How to use the Slack Actions agent skill

What is an agent skill, and what does the Slack skill do?

An agent skill is a folder containing a SKILL.md file that tells an AI agent when to use a tool and how to call it. This skill is named slack and is designed for Brigade. It tells the agent to use the slack tool to act in Slack channels or DMs.

The skill covers reactions, pins, messages, member info and the custom emoji list. The tool uses the bot token configured for Brigade, so actions appear as coming from that bot.

• React to messages with an emoji, and list the reactions on a message.
• Pin or unpin a message, and list pinned items in a channel.
• Send, edit or delete messages, and read recent messages from a channel.
• Look up member info for a user ID, and list custom emoji.

Install the Slack skill

Download the ZIP for this skill from this page. Then install it in one of two ways.

Option 1: unzip it into your personal skills folder ~/.claude/skills/, or into a project's .claude/skills/ folder if you want it limited to one project.

Option 2: in the Claude apps, open Settings, go to Capabilities, and upload the skill under Skills.

Check the requirements before you start

The skill depends on a working Brigade Slack setup. It will not work on its own. Confirm that the following are in place before you ask the agent to act in Slack.

• Brigade is set up with the channels.slack configuration.
• A Slack bot token is configured for Brigade.
• You have the Slack channel ID and message ID for any message you want to act on.

Give the agent the right inputs

Most actions need a channelId and a messageId. A message ID is a Slack message timestamp, for example 1712023032.1234. For reactions you also need an emoji, either as Unicode or as a :name: code. For sending, you need a to target in the form channel:<id> or user:<id>, plus the content.

Message context lines in Brigade include slack message id and channel fields. You can reuse these values directly instead of looking them up.

Ask for actions in natural language

You do not need to write JSON yourself. Describe the outcome you want, and include the channel and message details the agent needs. The skill's description means the agent will reach for it when a request involves Slack reactions or pins.

Examples of requests that fit the skill are shown below. Name the channel or message clearly so the agent does not guess.

• React with ✅ to message 1712023032.1234 in channel C123 to mark it done.
• Pin message 1712023032.1234 in C123, since it is this week's decision.
• Read the last 20 messages in C123 and summarise the open questions.
• Send 'Weekly status is posted below' to channel:C123.
• Show the reactions on message 1712023032.1234 in C123.

Reference: the actions the skill supports

The skill defines these actions. Each is a JSON object with an action field. The five action groups (reactions, messages, pins, memberInfo and emojiList) are all enabled by default in the file.

React uses action react with channelId, messageId and emoji. Reactions lists them with action reactions. Pin and unpin use pinMessage and unpinMessage, and listPins takes a channelId. Messages use sendMessage, editMessage, deleteMessage and readMessages, where readMessages accepts a limit. Member info takes a userId, and emojiList needs no other fields.

Safety notes: network use, scripts and irreversible actions

This skill uses the network, because it calls Slack through the Brigade tool. It does not run scripts. Its file gives no confirmation step, so the agent will carry out an edit or delete as soon as it is asked.

Deletions and edits are irreversible from the skill's side. Before you enable it in a shared workspace, decide who can make requests and consider whether an agent posting or removing messages could confuse people. If that risk is unacceptable, do not install the skill there.

• Review each request before the agent sends, edits or deletes a message.
• Use a bot token with only the permissions your workflow needs.
• Keep the skill out of workspaces where unexpected bot posts would be disruptive.

Tips for good results

The skill works best for simple, specific tasks. Give exact IDs and say what you want done. The file suggests two starter uses: reacting with ✅ to mark completed tasks, and pinning key decisions or weekly status updates.

• Use the message timestamp exactly as Slack shows it, such as 1712023032.1234.
• Ask for a single action at a time when you are testing.
• Start by reading messages or listing pins before you edit or delete anything.