CAD-Query Workspace MCP

Generate parametric 3D CAD models from natural language using CAD-Query via Model Context Protocol.

Overview

This skill enables conversational 3D modeling using an external CAD-Query MCP server. Generate parametric CAD models from descriptions, verify designs, and export STL files for 3D printing.

Prerequisites

Workflow

Step 1: Study Documentation

Before generating any CAD model, thoroughly review the documentation:

1. Read `docs/cadquery/classreference.md` for CAD-Query API methods

2. Read `docs/cadquery/primer.md` for core concepts

3. Read `docs/cadquery/examples.md` for modeling patterns

4. Study `examples/` directory for similar models to what you're creating

Use the Read tool to search documentation for specific techniques.

Step 2: Generate CAD Code

Use the `generate_cad_query` MCP tool with clear, detailed descriptions:

```python

generate_cad_query(

description="Create a coffee mug with a handle, 10cm tall and 8cm diameter, wall thickness 3mm",

parameters="height=100mm, diameter=80mm, wall_thickness=3mm, handle_width=15mm"

)

```

**Important Requirements:**

**Example Script Structure:**

```python

import cadquery as cq

result = cq.Workplane("XY").box(10, 10, 10)

show_object(result) # Required for MCP server

```

Step 3: Verify Model (CRITICAL)

**ALWAYS** verify generated models before presenting to users:

```python

verify_cad_query(

file_path="outputs/coffee_mug.py",

verification_criteria="coffee mug with handle, 10cm height, 8cm diameter, 3mm wall thickness"

)

```

**Never skip verification** - it ensures quality and correctness.

Step 4: Present Results

Only after verification passes:

1. Inform user of successful generation

2. Describe the generated model

3. Provide paths to output files:

- `{model_name}.py` - CAD-Query Python script

- `{model_name}.stl` - STL file for 3D printing

- `{model_name}.step` - STEP file for CAD software

Available MCP Tools

`generate_cad_query`

Generates CAD-Query Python scripts from natural language.

**Parameters:**

**Note:** Currently stub implementation - manually create scripts based on documentation and examples when needed.

`verify_cad_query`

Validates generated CAD models before presentation.

**Parameters:**

Key Documentation Files

Example Models Reference

Study these samples in `examples/`:

Best Practices

1. **Always study documentation first** - Review relevant docs before generating models

2. **Use clear descriptions** - Provide detailed, unambiguous descriptions to MCP tools

3. **Specify dimensions** - Include precise measurements and constraints

4. **Always verify** - Never present unverified models to users

5. **Reference examples** - Study similar models in `examples/` directory

6. **Follow script requirements** - End all scripts with `show_object(result)`

Common CAD-Query Patterns

Basic Shapes

```python

Box

result = cq.Workplane("XY").box(10, 10, 10)

Cylinder

result = cq.Workplane("XY").circle(5).extrude(10)

Sphere

result = cq.Workplane("XY").sphere(5)

```

Operations

```python

Boolean union

result = part1.union(part2)

Boolean subtraction (hole)

result = base.cut(hole)

Fillet edges

result = part.edges().fillet(1)

```

Revolve (for cylindrical objects)

```python

result = cq.Workplane("XZ").lineTo(10, 0).lineTo(10, 20).lineTo(5, 20).close().revolve()

```

Output Files Location

All generated files are saved to `outputs/`:

Constraints