Slack Cloud Integration

The Slack cloud integration turns Aileron into a Slack agent. You can draft replies, ask questions, and write messages — all from within Slack. Always-on, no aileron launch required.

This is separate from the local Slack integration, which uses Socket Mode and requires an active terminal session. Both can coexist.

How it works

There are three ways to interact with Aileron in Slack:

Message shortcut

Hover over any message → click ⋯ → “Draft reply with Aileron”. A modal opens in your current channel with the AI-generated draft. Edit it, add refinement instructions, and click Send — the reply is posted as you.

Agent DM

Open the Aileron app in Slack and start a conversation. Aileron shows suggested prompts and streams responses in real time. You can iterate conversationally (“Make it shorter”, “Add context about the deadline”) and click Send when satisfied.

/aileron slash command

Type /aileron Draft me a weekly status update in any channel. A modal opens with the generated draft. Or ask a question — /aileron How many hours on calls today? — and get an ephemeral answer.

In all cases, replies are sent as you (via your user token), not as the bot.

Setup

Setup has two parts, performed by different people:

1. Install Aileron to your workspace — A workspace admin installs Aileron from the Slack App Directory. One click, done once per workspace.

2. Connect your Slack account — Each user connects their own Slack account to Aileron via OAuth. Takes under a minute.

Architecture

Slack workspace
    │
    ├── Message shortcut (⋯ → "Draft reply")
    ├── Agent DM (message.im)
    ├── /aileron slash command
    │
    ▼
Aileron Cloud
    │
    ├─ Verify HMAC-SHA256 signature
    ├─ Deduplicate by event_id
    ├─ Route by event type:
    │   ├─ assistant_thread_started → suggested prompts + title
    │   ├─ message.im → agent handler (streaming draft)
    │   ├─ message_action → open modal, generate draft
    │   └─ /aileron command → modal (draft) or ephemeral (question)
    │
    ▼
Draft Generation Pipeline
    │
    ├─ Round 1: Research — LLM gathers context via tools
    │   ├─ LLM may call tools (e.g. slack_channel_history)
    │   ├─ Aileron executes tools with user's OAuth token
    │   └─ Output: structured context summary
    │
    ├─ Round 2: Ghostwrite — LLM composes the reply
    │   ├─ Streaming: text deltas flow to Slack in real time
    │   └─ Output: the draft
    │
    ▼
Delivery
    ├─ Agent DM: streamed via chat.startStream/appendStream/stopStream
    ├─ Modal: views.update with editable draft + Send button
    └─ Slash command question: ephemeral response via response_url
    │
    ▼
User clicks Send → Aileron posts reply as user via xoxp- token

Context retrieval tools

The LLM can call these tools during draft generation:

Draft lifecycle API

Drafts are also available via REST:

Security

• Signature verification: HMAC-SHA256 with the signing secret. Invalid or stale (>5min) signatures rejected.
• No JWT auth on webhooks: The webhook endpoints are excluded from Aileron’s JWT middleware — Slack calls them directly. Signature verification provides authentication.
• Event deduplication: In-memory TTL map by event_id (5 minutes).
• Token storage: User OAuth tokens stored in the user vault (encrypted with per-user KEK). Bot tokens in the system vault (encrypted with system key).
• Read/write boundary (ADR-0019): The LLM reads via tools. Aileron owns all writes (sending messages). User approval required via Send button.