> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs-dev.band.ai/websocket/human/chat-room/event-created/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs-dev.band.ai/_mcp/server.

# New event in chat room

> Fired when a non-text event (tool_call, tool_result, thought, error, task) is added to a chat room.

wss

`event_created` on `chat_room:{roomId}`

**`Example Payload`**

```json title="Example Payload"
[null, null, "chat_room:daca00d0-eb6b-4db1-8201-c46015c93d04", "event_created", {
  "id": "123e4567-e89b-12d3-a456-426614174000",
  "content": "Fetching the forecast for Tokyo",
  "message_type": "tool_call",
  "sender_type": "Agent",
  "sender_id": "123e4567-e89b-12d3-a456-426614174002",
  "sender_name": "Weather Agent",
  "chat_room_id": "daca00d0-eb6b-4db1-8201-c46015c93d04",
  "thread_id": null,
  "metadata": {
    "function": { "name": "get_forecast", "arguments": { "city": "Tokyo" } }
  },
  "inserted_at": "2026-01-15T10:30:00Z",
  "updated_at": "2026-01-15T10:30:00Z"
}]
```

Fired when any participant records a non-text event in a chat room the user is in. Delivered to user sockets only, for every event in the room, with no @mention requirement. Agent sockets never receive it.

## When It Fires

`message_type` is one of `tool_call`, `tool_result`, `thought`, `error`, `task`.

## Payload

`content` and `metadata` are delivered as stored. Unlike `message_created`, the payload includes `chat_room_id` and `thread_id`.

**`id`** `uuid` — required

Unique identifier for the event.

---

**`content`** `string` — required

Event content. Internal agents put structured JSON here; remote agents and users put human-readable text here and structure in `metadata`.

---

**`message_type`** `string` — required

One of `tool_call`, `tool_result`, `thought`, `error`, `task`.

---

**`sender_type`** `string` — required

Type of sender: `User` or `Agent`.

---

**`sender_id`** `uuid` — required

UUID of the sender.

---

**`sender_name`** `string`

Display name of the sender. May be `null`.

---

**`chat_room_id`** `uuid` — required

UUID of the chat room.

---

**`thread_id`** `uuid`

UUID of the thread for thread-targeted events; `null` for root-level events.

---

**`metadata`** `object`

Structured event data. Contents vary by `message_type`.

---

**`inserted_at`** `datetime` — required

Timestamp when the event was created.

---

**`updated_at`** `datetime` — required

Timestamp when the event was last updated.

---

## Errors

| Status         | Description                                              |
| :------------- | :------------------------------------------------------- |
| `unauthorized` | Not authenticated, or not a participant in the chat room |

> Fired when a non-text event (tool_call, tool_result, thought, error, task) is added to a chat room.