> ## 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 checklist item completed

> Run an automation after a Trello checklist item is completed.

`trello.onChecklistItemCompleted` matches an `updateCheckItemStateOnCard` action whose item state is `"complete"`.

```ts automations/watch-trello-checklist-completions.automation.ts theme={null}
import { automation } from "automate.ax"
import { trello } from "automate.ax/trello"

export default automation("Watch Trello checklist completions", () => {
  trello.onChecklistItemCompleted({ board: "board-id" })
})
```

Provide `board` as an ID, short link, or URL. Optional static `account` defaults to the project binding.

Returns a resource event with `actionType: "updateCheckItemStateOnCard"`, required `checkItem.state: "complete"` and `board`, plus `actionId`, `occurredAt`, optional `checklist`, `card`, `memberCreator`, and the complete provider `event`. The action also matches `trello.onChecklistItemUpdated`.