┌─────────────────┐     stdio      ┌──────────────────┐     TCP/JSON-RPC    ┌──────────────────┐
│   AI Assistant   │ ◄────────────► │  MCP Server (TS) │ ◄──────────────────► │  Civil 3D Plugin │
│ (Claude, Cline)  │               │   3 meta-tools    │     port 8080       │  Roslyn Engine   │
└─────────────────┘               └──────────────────┘                      └──────────────────┘
                                         │                                         │
                                    Skills Library                           C# Code Execution
                                   (.skill.md files)                      (full Civil 3D API)

User: "What surfaces are in my drawing?"

AI: Uses civil3d_query with:
  var surfaces = new List<object>();
  foreach (ObjectId id in CivilDoc.GetSurfaceIds()) {
    var s = Transaction.GetObject(id, OpenMode.ForRead) as TinSurface;
    surfaces.Add(new { s.Name, s.Layer });
  }
  return surfaces;

Result: [{ "Name": "EG", "Layer": "C-TOPO-EG" }, ...]

skills/
├── surfaces/           # Surface operations
├── alignments/         # Alignment + station/offset
├── points/             # COGO points
├── geometry/           # Lines, polylines, text
├── corridors/          # Corridor listing and info
├── pipe_networks/      # Pipe network listing and details
├── parcels/            # Sites and parcels
├── profiles/           # Profile listing and elevation queries
├── sections/           # Sample lines and cross-sections
├── labels/             # Label style inventories
├── styles/             # Object style inventories
├── export/             # CSV, LandXML export patterns
├── quantity/           # Volumes and corridor quantities
├── drawing/            # Drawing info
└── workflows/          # Multi-step civil engineering workflows

npm run setup

# Option A — pass the path directly
npm run setup -- -InstallPath "D:\Program Files\Autodesk\AutoCAD 2026"

# Option B — environment variable (picked up automatically during scan)
$env:CIVIL3D_INSTALL_PATH = "D:\Program Files\Autodesk\AutoCAD 2026"
npm run setup

# Option C — interactive: when the menu appears, press C and paste the path
npm run setup

npm install && npm run build

# References are in plugin/Civil3dMcpPlugin/Civil3dMcpPlugin.References.props
# Regenerate with: npm run setup
# Custom install path: npm run setup -- -InstallPath "D:\...\AutoCAD 2026"
cd plugin/Civil3dMcpPlugin
dotnet build

NETLOAD → select Civil3dMcpPlugin.dll
C3DMCPSTATUS → verify running

{
  "mcpServers": {
    "civil3d": {
      "command": "node",
      "args": ["/path/to/civil3d-mcp/build/index.js"]
    }
  }
}