Claude MCP Slack MCP Server

Standalone Slack MCP server for Claude Code Action

Local serverstdioTypeScript

What is the Claude MCP Slack MCP server?

Connect Claude MCP Slack to Claude, Cursor or any other MCP client and it stops being a tab you switch to. Standalone Slack MCP server for Claude Code Action. The claude mcp slack mcp server is what makes that connection.

What the server does

A standalone GitHub Action that provides Slack MCP (Model Context Protocol) server functionality for Claude Code Action, enabling secure Slack image downloads and integrations.

  • 🔐 Secure Slack Integration: Authenticated access to Slack files using Bot User OAuth tokens
  • 📁 Flexible File Management: Customizable download directories with security validation
  • 🐳 Docker Support: Run locally or in containers with proper security constraints
  • 🛡️ Security First: Input validation, path traversal prevention, and secure token handling
  • 🧪 Comprehensive Testing: Unit, integration, and security test suites
  • Easy Integration: Drop-in compatibility with claude-code-action

Installation

Setup follows the usual MCP pattern — install or clone the server, register it in your client's configuration file, restart the client. The configuration blocks on this page cover the common clients.

Available tools

The toolset is worth reading before you wire it up, because it tells you what the integration is really for:

  • name — Setup Slack MCP
  • Inputs — The Inputs tool exposed by this server
  • Outputs — The Outputs tool exposed by this server
  • slack_image_download — The slack_image_download tool exposed by this server
  • slack_health_check — Checks the health and configuration of the Slack MCP server
  • Testing — The Testing tool exposed by this server

Credentials and setup notes

Configuration is passed through the environment: API_KEY, SLACK_TOKEN, ANTHROPIC_API_KEY, CUSTOM_API_KEY. 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.

Worth knowing first

  • It runs with your machine's permissions. That is convenient and also the reason to think about what you point it at before you approve a tool call.
  • 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.

Where it fits

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. Claude MCP Slack's toolset — name, Inputs, Outputs and 3 more — is a fair guide to whether it matches your workflow. It is maintained by atlasfutures; worth a glance at recent repository activity before you build anything load-bearing on it.

We check each listing at SyncDev against the project's documentation before it goes live — if something here drifts out of date, it is a bug worth reporting.

Available tools

ToolWhat it does
nameSetup Slack MCP
InputsThe Inputs tool exposed by this server.
OutputsThe Outputs tool exposed by this server.
slack_image_downloadThe slack_image_download tool exposed by this server.
slack_health_checkChecks the health and configuration of the Slack MCP server.
TestingThe Testing tool exposed by this server.

How to install the Claude MCP Slack MCP server

### Advanced Configuration

```yaml
- name: Setup Slack MCP
  uses: atlasfutures/claude-mcp-slack@v1
  with:
    slack_token: ${{ secrets.SLACK_TOKEN }}
    download_directory: "./slack-assets"
  id: slack-mcp

- name: Claude Code Action with Multiple MCP Servers
  uses: anthropics/claude-code-action@main
  with:
    mcp_config: |
      {
        "mcpServers": {
          "slack": ${{ steps.slack-mcp.outputs.mcp_config }}.mcpServers.slack,
          "custom": {
            "command": "node",
            "args": ["custom-server.js"],
            "env": {
              "API_KEY": "${{ secrets.CUSTOM_API_KEY }}"
            }
          }
        }
      }
    anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}

Configuration as documented by the project. Restart the client after saving.

Configuration

VariableDescriptionRequired
API_KEYCredential the server authenticates with.Yes
SLACK_TOKENCredential the server authenticates with.Yes
ANTHROPIC_API_KEYCredential the server authenticates with.Yes
CUSTOM_API_KEYCredential the server authenticates with.Yes

Example prompts to try

  • Use Claude MCP Slack to name.
  • Use Claude MCP Slack to Inputs.
  • Use Claude MCP Slack to Outputs.

Frequently asked questions

It connects Claude MCP Slack to MCP-compatible AI assistants such as Claude and Cursor, exposing 6 tools (name, Inputs, Outputs, and more) that the assistant can call on your behalf. Instead of copying data back and forth by hand, the assistant works with Claude MCP Slack directly.