Guide for modifying USD ASCII (.usda) files, including prims, properties, composition arcs, variants, and transforms. Use when editing or reviewing .usda files by hand.
Use this skill for minimal, text-level USD or USDA edits and command-line USD inspection, conversion, packaging, rendering, and validation. Keep the change small and preserve existing composition unless the task explicitly says otherwise.
When authored Reality Composer Pro or USD content owns the scene, geometry, transform, animation, or material, keep that authored surface as the source of truth. Use Swift and RealityKit to load or adjust runtime state; do not recreate authored USD content in Swift unless the request is explicitly procedural.
If Swift code needs to open, edit, observe, or export stages in-process with
USDStage, USDPrim, or USDLayer, switch to $usdkit-runtime-developer.
If the change is material- or shader-specific for RealityKit, prefer
shadergraph-editor.
| Reference | When to Use |
|-----------|-------------|
| usd-syntax | When you need a refresher on .usda syntax, values, and path formats. |
| prims-properties | When adding or editing prims, attributes, or relationships. |
| composition-variants | When touching sublayers, references, payloads, or variant sets. |
| transforms-units | When editing transforms, xformOps, or stage units and up-axis metadata. |
| time-samples | When modifying animated or time-sampled properties. |
| command-line-tools | When you need a quick reference for common USD command-line tools. |
| usdcat | When converting, flattening, or inspecting USD files. |
| usdchecker | When validating USD or USDZ assets, including RealityKit-focused checks. |
| usdrecord | When rendering images from USD files. |
| usdtree | When inspecting the prim hierarchy of a USD file. |
| usdzip | When creating or inspecting USDZ packages. |
| usdedit | When you need the official text-editing workflow for a USD-readable file. |
| visionos-runtime-loading.md | When the question is how authored USD or USDZ actually loads and behaves in a visionOS app. |
| apple-runtime-boundaries.md | When deciding whether to edit authored USD / Reality Composer Pro content, load it through RealityKit, or validate it for Apple platforms. |
usdtree, usdcat --loadOnly, or usdcat --flatten
before editing, depending on the risk.over, def, or a list edit deliberately.usdchecker --arkit for shipping visionOS USDZ assets.def when over is the correct edit.Entity(named:in:),
Entity(contentsOf:withName:), or a generated Reality Composer Pro content
bundle, prefer fixing the authored asset and validating the bundle/package
over building a parallel Swift scene graph..usdz package in place; inspect or unpack it, edit the
source layer, rebuild the package, and validate the result.usdchecker --arkit --strict,
not just a source-layer parse check.Provide:
$usdkit-runtime-developer, shadergraph-editor, or runtime
testing if neededSearch for places (restaurants, cafes, etc.) via Google Places API proxy on localhost.
Interact with GitHub using the `gh` CLI. Use `gh issue`, `gh pr`, `gh run`, and `gh api` for issues, PRs, CI runs, and advanced queries.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Start voice calls via the OpenClaw voice-call plugin.
Notion API for creating and managing pages, databases, and blocks.
Gemini CLI for one-shot Q&A, summaries, and generation.
Category:developer