Slack MCP Server

What jtalk22/slack-mcp-server does

jtalk22/slack-mcp-server MCP server gives an MCP client access to Slack conversations and workspace users through a focused local tool surface. It can list channels and DMs, retrieve channel or direct-message history, include thread replies, search messages, resolve user names, inspect unread conversations, and export a complete conversation to a file. The write operations cover sending messages, adding or removing reactions, and marking a conversation as read.

Workflow tools add a local profile layer. Profiles are stored in ~/.slack-mcp-workflows.json and can associate a workflow type with channels, priority people, retention behavior, and summary cadence. Supported workflow kinds include support inboxes, incident rooms, executive briefs, product launch watches, and custom profiles.

How it works

The local path runs over stdio and uses the Slack identity already present in Chrome. Setup reads the newest Slack xoxc- token from Chrome’s LevelDB, snapshots the cookie database and its WAL files, retrieves Chrome Safe Storage from the macOS Keychain, and decrypts the cookies locally. The material says this process does not transmit the extracted credentials; the server communicates with Slack.

Credential storage can use automatic selection, Keychain-only storage, or files. The server supports token health checks, refresh coordination, atomic writes, profile isolation, and fallback to the last known good in-memory credentials when persistence is temporarily unavailable. slack_refresh_tokens extracts refreshed credentials from Chrome and requires a Slack tab to be open there. Request pacing can be controlled with SLACK_MCP_MIN_REQUEST_INTERVAL_MS and SLACK_MCP_MAX_CONCURRENCY.

Setup and configuration

Install and run setup with:

npx -y @jtalk22/slack-mcp --setup

The project is intended for Claude Desktop, Cursor, Windsurf, Claude Code, and other stdio MCP clients. The supplied material specifically identifies the local transport as stdio, so the client must be configured to launch the package locally. No Slack app or admin request is required for this local session-based path, but it acts with the permissions of the signed-in Slack identity.

Tools and capabilities

The jtalk22/slack-mcp-server MCP server includes tools for:

• Checking token health, authentication state, refresh status, and cache statistics.
• Listing conversations, reading histories, retrieving threads, exporting full histories, and finding unread channels or DMs.
• Searching messages and searching workspace users by partial name, display name, or email.
• Inspecting user details and marking conversations read.
• Sending messages and managing reactions.
• Saving and listing workflow profiles.

Three hosted-only tools extend the local features: slack_smart_search provides hybrid semantic and lexical search over indexed history; slack_catch_me_up produces structured workflow-specific catch-up output; and slack_triage classifies and routes threads. These hosted tools require Vectorize and Workers AI. Their free tier includes 25 AI tool calls per month, shared across hosted AI tools; Pro is listed at $19 per month for unlimited use.

Limitations and notes

Browser-session authentication is not the same as a sanctioned OAuth integration. Enterprise Grid may detect this access pattern and terminate the session; the material recommends hosted OAuth or Slack’s official MCP for Grid deployments. The local server cannot access channels unavailable to the signed-in user or act as another user. Workspace retention, DLP, compliance export, and audit controls still apply.

The hosted workflow features are separate from the local JSON profile primitives and are not available solely from the local tool process. Review the repository code and workspace policies before using a browser-session credential method.

Getting started with this jtalk22/slack-mcp-server MCP server

Always refer to the official documentation for the most accurate and up-to-date information.