korotovsky/slack-mcp-server

Model Context Protocol (MCP) server for Slack Workspaces. The most powerful MCP Slack server — supports Stdio, SSE and HTTP transports, proxy settings, DMs, Group DMs, Smart History fetch (by date or count), may work via OAuth or in complete stealth mode with no permissions and scopes in Workspace 😏.
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This feature-rich Slack MCP Server has:
- **Stealth and OAuth Modes**: Run the server without requiring additional permissions or bot installations (stealth mode), or use secure OAuth tokens for access without needing to refresh or extract tokens from the browser (OAuth mode).
- **Enterprise Workspaces Support**: Possibility to integrate with Enterprise Slack setups.
- **Channel and Thread Support with #Name @Lookup**: Fetch messages from channels and threads, including activity messages, and retrieve channels using their names (e.g., #general) as well as their IDs.
- **Smart History**: Fetch messages with pagination by date (d1, 7d, 1m) or message count.
- **Unread Messages**: Get all unread messages across channels efficiently with priority sorting (DMs > partner channels > internal), @mention filtering, and mark-as-read support.
- **Search Messages**: Search messages in channels, threads, and DMs using various filters like date, user, and content.
- **Safe Message Posting**: The conversations_add_message tool is disabled by default for safety. Enable it via an environment variable, with optional channel restrictions.
- **DM and Group DM support**: Retrieve direct messages and group direct messages.
- **Embedded user information**: Embed user information in messages, for better context.
- **Cache support**: Cache users and channels for faster access.
- **Stdio/SSE/HTTP Transports & Proxy Support**: Use the server with any MCP client that supports Stdio, SSE or HTTP transports, and configure it to route outgoing requests through a proxy if needed.
Analytics Demo
Add Message Demo
Tools
1. conversations_history:
Get messages from the channel (or DM) by channel_id, the last row/column in the response is used as 'cursor' parameter for pagination if not empty
- **Parameters:**
- channel_id (string, required): - channel_id (string): ID of the channel in format Cxxxxxxxxxx or its name starting with #... or @... aka #general or @username_dm.
- include_activity_messages (boolean, default: false): If true, the response will include activity messages such as channel_join or channel_leave. Default is boolean false.
- cursor (string, optional): Cursor for pagination. Use the value of the last row and column in the response as next_cursor field returned from the previous request.
- limit (string, default: "1d"): Limit of messages to fetch in format of maximum ranges of time (e.g. 1d - 1 day, 1w - 1 week, 30d - 30 days, 90d - 90 days which is a default limit for free tier history) or number of messages (e.g. 50). Must be empty when 'cursor' is provided.
2. conversations_replies:
Get a thread of messages posted to a conversation by channelID and thread_ts, the last row/column in the response is used as cursor parameter for pagination if not empty.
- **Parameters:**
- channel_id (string, required): ID of the channel in format Cxxxxxxxxxx or its name starting with #... or @... aka #general or @username_dm.
- thread_ts (string, required): Unique identifier of either a thread’s parent message or a message in the thread. ts must be the timestamp in format 1234567890.123456 of an existing message with 0 or more replies.
- include_activity_messages (boolean, default: false): If true, the response will include activity messages such as 'channel_join' or 'channel_leave'. Default is boolean false.
- cursor (string, optional): Cursor for pagination. Use the value of the last row and column in the response as next_cursor field returned from the previous request.
- limit (string, default: "1d"): Limit of messages to fetch in format of maximum ranges of time (e.g. 1d - 1 day, 1w - 1 week, 30d - 30 days, 90d - 90 days which is a default limit for free tier history) or number of messages (e.g. 50). Must be empty when 'cursor' is provided.
3. conversations_add_message
Add a message to a public channel, private channel, or direct message (DM, or IM) conversation by channel_id and thread_ts.