slack

name	slack
description	Compose, search, and post to Slack channels, DMs, and canvases.
plugin	slack

Slack

The Slack MCP plugin exposes the same 13 tools shipped by the official Slack Claude Code plugin. The full schemas land in your tool list at session start; this skill summarises how to sequence them well.

Workflows

Posting a message to a known channel name

If you only know the channel by name (e.g. #releases, not its C… ID):

1. slack_search_channels(query: "releases") → returns the channel's id (looks like C09RELEASE01).
2. slack_send_message(channel_id: "C09…", message: "...") → posts and returns message_link. Quote the link in your final answer.

Posting a DM

channel_id may be a user_id for DMs. Resolve the user via slack_search_users(query: "name or email"), then pass their id as channel_id to slack_send_message.

Drafts instead of sends

If the user hasn't approved exact wording, prefer slack_send_message_draft(channel_id, message) over slack_send_message. A draft can be reviewed in Slack's UI before it's sent.

Searching

• slack_search_public — public channels only; safe to call without user confirmation.
• slack_search_public_and_private — includes DMs and private channels; ask first if uncertain.
• Use search modifiers in the query string: in:#channel, from:@user, before:YYYY-MM-DD, after:YYYY-MM-DD, is:thread, quotes for exact phrases.

Reading a thread

You need both the parent channel_id AND the parent message_ts. If you only have a search hit, pull the ts from the result and pass it as message_ts to slack_read_thread.

Gotchas

• Markdown, not Slack mrkdwn. slack_send_message accepts standard markdown (**bold**, _italic_, `code`). Don't use Slack's older *bold*/_italic_ mrkdwn syntax.
• No Connect channels. Posting to externally-shared (Slack Connect) channels is not supported by these tools.
• Canvas Markdown is its own dialect. When using slack_create_canvas / slack_update_canvas, the content uses Canvas-flavored Markdown (user refs as ![](@U…), channel refs as ![](#C…), ATX headings only). The full spec is embedded in the tool's description — read it before writing canvas content.
• Current user is U09J02RP7MK. Use this when the task says "me" or asks to DM the runner themselves.