One command does the whole thing, no file editing needed. Run this from anywhere, with your real values from Step 6 in place of the two placeholders:

claude mcp add looker-toolbox --scope user \
  --env LOOKER_BASE_URL=https://intelligence.foreman.mn \
  --env LOOKER_CLIENT_ID=your-client-id \
  --env LOOKER_CLIENT_SECRET=your-client-secret \
  --env LOOKER_VERIFY_SSL=true \
  -- /opt/homebrew/bin/toolbox --stdio --prebuilt looker

If you ever need to check or fix it later, the entry lives in ~/.claude.json under "mcpServers" and should look like:

"looker-toolbox": {
  "type": "stdio",
  "command": "/opt/homebrew/bin/toolbox",
  "args": ["--stdio", "--prebuilt", "looker"],
  "env": {
    "LOOKER_BASE_URL": "https://intelligence.foreman.mn",
    "LOOKER_CLIENT_ID": "your-client-id",
    "LOOKER_CLIENT_SECRET": "your-client-secret",
    "LOOKER_VERIFY_SSL": "true"
  }
}

One command does the whole thing, no file editing needed. Run this from PowerShell, with your real values from Step 6 in place of the two placeholders:

claude mcp add looker-toolbox --scope user `
  --env LOOKER_BASE_URL=https://intelligence.foreman.mn `
  --env LOOKER_CLIENT_ID=your-client-id `
  --env LOOKER_CLIENT_SECRET=your-client-secret `
  --env LOOKER_VERIFY_SSL=true `
  -- "$env:LOCALAPPDATA\mcp-toolbox\toolbox.exe" --stdio --prebuilt looker

If you ever need to check or fix it later, the entry lives in %USERPROFILE%\.claude.json under "mcpServers" and should look like this, with your-username being your Windows account name (note the doubled backslashes JSON needs in the path):

"looker-toolbox": {
  "type": "stdio",
  "command": "C:\\Users\\your-username\\AppData\\Local\\mcp-toolbox\\toolbox.exe",
  "args": ["--stdio", "--prebuilt", "looker"],
  "env": {
    "LOOKER_BASE_URL": "https://intelligence.foreman.mn",
    "LOOKER_CLIENT_ID": "your-client-id",
    "LOOKER_CLIENT_SECRET": "your-client-secret",
    "LOOKER_VERIFY_SSL": "true"
  }
}

{
  "mcpServers": {
    "looker-toolbox": {
      "command": "/opt/homebrew/bin/toolbox",
      "args": ["--stdio", "--prebuilt", "looker"],
      "env": {
        "LOOKER_BASE_URL": "https://intelligence.foreman.mn",
        "LOOKER_CLIENT_ID": "your-client-id",
        "LOOKER_CLIENT_SECRET": "your-client-secret",
        "LOOKER_VERIFY_SSL": "true"
      }
    }
  }
}

Three things to replace in this block, not two: your-username in the "command" path has to be your Windows account name (run whoami in PowerShell and use the part after the backslash), plus the Client ID and Secret. Keep the doubled backslashes.

{
  "mcpServers": {
    "looker-toolbox": {
      "command": "C:\\Users\\your-username\\AppData\\Local\\mcp-toolbox\\toolbox.exe",
      "args": ["--stdio", "--prebuilt", "looker"],
      "env": {
        "LOOKER_BASE_URL": "https://intelligence.foreman.mn",
        "LOOKER_CLIENT_ID": "your-client-id",
        "LOOKER_CLIENT_SECRET": "your-client-secret",
        "LOOKER_VERIFY_SSL": "true"
      }
    }
  }
}