Slack MCP Server

A Slack MCP server

Remote serverstreamable-http

What is the Slack MCP server?

A Slack MCP server. Exposed over MCP by the slack mcp server, that capability becomes something an assistant can invoke while it works, not something you go and do afterwards.

What it actually does

A MCP(Model Context Protocol) server for accessing Slack API. This server allows AI assistants to interact with the Slack API through a standardized interface.

  • slack_list_channels - List public channels in the workspace with pagination
  • slack_post_message - Post a new message to a Slack channel
  • slack_reply_to_thread - Reply to a specific message thread in Slack
  • slack_add_reaction - Add a reaction emoji to a message
  • slack_get_channel_history - Get recent messages from a channel
  • slack_get_thread_replies - Get all replies in a message thread

Its toolset

Everything the assistant can do here goes through one of these:

  • Installation — NOTE: Its now hosted in GitHub Registry so you need your PAT
  • Configuration — You can also create a .env file to set these environment variables:
  • Usage — The Usage tool exposed by this server
  • Contributing — 1. Fork the repository 2. Create your feature branch 3. Run tests and linting: npm run lint 4. Commit your changes 5. Push to the branch 6. Create a

Adding it to your client

Being a remote server, there is no local install. You register the endpoint with your client, authorise it once, and the tools appear.

Configuration

You will need 3 environment variables: SLACK_BOT_TOKEN, SLACK_USER_TOKEN, SLACK_SAFE_SEARCH. The server will not start without them, which is usually why the tools fail to appear on a first run. Keep credentials in your client's env block or a secrets manager rather than in a file you might commit.

When to reach for it

Plenty of team communication servers cover similar ground. The differences that matter in practice are scope of access and how much setup stands between you and a working tool call. Slack's toolset — Installation, Configuration, Usage and 1 more — is a fair guide to whether it matches your workflow. It is maintained by ubie-oss; worth a glance at recent repository activity before you build anything load-bearing on it.

SyncDev reviews every entry in this directory against the project's own documentation before publishing, and revisits them as servers change.

Caveats

  • 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.
  • MCP clients confirm each tool call by default. Leave that on until you have watched what the slack mcp server does with a few real requests.

Available tools

ToolWhat it does
InstallationNOTE: Its now hosted in GitHub Registry so you need your PAT.
ConfigurationYou can also create a .env file to set these environment variables:
UsageThe Usage tool exposed by this server.
Contributing1. Fork the repository 2. Create your feature branch 3. Run tests and linting: npm run lint 4. Commit your changes 5. Push to the branch 6. Create a Pull Request

How to install the Slack MCP server

{
  "mcpServers": {
    "slack-mcp-server-ubie-oss": {
      "command": "npx",
      "args": ["-y", "@ubie-oss/slack-mcp-server"],
      "env": {
        "SLACK_BOT_TOKEN": "your-value",
        "SLACK_USER_TOKEN": "your-value",
        "SLACK_SAFE_SEARCH": "your-value"
      }
    }
  }
}

Add to claude_desktop_config.json, then restart Claude Desktop.

Configuration

VariableDescriptionRequired
SLACK_BOT_TOKENCredential the server authenticates with.Yes
SLACK_USER_TOKENCredential the server authenticates with.Yes
SLACK_SAFE_SEARCHConfiguration value read at startup.Optional

Example prompts to try

  • Use Slack to Installation.
  • Use Slack to Configuration.
  • Use Slack to Usage.

Frequently asked questions

`SLACK_BOT_TOKEN` (bot user OAuth token) is required for most operations. `SLACK_USER_TOKEN` (user OAuth token) is needed for features like message search.