> ## Documentation Index > Fetch the complete documentation index at: https://docs.agno.com/llms.txt > Use this file to discover all available pages before exploring further. # Slack Reference > Interface parameters, endpoints, event handling, and OAuth scopes for the Slack interface. ## Interface Parameters Pass one of `agent`, `team`, or `workflow` to the `Slack` constructor. ```python theme={null} from agno.os.interfaces.slack import Slack Slack(agent=my_agent, streaming=True, prefix="/slack") ``` | Parameter | Type | Default | Description | | ------------------------ | -------------------------------- | --------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `agent` | `Optional[Agent]` | `None` | Agno `Agent` instance. | | `team` | `Optional[Team]` | `None` | Agno `Team` instance. | | `workflow` | `Optional[Workflow]` | `None` | Agno `Workflow` instance. | | `prefix` | `str` | `"/slack"` | URL prefix for Slack endpoints (e.g., `/slack` means events arrive at `/slack/events`). | | `tags` | `Optional[List[str]]` | `None` | FastAPI route tags for API documentation. Defaults to `["Slack"]`. | | `reply_to_mentions_only` | `bool` | `True` | When `True` (default), the bot responds to @mentions in channels and all DMs. When `False`, responds to all channel messages. | | `token` | `Optional[str]` | `None` | Bot token. Falls back to `SLACK_TOKEN` environment variable. | | `signing_secret` | `Optional[str]` | `None` | Slack app signing secret. Falls back to `SLACK_SIGNING_SECRET` environment variable. | | `streaming` | `bool` | `True` | Enable real-time streaming with task cards and live text updates. | | `loading_messages` | `Optional[List[str]]` | `None` | Status messages shown while the agent processes. Rotated automatically by Slack. | | `task_display_mode` | `str` | `"plan"` | How task cards render in the streaming UI. `"plan"` shows a collapsible plan block. | | `loading_text` | `str` | `"Thinking..."` | Status text shown while the agent starts processing. | | `suggested_prompts` | `Optional[List[Dict[str, str]]]` | `None` | Prompts shown when a user opens a new thread. Each dict has `title` and `message` keys. Defaults to Help and Search prompts. | | `ssl` | `Optional[SSLContext]` | `None` | SSL context for the Slack WebClient. | | `buffer_size` | `int` | `100` | Characters to buffer before flushing a streaming update. | | `max_file_size` | `int` | `1073741824` | Maximum file size in bytes for uploads and downloads (default 1 GB). | | `resolve_user_identity` | `bool` | `False` | Look up each user's email and display name via the Slack `users.info` API. When enabled, the agent receives the user's email as `user_id` instead of their Slack ID, and `metadata` includes `user_name` and `user_email`. | ## Endpoints Available at the `/slack` prefix (customizable with `prefix`). ### `POST {prefix}/events` Receives all Slack events (URL verification, messages, app mentions, thread starts). | Status | Description | | ------- | --------------------------------------------------------------------------------------------------- | | **200** | Event acknowledged. Processing happens in the background so Slack gets a response within 3 seconds. | | **400** | Missing `X-Slack-Request-Timestamp` or `X-Slack-Signature` headers. | | **403** | Invalid Slack signing signature. | | **500** | `SLACK_SIGNING_SECRET` is not set (checked on each request, not at startup). | ### Built-in Event Handling | Event | Behavior | | -------------------------- | --------------------------------------------------------------------------------------------------------------------------------------- | | URL verification | Echoes the `challenge` field back to Slack during app setup. | | `assistant_thread_started` | Sets `suggested_prompts` on new threads (streaming mode only). | | Retry deduplication | Events with `X-Slack-Retry-Num` are acknowledged without reprocessing. The original event is already being processed in the background. | | Bot self-loop prevention | Events with `bot_id` or subtypes `bot_message`, `message_changed`, `message_deleted`, and other bot lifecycle events are ignored. | ## OAuth Scopes Add scopes in your Slack App under **OAuth & Permissions > Bot Token Scopes**. ### Minimum (streaming bot) | Scope | Required For | | ------------------- | ------------------------------------------------------ | | `app_mentions:read` | Receive @mention events in channels | | `assistant:write` | Streaming task cards, suggested prompts, thread titles | | `channels:read` | Resolve channel names (called on every inbound event) | | `chat:write` | Send messages and stream responses | | `im:history` | Read DM history for thread context | ### File Handling | Scope | Required For | | ------------- | --------------------------------------------------------------- | | `files:read` | Download files users attach to messages | | `files:write` | Upload images, audio, video, and files generated by agent tools | ### SlackTools Methods | Scope | Required For | | -------------------- | ----------------------------------------------------------- | | `channels:read` | `list_channels()`, `get_channel_info()` | | `channels:history` | `get_channel_history()`, `get_thread()` in public channels | | `groups:read` | `list_channels()` for private channels | | `groups:history` | `get_channel_history()`, `get_thread()` in private channels | | `search:read` | `search_messages()` (requires user token) | | `search:read.public` | `search_workspace()` messages and channels | | `search:read.files` | `search_workspace()` files | | `search:read.users` | `search_workspace()` users | | `users:read` | `list_users()`, `get_user_info()` | | `users:read.email` | `get_user_info()` with email field | ### Feature-Specific | Scope | Required For | | ------------------ | --------------------------------------------------- | | `users:read` | `resolve_user_identity=True` on the Slack interface | | `users:read.email` | `resolve_user_identity=True` with email lookup | | `channels:history` | `reply_to_mentions_only=False` in public channels | | `groups:history` | `reply_to_mentions_only=False` in private channels | ## Event Subscriptions Subscribe to events under **Event Subscriptions > Subscribe to bot events**. | Event | Required For | | -------------------------- | ------------------------------------------------------------------------ | | `app_mention` | Respond to @mentions in channels | | `message.im` | Respond to direct messages | | `assistant_thread_started` | Set suggested prompts on new threads | | `message.channels` | Respond to all public channel messages (`reply_to_mentions_only=False`) | | `message.groups` | Respond to all private channel messages (`reply_to_mentions_only=False`) | ## Developer Resources Sessions, threads, files, streaming, and troubleshooting. Create a Slack App and configure step by step. Toolkit methods for messaging, search, and files.