Slack

Connect OpenCrabs to Slack workspaces.

Setup

Step 1: Create a Slack App

1. Go to api.slack.com/apps
2. Create a new app (From Scratch)
3. Enable Socket Mode under Settings
4. Generate an App-Level Token (Settings → Basic Information → App-Level Tokens) with connections:write scope
5. Under OAuth & Permissions, add bot scopes: chat:write, channels:history, groups:history, im:history, reactions:write
6. Install the app to your workspace
7. Copy the Bot Token (xoxb-...) and App-Level Token (xapp-...)

Step 2: Configure via the Onboarding Wizard

Run /onboard:channels (or /onboard and navigate to the Channels step):

1. Use ↑/↓ to focus Slack
2. Press Space to toggle it on
3. Press Enter to open the Slack setup screen
4. Fill in the fields:
   • Bot Token — the xoxb-... token
   • App Token — the xapp-... token
   • Channel ID — right-click a channel → View channel details → copy the Channel ID at the bottom
   • Allowed Users — comma-separated Slack user IDs (Profile → ⋯ → Copy member ID)
   • Respond To — all, dm_only, or mention
5. Press Enter on Test Connection to verify
6. Press Enter to save

Manual Configuration (advanced)

# keys.toml
[channels.slack]
bot_token = "xoxb-..."
app_token = "xapp-..."

# config.toml
[channels.slack]
enabled = true
allowed_channels = ["C12345678"]
allowed_users = []
respond_to = "all"

Configuration

All Slack options live under [channels.slack] in ~/.opencrabs/config.toml:

[channels.slack]
enabled = true
token = "xoxb-your-bot-token"          # or store in keys.toml
app_token = "xapp-your-app-token"      # Socket Mode token
allowed_users = ["U12345678"]           # Slack user IDs
allowed_channels = ["C12345678"]
respond_to = "mention"                  # "all", "dm_only", "mention" (default)
session_idle_hours = 24.0               # idle timeout for non-owner sessions

Features

• Channels and DMs — Works in public/private channels and direct messages
• Action buttons — Provider picker, model picker, session switcher use Slack action buttons
• Thread support — Responds in threads when appropriate
• Slash commands — All built-in and custom commands work
• Reactions — Agent can add emoji reactions. Emoji reactions from users trigger agent turns (react-back)
• Grouped tool calls — Consecutive tool calls collapse into one edited-in-place message with Expand/Collapse toggle
• TTS voice replies — Voice responses sent as OGG/Opus files via files.upload with inline waveform UI

Grouped Tool Calls (v0.3.62)

Consecutive tool calls collapse into a single message in Slack. The message is edited in-place as each tool executes. Users can toggle between expanded and collapsed views with an Expand/Collapse button. This keeps channels clean during multi-step operations.

Reactions (v0.3.62)

The agent can add emoji reactions to messages. When a user reacts with an emoji, it triggers an agent turn (react-back). This enables quick, lightweight interactions without typing full messages. Parity with Telegram and Discord.

Reactions (v0.3.62)

Slack supports emoji reactions for lightweight acknowledgements:

• React-back: When you react to a bot message, the bot acknowledges it (e.g., adds a 👍 to show it saw your reaction)
• Reaction turns: Certain reactions can trigger agent actions (configurable)
• Grouped tool calls: Multiple tool calls in one turn collapse into a single collapsible message, keeping the channel clean

Socket Mode

Slack uses Socket Mode (WebSocket) instead of HTTP webhooks — no public URL or ngrok needed. The connection is outbound from your machine.