Slack MCP Server

Slack MCP without OAuth — 21 tools, session-based, local-first. Free OSS + hosted tier from $19/mo.

Remote serverstreamable-http

What is the Slack MCP server?

Most team communication work still happens through a UI a human drives. Slack MCP server moves it into the conversation instead. Slack MCP without OAuth — 21 tools, session-based, local-first. Free OSS + hosted tier from $19/mo.

The short version

Turn Slack from an interruption stream into searchable operating memory and approved action. The open-source local path ships 21 tools today through the browser session you already have—no Slack app, scope review, or admin queue. Hosted adds permanent OAuth, indexing, scheduled intelligence, and team continuity when the workflow must run without you.

The tools it exposes

The server publishes 4 tools. What each one is for:

  • slack_send_message — Send to a channel or DM
  • slack_add_reaction — Add an emoji reaction
  • slack_remove_reaction — Remove an emoji reaction
  • slack_conversations_mark — Mark a conversation read

Getting it running

Because this one is hosted, setup is mostly authentication — you point your client at the endpoint and approve access. Nothing runs on your machine, so there is no runtime to keep patched.

What it needs from you

Configuration is passed through the environment: SLACK_MCP_PROFILE, SLACK_TOKEN. Treat anything key-shaped as a real credential — scope it to the minimum the server needs, and rotate it if it ever lands in a shared config.

How it compares

Among the team communication options, the useful question is rarely "what can it do" but "what does it cost you to run" — permissions, credentials, and how much of your context its toolset consumes. Slack's toolset — slack_send_message, slack_add_reaction, slack_remove_reaction and 1 more — is a fair guide to whether it matches your workflow. It is maintained by jtalk222; worth a glance at recent repository activity before you build anything load-bearing on it.

This entry was verified against Slack's own documentation before publication; SyncDev keeps the directory reviewed rather than auto-generated.

Things to watch

  • Your data travels to the provider's service, so the usual questions apply about what you send and what they retain.
  • Missing credentials fail quietly in some clients — if no tools show up, check the environment block first.
  • Keep per-call confirmation enabled while you learn its behaviour; it is the cheapest safeguard you have.

Available tools

ToolWhat it does
slack_send_messageSend to a channel or DM
slack_add_reactionAdd an emoji reaction
slack_remove_reactionRemove an emoji reaction
slack_conversations_markMark a conversation read

How to install the Slack MCP server

{
  "mcpServers": {
    "slack-1": {
      "command": "npx",
      "args": ["-y", "@jtalk22/slack-mcp"],
      "env": {
        "SLACK_MCP_PROFILE": "your-value",
        "SLACK_TOKEN": "your-value"
      }
    }
  }
}

Add to claude_desktop_config.json, then restart Claude Desktop.

Configuration

VariableDescriptionRequired
SLACK_MCP_PROFILEConfiguration value read at startup.Optional
SLACK_TOKENCredential the server authenticates with.Yes

Example prompts to try

  • Use Slack to slack send message.
  • Use Slack to slack add reaction.
  • Use Slack to slack remove reaction.

Frequently asked questions

It connects Slack to MCP-compatible AI assistants such as Claude and Cursor, exposing 4 tools (slack_send_message, slack_add_reaction, slack_remove_reaction, and more) that the assistant can call on your behalf. Instead of copying data back and forth by hand, the assistant works with Slack directly.