@endiagram/mcp

MCP server for EN Diagram — deterministic structural analysis powered by graph theory. Every result is backed by a named mathematical theorem. No AI inside the computation.

Installation

Run directly:

npx @endiagram/mcp

Or install globally:

npm install -g @endiagram/mcp

Connect

Claude Code

claude mcp add endiagram npx @endiagram/mcp

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "endiagram": {
      "command": "npx",
      "args": ["@endiagram/mcp"]
    }
  }
}

Cursor

Add to .cursor/mcp.json in your project root:

{
  "mcpServers": {
    "endiagram": {
      "command": "npx",
      "args": ["@endiagram/mcp"]
    }
  }
}

HTTP (zero install)

Any MCP client that supports HTTP transport:

https://api.endiagram.com/mcp

Smithery

smithery mcp add dushyant30suthar/endiagram

Environment Variables

| Variable | Default | Description | |----------|---------|-------------| | EN_API_URL | https://api.endiagram.com | API endpoint for the EN Diagram service |

Tools

| Tool | Description | |------|-------------| | structure | Topology, bridges, bottlenecks, parallelism, critical path, dominator tree, subsystems | | invariant | Conservation laws, deadlock detection, boundedness, structural complexity | | live | Liveness analysis — can resources drain permanently? Can queues overflow? | | reachable | Path tracing between any two points — distance, intermediaries, defense coverage | | equivalent | Compare two systems or simulate a change — what breaks, what shifts | | compose | Extract or merge subsystems — interface boundaries, shared resources | | render | SVG diagram of the system |

EN Syntax

One statement per line:

actor do: action needs: input1, input2 yields: output1, output2

Shared names between yields and needs create connections automatically:

customer do: place order needs: menu yields: order
kitchen do: prepare food needs: order yields: meal
waiter do: deliver needs: meal yields: served customer

Learn more at endiagram.com.

Telemetry

@endiagram/mcp generates a random install ID on first run, stored at ~/.endiagram/install-id (mode 0600). It is sent with every request as the X-Endiagram-Install-Id HTTP header so we can correlate requests from the same install for debugging issues that the per-IP signal alone cannot track (mobile networks, VPNs, CGNAT all collapse or churn IPs).

No source code, no file paths, no environment variables, and no PII are sent. The install ID is a random opaque UUIDv4 generated locally.

A first-run notice prints to stderr (never stdout — stdout is the MCP JSON-RPC channel) with the disclosure and the opt-out instructions. The notice fires once per install and never again.

Opting out

Any of these three methods disables the install ID:

1. Set ENDIAGRAM_TELEMETRY=off as an environment variable (also accepts 0, false, no).
2. Create a file at ~/.endiagram/telemetry containing the word off.
3. Delete ~/.endiagram/install-id. (A new one is generated on next run unless option 1 or 2 is also set.)

When any of these is active, the X-Endiagram-Install-Id header is not sent at all — the server falls back to its per-IP HMAC cid for correlation, which works fine for short-term per-session tracing.

Full privacy policy: endiagram.com/privacy

License

MIT