sdf

# SDF Provenance: maintained in [earthtojake/text-to-cad](https://github.com/earthtojake/text-to-cad). Use the installed local skill files as the runtime source of truth; the repository link is only for provenance and release review. Use this skill when the deliverable is an SDFormat document. SDFormat describes simulator and world behavior: models, worlds, frames, poses, links, joints, inertials, visuals, collisions, sensors, lights, physics, plugins, includes, and simulator metadata. This skill is for **SDFormat**, not signed-distance-field geometry. The `.sdf` file is the source of truth: author and edit the XML directly. There is no `gen_sdf()` contract. ## Setup This skill's commands are thin entrypoints over the `cadgen` distribution, which carries the Python build runtime and the JavaScript it executes. Install it once: ```bash python -m pip install -r requirements.txt ``` Rendering additionally needs a browser, which pip cannot supply: ```bash python -m playwright install chromium ``` ## Core rules 1. Author `.sdf` XML directly and validate every created or modified file with `cadgen sdf validate` before reporting completion. 2. Identify the target consumer before editing: Gazebo/libsdformat version, another simulator, visualization-only tooling, model package, or world handoff. 3. Decide document kind: model-level SDF, world-level SDF, or model-in-world. Prefer model-level SDF for reusable robot/object exports. 4. Use SI units unless the target explicitly ...