cad-viewer

# CAD Viewer 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. If the user asks to modify, debug, or iterate on CAD Viewer source itself, clone that repository and work there — this installed skill runtime runs the Viewer, it is not where you edit it. Use this skill to open existing or newly generated CAD, implicit CAD, robot-description, or DXF files in CAD Viewer and hand back live review links. The expected input is one or more explicit file paths. ## Start Viewer Start one local CAD Viewer with `npm run start`. It serves the prebuilt Viewer bundle plus the CAD API on a single fixed port (`3245`). It is NOT started against a directory — a URL names the directory, so one Viewer serves any folder. > The default port `3245` is `0xCAD` — "CAD" in hexadecimal. Run from this skill directory: ```bash npm --prefix scripts/viewer run start -- --host 127.0.0.1 ``` ## URL shape A Viewer URL's **path is the absolute directory**, exactly as in a `file://` URL, and `file=` selects one artifact inside it: ```text http://127.0.0.1:3245/absolute/project/models?file=mechanisms/lift_table.step.py ``` **Always build the path from an absolute directory.** The Viewer runs from an arbitrary working directory — usually wherever the skill happens to be installed, not the model directory — so a relative path resolves against the wrong place. The `file=` value is relative to that directory. **On Windows the drive goes in the path, after the URL's leading slash**, with forward slashes: `D:\project\models` is `http://127.0.0.1:3245/D:/project/models`. The launcher prints this form already; build it the same way by hand. **The path is the workspace, not the file's folder.** The Viewer scans it recursively, so the file browser lists every model beneath it and the user can switch files without a new link. Pick the directory the user thinks of as their model workspace — typically the project's `models/` directory, or the nearest common parent of the files you were asked to review — and put the rest of the path in `file=`. Naming the artifact's own deep folder (`.../models/step/mechanisms?file=lift_table.step.py`) opens the same model but hides the rest of the project, which is almost never what the user wants. If port `3245` is already in use, the launcher exits with an error rather than rolling to another port; rerun with an explicit free port, `--port <n>`, and use the URL it prints. In sandboxed agent environments, local binding failures such as `EPERM`/`EACCES` can be expected; rerun with the needed permission/escalation. Add `--json` to also print a machine-readable result as the last stdout line beginning with `{` (`{"url": ..., "port": ..., "action": "start"}`). The printed URL points at the launch directory; replace its path to review any other folder. ## Links - Before returning any link, resolve `<directory>/<file>` and confirm it exists. For a **generated** model pass the generator source (`<name>.step.py`) — that is what the catalog itself lists, the backend resolves it directly and builds the render artifacts on demand, and no `.step` file needs to exist. It is also the only form that carries a `params` sidecar, because a same-stem `<name>.step.py` shadows `<name>.step` anyway. For an **imported** STEP with no generator, pass the `.step`/`.stp` itself. If the resolved path is missing, do not return the link; report the problem and point to the correct path. - Return one Viewer URL per requested file. - Start the Viewer once and pick one workspace root for the session. Every link is that same absolute root plus `?file=<path relative to it>`, so all of them share one browsable catalog. Only use a second root for an artifact that lives outside the first. - For directory-only review links, return the directory URL without `?file=`. - Do not stop an existing Viewer server unless the user asks. - If Viewer startup fails, report the failure and continue with the owning skill's non-GUI validation or artifacts. ## References - Read `references/viewer-features.md` when you need supported file types, Viewer controls, or file-specific feature details. - Read `references/moveit2-server.md` only when the user specifically needs optional SRDF MoveIt2 IK or path-planning controls.