Slack MCP Server

Search and read public-channel Slack discussions about Jira tickets and PRs, and send/reply to messages only after an explicit two-step confirmation.

What it can and can't do

• Reads public channels only. DMs, private channels, and group DMs are refused by a server-side guard — even though the user token could see them.
• Search uses Slack's search.messages, which requires a user token.
• Sending is two-step: draft_message returns a preview + one-time token; nothing posts until you call send_message with that token.

Slack app setup

1. Create an app at https://api.slack.com/apps.
2. Under OAuth & Permissions → User Token Scopes, add: search:read, channels:history, channels:read, users:read, chat:write.
3. Install the app to your workspace and copy the User OAuth Token (xoxp-...).

Configuration

export SLACK_USER_TOKEN="xoxp-..."          # required
export SLACK_DRAFT_TTL_SECONDS=300           # optional, default 300

Run

uv sync
uv run slack-mcp

MCP client config

{
  "mcpServers": {
    "slack": {
      "command": "uv",
      "args": ["run", "slack-mcp"],
      "cwd": "/absolute/path/to/slack-mcp",
      "env": { "SLACK_USER_TOKEN": "xoxp-..." }
    }
  }
}

Tools

• search_messages(query, count=20) — find messages in public channels.
• read_thread(channel, thread_ts) — full thread with resolved names.
• read_channel_history(channel, limit=30, around_ts=None) — recent/context.
• list_channels(name_filter=None) — public channels.
• resolve_users(user_ids) — ids → display names.
• draft_message(channel, text, thread_ts=None) — preview + token; does NOT send.
• send_message(confirmation_token) — sends the drafted message (only write path).