1. Access Slack API platform;
2. Click "Get Started" button;
3. Click "Go to Your Apps" button then;
4. Click green "Create New App" button;
5. Create new application "From Scratch" for custom configuration;
6. Choose descriptive name (e.g., "AI Assistant" or personal identifier);
7. Select target Slack workspace from dropdown menu.

• In the side menu, choose "OAuth & Permissions";
• To make the "Install to Workspace" button active, scroll down to the "Scope" section;
• In the "User Token Scopes" subsection, click "Add an Oauth Scope";
• One-by-one, add the following scopes:
  • channels:history - read message history from public channels;
  • channels:read - access basic channel information;
  • chat:write - send messages to channels and users;
  • reactions:read - view emoji reactions on messages;
  • reactions:write - add emoji reactions to messages;
  • users:read - access basic user profile information.
• Scroll up and now click "Install to Workspace" button;
• In a new window, get acquainted with the requested permissions and allow them by clicking "Allow";
• Now, you have received an OAuth Token that starts with xoxp-. Don't close the window for future use.

• Open the target Slack workspace in a browser;
• Or open the Slack Desktop window;
• Click the workspace name to access settings;
• Copy the workspace URL and paste it to the browser address bar or write it manually;
• Locate Team ID in the URL structure (appears after "T" prefix);
• Don't close this browser tab as well.

• In Claude, type this prompt:

Clone this MCP server to the Documents/projects folder and run the commands

git clone https://github.com/lars-hagen/slack-user-mcp.git
cd slack-user-mcp
npm install
npm run build

• Run the prompt.

• In Claude, paste the prompt:

Add this block to the Claude config file
{
  "mcpServers": {
    "slack": {
      "command": "npm",
      "args": [
        "run",
        "--prefix",
        "/path/to/slack-user-mcp",
        "start"
      ],
      "env": {
        "SLACK_TOKEN": "xoxp-your-user-token",
        "SLACK_TEAM_ID": "T01234567"
      }
    }
  }
}

• Add two required parameters inside the block:
  • Slack token (starts with xoxp-) → copy it from the Slack API page;
  • Slack team ID (starts with T) → copy it from the workspace URL.

Both values are sensitive. Do not share them. Claude Desktop runs locally, so it is safe to paste them here.

• Run the prompt.

• Fully exit Claude Desktop (macOS: Cmd + Q, Windows: Alt + F4);
• Re-open Claude.

Some warnings may appear — ignore them. These do not affect functionality.

• Open the Termianl (Mac) or Command Line (Windows);
• Navigate to the directory where you store AI agents repos by cd command, for example:

cd Documents/projects

• Download the Slack MCP server repository from GitHub to your local machine:

git clone https://github.com/lars-hagen/slack-user-mcp.git

• Enter the newly created repository directory:

cd slack-user-mcp

• Install all required dependencies and packages for the Slack MCP server:

npm install

• Compile the project and create the build files needed for execution:

npm run build

• If you experience some problems in command execution in Terminal, use Command/Ctrl + C for process termination.

• Access Claude config via Command/Ctrl + ,;
• Open Developer tab and select "Edit Config";
• Add Slack MCP configuration block after existing entries;

    "slack": {
      "command": "npm",
      "args": [
        "run",
        "--prefix",
        "/path/to/slack-user-mcp",
        "start"
      ],
      "env": {
        "SLACK_TOKEN": "xoxp-...",
        "SLACK_TEAM_ID": "T..."
      }
    }

• Insert required credentials:
  • Repository path (from pwd command in the Terminal/Command line);
  • User OAuth Token xoxp-...(from Slack API);
  • Team ID T...(from workspace URL).
• Save the file.