MCP Integration

MCP is an open standard that lets AI assistants call external tools. The @engitoolbox/mcp package runs locally on your machine and exposes every EngiToolbox calculator as a tool the AI can invoke — stress analysis, beam calculations, speeds & feeds, and 33 more.

Each tool call is forwarded to the EngiToolbox REST API using your API key. Calculations run on our servers with the same accuracy as the website.

• A Pro, Team, or Enterprise subscription
• An API key from your dashboard
• Node.js 18 or later (for running the MCP server via npx)
• An MCP-compatible client (Cursor, Claude Desktop, etc.)

Free accounts cannot create API keys. MCP usage counts against your plan's monthly API quota — same as direct REST API calls.

1. Sign in and open your dashboard
2. Under API Keys, enter a name and click Create key
3. Copy the key immediately — it starts with et_ and is shown only once

Open Cursor Settings → MCP (or edit your MCP config file) and add the EngiToolbox server. Replace et_your_api_key_here with your key:

{
  "mcpServers": {
    "engitoolbox": {
      "command": "npx",
      "args": ["-y", "@engitoolbox/mcp"],
      "env": {
        "ENGITOOLBOX_API_KEY": "et_your_api_key_here"
      }
    }
  }
}

Restart Cursor or reload MCP servers. You should see 34 EngiToolbox tools available (named engitoolbox_*).

Edit your Claude Desktop config file (claude_desktop_config.json) and add the same server block under mcpServers:

{
  "mcpServers": {
    "engitoolbox": {
      "command": "npx",
      "args": ["-y", "@engitoolbox/mcp"],
      "env": {
        "ENGITOOLBOX_API_KEY": "et_your_api_key_here"
      }
    }
  }
}

Config file locations: macOS ~/Library/Application Support/Claude/, Windows %APPDATA%\Claude\.

Each calculator maps to one MCP tool. For example, engitoolbox_stress calculates axial stress, and engitoolbox_beam_analysis runs a full beam analysis.

See the interactive API reference for input schemas, examples, and response shapes — MCP tools use the same parameters.

MCP tool calls use the same quotas as the REST API:

Set ENGITOOLBOX_API_URL only when testing against a staging or local deployment.