It acts as your own signed-in identity and cannot read a channel you cannot read, which is exactly why setup is one command instead of a request to IT. The cost is the session model itself: credentials rotate, and Enterprise Grid runs session-anomaly detection that can flag and kill a session — outbound calls are paced to stay under burst thresholds, and Grid users are pointed at OAuth instead.
A local server that reuses the Slack session already in Chrome rather than asking an admin to install a Slack app. It reads DMs, channels, threads and search results with user names resolved, and can reply, react and mark conversations read as you.
- Conversations with unread messages, ranked by unread count, so a morning catch-up starts where it should
- Channel and DM history with user names resolved, and blocks, attachments, files, reactions and metadata when text alone is not the message
- A whole conversation exported with all of its threads, optionally written to a file
- Workspace message search, plus user lookup and user search by name, display name or email
- Replies sent, reactions added or removed, conversations marked read — every write carries an MCP destructive annotation so the client can ask first
- Credential state on demand: token age, storage backend, cache stats, and a refresh straight from the browser session on macOS
- Workflow profiles saved locally, binding a kind — support_inbox, incident_room, exec_brief, product_launch_watch or custom — to channels, priority people and a cadence
- On the hosted tier: a structured catch-up per profile, thread triage with priority and suggested owner, and hybrid semantic search over indexed history
Node 22 or 24 is recommended and Node 20 still works. On macOS, npx -y @jtalk22/slack-mcp --setup lifts the session out of Chrome — the token from its LevelDB, the cookie from its SQLite store, decrypted locally against the Keychain — and transmits nothing. On other platforms you supply SLACK_TOKEN and SLACK_COOKIE from that session yourself. Those credentials rotate, commonly after a week or two; slack_refresh_tokens or a second --setup recovers them. SLACK_MCP_PROFILE keeps work and personal workspaces separate, and SLACK_MCP_TOOLS=essentials advertises six tools rather than the full set when schema size per turn matters. slack_catch_me_up, slack_triage and slack_smart_search run on the hosted OAuth tier at mcp.revasserlabs.com, whose free plan covers 25 AI tool calls a month.
One command plus a key — npx -y @jtalk22/slack-mcp --setup, then supply credentials