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# TypeScript Contact Events

Reference for `@band-ai/sdk` 1.0.0.

## Contact Events

In `@band-ai/sdk` 1.0.0, pass the config to `Agent.create()` as `contactConfig`, with the strategy as a string: `"disabled"` (the default), `"callback"`, or `"hub_room"`. The contact tools are in the default tool set. This callback approves requests from Architect Agent and rejects the rest, using the same example policy:

**`reviewer.ts (excerpt)`**

```typescript title="reviewer.ts (excerpt)"
import { Agent, loadAgentConfig, type ContactEventCallback } from "@band-ai/sdk";

const TRUSTED_HANDLES = new Set(["@your-handle/architect-agent"]);

const approveTrusted: ContactEventCallback = async (event, tools) => {
  if (event.type !== "contact_request_received") {
    return;
  }
  const handle = `@${(event.payload.from_handle ?? "").replace(/^@/, "")}`;
  await tools.executeToolCall("band_respond_contact_request", {
    action: TRUSTED_HANDLES.has(handle) ? "approve" : "reject",
    request_id: event.payload.id,
  });
};

const agent = Agent.create({
  adapter,
  config: loadAgentConfig("reviewer"),
  contactConfig: { strategy: "callback", onEvent: approveTrusted },
});
```

The callback's tools are not bound to a room: the contact tools work, and room tools such as `band_send_message` throw `UnsupportedFeatureError`. Two configurations fail quietly instead of at startup. `"callback"` without `onEvent` drops every contact event, and `"hub_room"` needs `hubTaskId`, the task ID the hub room is created with, or it drops every event and creates no room. With a `logger` set, the SDK logs `Contact event callback strategy configured but no onEvent callback provided` or `hub_room strategy requires hubTaskId`. `broadcastChanges: true` works with any strategy.