- Broker op VerifySlackSignature: v0 HMAC-SHA256 computed INSIDE the broker
(constant-time compare); the signing secret never crosses the socket.
Slack secrets are one JSON credential {bot_token, signing_secret}; the
broker extracts the right field per operation
- Public POST /api/slack/events: signature verified against connected slack
connections via the broker; forged signatures 401; url_verification
handshake echoed only when signed; app_mention starts a real run in the
agent's dedicated '💬 Slack' session — and the agent's reply is itself a
gated outbound post
- SlackApp Connection tab captures bot token + signing secret
- Integration test: forged 401, signed challenge, signed mention -> run ->
slack.post pending in the approval queue
- E2E: full loop — connect, gated outbound (sink empty -> exactly one post),
then a node-crypto-signed mention -> approval card -> approve -> 'On it!'
lands in the sink
134 Rust + 63 frontend tests + 21 Playwright journeys.
Co-Authored-By: Claude Fable 5 <[email protected]>