Auto-Acknowledge New Trello Intake Cards with Instructions and Slack Alerts

An intake list only works if requesters trust that someone is watching it. This blueprint makes the acknowledgement automatic: io.kestra.plugin.trello.cards.Trigger polls the intake list, and for every new card the flow posts the intake instructions as a comment through io.kestra.plugin.trello.cards.Comment and summarizes the batch in Slack. Requesters hear back within the polling interval, and the team sees intake volume in chat without opening the board.

How it works

1. The watch_intake trigger (io.kestra.plugin.trello.cards.Trigger) polls the configured list every five minutes and fires one execution per batch of detected cards. It ships disabled: true; point lists at your intake list id before enabling.
2. The trigger exposes the batch as {{ trigger.cards }}, where each card carries cardId, cardName, cardUrl, listId, and an action label, plus {{ trigger.count }} for the batch size.
3. loop_cards (io.kestra.plugin.core.flow.Loop) iterates over the batch. Inside the loop, {{ fromJson(item.value).cardId }} addresses the current card.
4. comment_instructions (io.kestra.plugin.trello.cards.Comment) posts the intake checklist on the card, quoting the card name so the comment reads as a personal acknowledgement.
5. notify posts the batch count to Slack, and the errors block raises a distinct alert when acknowledgement fails, since an unanswered intake list erodes trust fastest.

What you get

• Every new request acknowledged within the polling interval, with concrete next steps.
• Batch-safe processing: five cards arriving together produce five comments, not one.
• Intake volume visible in Slack without anyone watching the board.
• A failure alert for the silent-intake failure mode.

Who it's for

• Teams running request intake through a Trello list: IT, design, data, or internal tooling.
• Ops leads who want a service-desk feel without adopting a service desk.
• Anyone whose intake column has become a place where requests go quiet.

Why orchestrate this with Kestra

Trello has no built-in way to run logic when a card appears. Kestra supplies the polling trigger with batch semantics, the loop over detected cards, secret management for the API credentials, and an execution history that shows exactly which cards were acknowledged and when.

Prerequisites

• A Trello board with an intake list, and that list's id for the trigger's lists property.
• A Trello API key and token from https://trello.com/power-ups/admin.
• A Slack incoming webhook for batch summaries and failure alerts.

Secrets

• TRELLO_API_KEY: Trello API key.
• TRELLO_API_TOKEN: Trello API token.
• SLACK_WEBHOOK_URL: Slack incoming webhook URL.

Quick start

1. Add the three secrets to your Kestra namespace.
2. Replace replace-with-your-intake-list-id with your intake list id.
3. Set disabled: false on the watch_intake trigger, drop a card into the list, and check the comment plus the Slack summary.

How to extend

• Tailor the instruction text per list by watching several lists and branching on {{ fromJson(item.value).listId }} with io.kestra.plugin.core.flow.If.
• Set a response-time expectation by adding a due date to each card with io.kestra.plugin.trello.cards.Update.
• Shorten interval for a snappier acknowledgement, or lengthen it for low-traffic boards.
• Include {{ fromJson(item.value).cardUrl }} in the Slack payload to deep-link each card.

Links

• Trello plugin documentation
• Trello REST API documentation