> ## 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.

# Add comment

> Add a comment to a Trello card.

`addComment` posts plain text to a card's activity.

```ts automations/comment-on-trello-card.automation.ts theme={null}
import { automation, onHttpRequest } from "automate.ax"
import { addComment } from "automate.ax/trello"

export default automation("Comment on Trello card", () => {
  onHttpRequest({ scope: "automation" })
  addComment({ card: "card-id", text: "Ready for review." })
})
```

`card` (ID, short link, or URL) and non-empty `text` are required. Optional `account` defaults to the project binding.

Returns `Signal<TrelloComment>` with action `id`, `text`, `commentedAt: Date`, and nullable `creator`. Keep the returned `id` for update or deletion.