Mercury Banking

Log in to Mercury, go to Settings → API Tokens, and generate a new token. Copy it — you will need it in the next step. Use the minimum required scopes for your use case to limit exposure.

Add the mercury-invoicing-mcp server to your Claude Desktop config file at ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%/Claude/claude_desktop_config.json (Windows). Set MERCURY_API_KEY to your token.

{
  "mcpServers": {
    "mercury": {
      "command": "npx",
      "args": ["-y", "mercury-invoicing-mcp"],
      "env": {
        "MERCURY_API_KEY": "your-mercury-api-token"
      }
    }
  }
}

Set MERCURY_MCP_DRY_RUN=true to preview write operations (invoice creation, transfers, webhook changes) without actually executing them. This is strongly recommended for initial testing.

{
  "mcpServers": {
    "mercury": {
      "command": "npx",
      "args": ["-y", "mercury-invoicing-mcp"],
      "env": {
        "MERCURY_API_KEY": "your-mercury-api-token",
        "MERCURY_MCP_DRY_RUN": "true",
        "MERCURY_MCP_AUDIT_LOG": "/tmp/mercury-audit.json"
      }
    }
  }
}

Mercury provides a sandbox environment. If your API token starts with mercury_sandbox_, the server will automatically route requests to the dummy environment, letting you test all 36 tools without touching real funds.

Restart Claude Desktop to load the server. Ask Claude to list your Mercury accounts — if the connection is working, you will see your account names and balances returned.