Slack MCP Server implements a Go-based MCP server for Slack with multiple transports, stealth/OAuth modes, and rich history/search features. It includes DM/Group DM support, channel/thread access, and various admin/tools controls via a documented API.
Collecting history — the radar snapshots this repo daily. The trend line appears after 3 days of data (1 so far).
What it is
Slack MCP Server is a Model Context Protocol (MCP) server for Slack Workspaces written in Go. It supports Stdio, SSE and HTTP transports, proxy settings, DMs, Group DMs, Smart History fetch (by date or count), and can operate with or without permissions (stealth mode) using OAuth or in stealth mode.
How it works
The repository exposes a set of MCP tools/endpoints to interact with Slack data, including conversations_history, conversations_replies, conversations_add_message, conversations_search_messages, channels_list, reactions_add, reactions_remove, users_search, usergroups_list, usergroups_create, usergroups_update, usergroups_users_update, usergroups_me, and conversations_unreads. These tools provide access to channel/DM history, message posting, searching, channel listing, reactions, user/group management, and unread message retrieval, with configurable filters and pagination.
Getting started
- The README provides command-like usage for each tool, including parameters and defaults as described under each tool section. For example, conversations_history accepts channel_id, include_activity_messages, cursor, and limit (default: 1d).
- The README includes environment-variable related notes for enabling certain features (e.g., SLACK_MCP_ADD_MESSAGE_TOOL, SLACK_MCP_REACTION_TOOL) and mentions OAuth vs. stealth operation modes.
Recent releases
- v1.3.0 (2026-05-14): fix non-blocking stdio startup and --no-cache flag; fix incorrect env var references for reactions.
- v1.2.3 (2026-03-03): fix channels_list empty results on Enterprise Grid with xoxc/xoxd tokens; allow to filter out u.
- v1.2.2 (2026-02-25): (no changes described in provided notes).
- v1.1.28 (2025-12-09): add Slack manifest to XOXP configuration; fix: preserve user IDs in channel cache for DM name display.
- v1.1.26 (2025-10-11): fix pagination; fix filter by private channel id/name.
Traction
- stars: 1765
- forks: 348
- open_issues: 58
Behind the repo
- license: MIT
- language: Go
- created: 2025-04-12
- last_push: 2026-07-16
Caveats
- The README notes that posting messages via conversations_add_message is disabled by default and can be enabled by setting the SLACK_MCP_ADD_MESSAGE_TOOL environment variable.
- Reactions and certain tools mention environment-variable based enablement (SLACK_MCP_REACTION_TOOL).
- OAuth scopes and token compatibility are described for various tools (e.g., usergroups:read/write, bot tokens constraints in search).