# Laser Lightburn > Write LightBurn `.lbrn` project files, and deliver cut settings as text for a job the user drew themselves. Use when a laser test card or job file has to be generated, when a question is about the `.lbrn` format or what LightBurn does with an element, or when layer parameters must be handed over for typing into LightBurn's cut settings. A service to `laser-machines`: it holds no opinion about materials and runs no dialogue about what to engrave. - Skill: `robustagile/laser-lightburn` (Agent Skill, multi-file: 25 files) - Install (CLI): `npx skillmds@latest add robustagile/laser-lightburn` - Raw SKILL.md: https://api.skillmd.com/api/skills/robustagile/laser-lightburn/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: robustagile (https://skillmd.com/u/robustagile) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/robustagile/laser-lightburn --- # LightBurn file generation TODO: one paragraph - the mechanics half. Given a machine record and a card or job specification, produce a `.lbrn`. LightBurn v2 is the only target (R-E1). ## Never emit an element that has not been read back in LightBurn's UI TODO: the one rule that must never be missed. LightBurn silently normalises what it does not recognise - an invented layer type was loaded, rewritten as a plain one, and its contour dropped, with no error. The `doOutput` case (R-G15) is why this is a hard rule: guess it wrong and a layer meant as a guide fires the laser. Verified versus assumed is `references/lbrn-format.md`; nothing from the assumed column may be emitted. ## "It opens" is not verification TODO: nor is a round-trip diff - LightBurn v2 rewrites the file on save whether or not it understood an element. Verification is visual or measured in the UI. An inferred constant must not be asserted by a test built on the same inference. ## Prerequisite: the .NET SDK TODO: R-N8 - checked here on first use, not by the installer, because a .NET program cannot check for .NET. Platform-specific guidance when it is missing. ## Where files are written TODO: R-G4 and OQ-9 - the output directory is a `config.md` setting pointing at a path LightBurn can open, which on this setup means Windows-visible while the agent runs in WSL. Generated files are write-only and disposable: re-run the generator, never re-read a saved file (R-G3). ## What the writer can emit today TODO: shapes, layers and sub-layers, live text, transforms, arrays. And what it cannot: no bitmap shape, no verified `Image` layer, so nothing raster (R-G16), which blocks the `photo-marking-*` catalogue entries and depth maps (R-G17). ## Building and running the generator TODO: the projects under `tools/`, how they are built on first use, and how they are invoked. ## The job specification TODO: the JSON handed to the generator. `design-data-formats.md` ยง7. ## Reading the machine record Field size, spot size and the frequency ceiling come from the machine record, not from the conversation (R-G10). It is where `laser-machines` put it, and that location is **derived, never searched for**: this skill is installed at `/skills/laser-lightburn/`, where `` is a `.claude` directory, and the store is that directory's sibling `/../laser-skill-data/`. So the record is `/machines/.md` and the recipes are under `/recipes///`. Resolve it once from the path this file was loaded from. It sits outside `.claude/` on purpose - Claude Code guards writes in there, and a settings rule does not lift the guard. Do not `find` for the store, do not sweep the home directory, and do not read the plugin's development clone even when this skill directory is a symlink into one (R-N4). If the record is not there, nothing here can be generated: a card or a job needs a field size it must not invent. Say which machine is missing and hand back to `/laser-machine`. TODO: which fields each kind of output needs, and what to do when one of them is still unknown in the record. ## Test cards TODO: -> `references/test-cards.md`. ## Jobs TODO: -> `references/jobs.md`. Two modes, neither a fallback of the other (R-W3.4). ## Mode 2 - parameters as text, not a file TODO: R-W3.5 to R-W3.7. Fields named and united as LightBurn's UI names them; every value the user must type is present, including one deliberately left at a default; provenance and acceptance criteria travel with the numbers. A geometry-free `.lbrn` is rejected outright. `.lbset` is v2 - deferred, not rejected, so nothing here may foreclose it. ## Reference files TODO: the table - what each file is for and when to read it.