Slack Notifications

MCP Server

Package: @kazuph/mcp-slack (stdio). Auth: SLACK_MCP_XOXB_TOKEN env var. Enable SLACK_MCP_ADD_MESSAGE_TOOL=true.

See REFERENCE.md for OAuth scopes and token setup.

Agent Notification Patterns

Progress Updates

🔄 TAS-42 — In progress — implementing unit tests
Files: 3 (PriceFilter.tsx, test, index) | ETA: ~5 min

MCP invocation example

Post an approval request:

const res = mcp_slack_conversations_add_message({
  channel: 'C012345',
  text: '⏳ Approval Required — TAS-42: Run DB migration?',
  thread_ts: null
});
if (!res?.ok) throw new Error('Slack post failed: ' + res?.error);

Bi-Directional Communication

Approval requests are dual-channel — post to Slack AND ask in chat. First response wins.

1. Post to Slack:

   ⏳ Approval Required — TAS-42: Run DB migration
   Reply: ✅ approved | ❌ rejected | 💬 questions

2. Ask in chat with the same question.

3. Chat response wins → post confirmation to Slack thread.

4. Waiting for Slack → poll thread:

// Poll for approval reply (30s interval, 10 min timeout)
const replies = mcp_slack_conversations_replies({ channel: 'C012345', ts: threadTs, limit: 20 });
for (const msg of replies?.messages || []) {
  if (/\b(approved|yes|go)\b/i.test(msg.text)) return 'approved';
  if (/\b(rejected|no|stop)\b/i.test(msg.text)) return 'rejected';
}
// Retry after 30s; timeout after 10 min

5. If session ends before reply — Save to checkpoint with channel, thread ID, question, and timestamp. The next session's on-session-start hook checks for replies.

Conventions

Project-specific channel mappings: .opencastle/stack/notifications-config.md. Always thread replies; one thread per task; include tracker issue ID.

Rate Limits

Write: 20/min; Read: 50/min. Batch updates; use threads; cache channel/user IDs.

See REFERENCE.md for security guidelines.