torno

[!NOTE] torno is new and early. It is developed on Linux (Arch, Wayland) 100% using claudecode and also runs on macOS, which has seen less use. Expect rough edges, and please open an issue when you find one.

Why torno

Coding agents are good at writing build123d models, the Python CAD library on top of OpenCascade. Two things get in the way. The agent can't see what it made, and it's hard for you to tell it which face is wrong, or by how much.

torno fixes both. It runs Claude Code next to a live 3D view of the model. You pin a note to a face, measure a wall or draw on the view, and the agent gets exactly what you pointed at: the face's ref, the exact measured value, your note. The agent also gets tools to look at the model, measure it and cut sections through it, so it can check its own work before it hands it back.

torno is not a modeller. It has no sketcher, no feature tree and no way to edit a solid by hand. The model is the Python file, and torno shows it.

Features

• Live builds. Every save rebuilds the model and redraws it. When a build fails, the last good parts stay on screen and the traceback is one click away. A failed fillet tells you which edges and what radius would work.
• Point, don't describe. Pins, arrows, strokes, shapes and picks on faces and edges, each with a note. The agent gets them with your next prompt as refs like lid/F12, never as vague words.
• Exact numbers. Distances, angles, radii and wall thickness are measured on the B-rep, not on the mesh. Give a dimension the value it should be and it says passes or fails after every build.
• The agent sees what you see. The agent gets MCP tools of its own: look (a picture of your view, marks included), measure, section, check (overlaps and printability), diff between builds, try_fillet and more.
• Section, explode, saved views. Cut through the parts, pull an assembly apart, keep a camera under a name.
• Scans. Import a phone or scanner mesh of the place the part has to fit, align it, and check clashes and deviation against it. torno always marks scan numbers as approximate.
• Start from what you have. A new project can start from a description, photos, doodles, scans and other projects in the workspace. Claude gets all of it with its first prompt.
• Export. A single HTML file anyone can open in a browser without installing anything, or STEP, STL and 3MF, a PNG of the view, and an SVG or PDF drawing of a section at true scale.
• Local. torno itself uploads nothing. The agent is your own claude, under your own login, and torno leaves its settings alone. In your folders, torno writes only under <project>/.torno/.

What goes well, and what does not

It goes well with prismatic parts that have sizes you measured: brackets, enclosures, holders, a lid and a box, hole patterns. It needs more from you for a part that must fit a place you can only scan, and for an assembly of more than three or four parts that touch. It does not go well with organic shapes described in words alone, gears and threads written by hand, or sizes read from a photo. Whatever the part, give a measured number, a scan or a dimension mark in place of a description. The manual has the lists.

How it works

A workspace is a folder of projects. Each project is a folder with one build123d model in it:

projects/
├── bracket/
│   └── bracket.py
└── hollow/
    └── hollow.py

A model gives its parts as a dict, or as make_<part>() functions, or as module-level shapes:

from dataclasses import dataclass
from build123d import Box, Cylinder, Pos

@dataclass(frozen=True)
class Params:
    side: float = 40
    wall: float = 2

def assembly(p):
    inner, height = p.side - 2 * p.wall, p.side - p.wall
    tub = Pos(0, 0, height / 2) * Box(p.side, p.side, height)
    tub -= Pos(0, 0, p.wall + inner / 2) * Box(inner, inner, inner)
    tub += Pos(0, 0, p.wall + 10) * Cylinder(3, 20)
    lid = Pos(0, 0, height + p.wall / 2) * Box(p.side, p.side, p.wall)
    return {"tub": tub, "lid": lid}

The app is Electron and three.js. The kernel is a Python package that loads models and tessellates them in forked workers. Each project gets its own Claude Code session, in the project's folder, connected to torno's MCP server on 127.0.0.1. See Projects and builds for the full rules.

Getting started

Requirements

• Linux or macOS (not Windows: the launcher, the terminal view and the login-shell PATH are for Unix; WSL2 is untried)
• Node.js 22.12 or later, and pnpm 10
• uv (it fetches Python 3.11 or 3.12 if you have neither)
• Claude Code (claude) on your PATH, logged in

torno checks all of this on its first screen, under "Ready to work", and says what's missing. The first build sets up torno's own Python environment with build123d and bd_warehouse (about 900 MB, once). If your workspace has its own pyproject.toml, torno uses that environment instead and never changes it. Run uv sync there once yourself. More in Requirements.

Install

git clone https://github.com/luisg0nc/torno.git
cd torno
pnpm install

Run

scripts/torno ~/projects    # open a folder as the workspace
scripts/torno               # the workspace you opened last, or the first screen

The launcher rebuilds the app when the sources change, so git pull and run it again. On the first screen, Open the example opens a small project, an enclosure with its brief and a few marks, in a temporary copy, so you can try everything without touching your own files.

以上为 README 的开头部分。其余内容请阅读原文。 查看完整 README ↗