc.)
- Management API: Programmatic control over runs and resources
Getting started
There are two ways to get started:
- Create an account in our web app, create a new project and follow the instructions in the onboarding. Build and deploy your first task in minutes.
- Manual setup in your existing project.
SDK documentation
For more information on our SDK, refer to our docs.
Support
If you have any questions, please reach out to us on Discord and we'll be happy to help.