Open-Source Text-to-CAD Plugin for Codex: From STEP Generation to DFM Validation and Bambu Lab Fabrication

Explore text-to-cad, an open-source local plugin for Codex that generates parametric STEP, STL, 3MF, and GLB models from natural language and images, featuring

tau · October 4, 2026

#TextToCAD #Codex #3DCAD #DFM #OpenSource #BambuLab #SendCutSend

Open-Source Text-to-CAD Plugin for Codex: From STEP Generation to DFM Validation and Bambu Lab Fabrication

On October 3, 2026, Jake Fitzgerald (@earthtojake) officially released text-to-cad, an open-source plugin that enables developers to generate 3D CAD models and validate manufacturing readiness locally inside coding agent desktop environments. Distributed free of charge via GitHub (earthtojake/text-to-cad), the plugin is powered by the Python geometry engine cadgen and the Open CASCADE (OCP) kernel.

text-to-cad open-source 3D modeling and DFM inspection interface running inside the Codex desktop app

Image source: Jake Fitzgerald (@earthtojake)

Unlike conventional text-to-3D models that primarily output mesh approximations unsuitable for precision engineering, text-to-cad focuses on industry-standard STEP solid models. It integrates a complete workflow covering parametric solid generation, process-specific Design for Manufacturing (DFM) analysis, slicer orchestration, and direct fabrication handoffs.

1. STEP-First Parametric CAD Generation and Built-in 3D Viewer

text-to-cad transforms natural language instructions or reference 2D drawings and images into parametric B-Rep solid geometry.

  • Standard Engineering Formats: Generates dimensionally accurate STEP (.step, .stp) models as primary outputs, with one-click export support for STL, 3MF, and GLB meshes.
  • Parametric Source Control: Dimensions, hole placements, chamfers, fillets, and assembly joints are managed programmatically, making geometric iterations and adjustments straightforward.
  • Integrated Codex CAD Viewer: Installing the plugin adds a dedicated 3D CAD viewer tab to the Codex sidebar and thread view. Users can rotate, zoom, and inspect cross-sections in real time, while the agent can detect user selections to guide subsequent revisions.

2. Automated DFM Inspection Across Four Core Processes

To mitigate physical defects and manufacturing failures prior to production, the plugin embeds automated DFM rulesets. Adding /dfm to a prompt or requesting an inspection triggers detailed geometric measurements against established manufacturing tolerances:

  • 3D Printing (DfAM): Analyzes minimum wall thickness, overhang angles, support-required geometries, and optimal build orientations for FDM, SLS, and SLA workflows.
  • Sheet Metal: Checks bend radii, hole-to-edge clearances, and slot spacing against material thickness.
  • CNC Machining: Evaluates tool reachability, pocket depth-to-corner radius ratios, and undercut occurrences.
  • Injection Moulding: Calculates draft angles, undercut regions, and projected surface areas for mold parting.

3. Direct Fabrication Handoffs: SendCutSend and Bambu Lab

Beyond modeling, the plugin bridges digital CAD designs directly to physical fabrication and manufacturing services:

  • SendCutSend Preflight: Evaluates DXF and STEP files against SendCutSend service guidelines and material catalogs, verifying compatibility for laser cutting, CNC routing, bending, and tapping.
  • Bambu Lab 3D Printing: Orchestrates local slicer CLIs to generate validated FDM .gcode, with automated dry-runs and job uploads via Bambu LAN FTPS/MQTT, Bambu Connect, or Bambu Studio.

4. Installation and Practical Considerations

The text-to-cad plugin requires Codex version 0.142.0 or newer and relies on uv for local runtime resolution.

# Register marketplace and install plugin in Codex
codex plugin marketplace add earthtojake/text-to-cad
codex plugin add text-to-cad@earthtojake

# Quit and restart Codex app

Key technical considerations for current workflows include:

  • Organic Geometry Development: The tool is currently optimized for prismatic and mechanical engineering components. Complex organic curved geometries are actively in development under an organic-cad pull request.
  • Pre-Production Review: While automated DFM checks catch common rule violations, visual inspection of dimensions and sliced toolpaths in the local viewer remains recommended before committing to high-cost machining or batch printing runs.
  • Expanding Client Support: Alongside Codex desktop integration, setup paths for Claude Code, Claude Desktop, and Cursor are actively expanding.

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