Setup
Connect Slack from your Integrations settings.Connect your workspace
Click Connect Slack in the Slack integration card. You’ll be redirected to Slack to authorize the Cyrus bot for your workspace.
Grant permissions
Approve the requested bot permissions. These allow Cyrus to receive
@mentions, read channel context, and reply with messages.After connecting, you may need to invite the Cyrus bot to specific channels before it can receive mentions there. Use
/invite @Cyrus in any channel where you want to interact with the agent.@mention Triggers
Mention the Cyrus bot in a Slack channel or thread to start a session. Cyrus will:- Receive the mention event via webhook
- Validate your team’s subscription and plan
- Start an agent session with the message as context
- Reply in a thread on the original message
Thread Context
When you mention Cyrus in a thread, the agent session includes the full thread history as context. This means:- Other participants’ messages are visible to Cyrus
- Messages from other bots (Sentry alerts, CI notifications, GitHub updates) are preserved in context
- Follow-up mentions in the same thread continue the same session, so Cyrus remembers prior conversation
When to Use Slack vs Linear
Slack sessions and Linear sessions serve different purposes:| Slack Sessions | Linear Sessions | |
|---|---|---|
| Environment | Runs in a temporary empty directory — no repository checkout | Runs in an isolated Git worktree with full repo access |
| Best for | Quick questions, research, brainstorming, searching docs, Slack workspace queries | Code changes, bug fixes, feature implementation, pull requests |
| Output | Conversational replies in Slack threads | Commits, branches, and pull requests on GitHub |
Slack sessions do not create Git worktrees or have access to your codebase. For any work that involves reading or modifying code, create a Linear issue and assign it to Cyrus instead.
Slack MCP Tools
When the Slack integration is connected, Cyrus automatically gains access to Slack MCP tools during agent sessions. These tools let Cyrus:- Read channels — browse message history in channels the bot has access to
- Search messages — find relevant messages and files across the workspace
- Look up users — resolve user information and email addresses
How It Works
Under the hood, the integration uses Slack’s Events API and OAuth 2.0:| Component | Description |
|---|---|
| OAuth | Bot token is securely stored and encrypted at rest |
| Webhooks | app_mention events are verified using HMAC-SHA256 signature verification |
| Forwarding | Verified events are routed to your Cyrus instance for processing |
| Responses | Cyrus replies using Slack’s native mrkdwn formatting for proper rendering |
Disconnecting
To disconnect Slack:- Go to Integrations settings
- Click the dropdown on the Slack integration card
- Select Disconnect Slack
Troubleshooting
Cyrus doesn’t respond to my mention- Make sure the Cyrus bot has been invited to the channel (use
/invite @Cyrus) - Verify the Slack integration shows as connected in Integrations settings
- Confirm your team has an active subscription
- Cyrus uses Slack’s native
mrkdwnsyntax. If formatting looks off, it may be a rendering issue in an older Slack client — try updating Slack
- If Cyrus stops responding after reconnecting, try disconnecting and connecting again from the Integrations settings page
- The bot token is synced to your infrastructure automatically during connection
Cyrus Community
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