Show the server version, which Slack bot and workspace this server is connected to, the connection mode, the OAuth scopes the bot has, and which tools are missing scopes. Call this first when a Slack action fails with a permission error.

Find workspace members by email, real name, display name, @handle or job title. Returns user IDs to use with send_message and other tools. Exact matches come first.

Get profile details for one Slack user, identified by user ID (U…), email, or @handle.

List channels the bot can see, optionally filtered by name. Private channels and DMs appear only if the bot is a member. is_member: false means the bot must be invited before it can post there (unless it has chat:write.public).

Post a message as the bot to a channel, a thread, or a user's DM. target accepts a channel ID (C…), #channel-name, user ID (U…), @handle, email, or a person's name; users get a direct message. Use context to add small reference details under a divider at the bottom (Jira ticket, comment link, source, IDs). Use blocks only when you need a custom Block Kit layout (header, fields, images, etc.). Returns the message ts, which you can pass to wait_for_reply or use as thread_ts to reply in a thread.

Replace the content of a message the bot posted, identified by channel and ts (as returned by send_message). Slack only lets a bot edit its own messages. The new text, context and blocks fully replace the old content, so resend any context you want to keep.

Delete a message the bot posted, identified by channel and ts (as returned by send_message). Slack only lets a bot delete its own messages. Deleting the parent of a thread leaves its replies in place. This cannot be undone, so confirm with the user unless they asked for it.

Read recent messages from a channel or DM, newest first. channel accepts a channel ID, #channel-name, or a user (ID, @handle, email) for the bot's DM with them. Use cursor from the previous response to page further back. Thread replies are not included; use conversations_replies for those.

Read the replies in a thread, oldest first, including the parent message. thread_ts is the ts of the parent message (or of any message in the thread).

Add an emoji reaction to a message as the bot.

Remove an emoji reaction the bot previously added to a message.

Return direct messages and @mentions the bot received while this MCP server was running. Only covers events delivered to this process: messages sent before it started, or delivered to another running instance of the same Slack app, are not here. To reliably fetch replies in a known channel or thread, use wait_for_reply or conversations_history.

Block for a short time until someone other than the bot replies in a channel, DM or thread, then return the new messages. Use it only when an answer is likely within a minute or two; every call costs a model turn. Pass since_ts = the ts of your question (from send_message). Replies both as new messages and inside the question's thread are found. On replied: false, follow the returned next_step: after a couple of timeouts, stop waiting, tell the user, and collect the answer later with check_replies. Keep timeout_seconds below your MCP client's tool-call timeout (often 60 seconds; Claude Code users can raise it with MCP_TOOL_TIMEOUT).

Check once, without waiting, whether people answered the bot. With no arguments, checks every pending question (saved by send_message with expect_reply, or by wait_for_reply on timeout), including ones from earlier sessions; answered questions are removed from the pending list. With channel and since_ts, checks one conversation instead. Cheap to call, so use it for long waits: end your turn, then call it later from a scheduled or looped run.