> ## Documentation Index
> Fetch the complete documentation index at: https://docs.automate.ax/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Automate.ax automations are TypeScript programs.
> Use Bun for installation and command examples.
> Use Automate.ax for the product name and automate.ax for the package, CLI, and domain.
> Treat documented public APIs as current; do not invent transitional or deprecated names.

# On channel member left

> Run an automation when a member leaves a Slack conversation.

`slack.onChannelMemberLeft` emits `member_left_channel` events for conversations visible to the installed bot.

```ts automations/watch-slack-membership.automation.ts theme={null}
import { automation } from "automate.ax"
import { slack } from "automate.ax/slack"

export default automation("Watch Slack membership", () => {
  const membership = slack.onChannelMemberLeft()
  // Use membership.userId to revoke channel-specific access.
})
```

The result includes `userId`, `conversationId`, `conversationTypeCode` (`"C"` or `"G"`), the typed original `event`, and the complete `envelope`. Slack's membership event does not distinguish public from private conversations; use `slack.getSlackConversation` when that distinction matters.