.agents/skills/scaffold-element/SKILL.md
The source of truth for design and quality criteria is the Element Guidelines. Read them completely before making changes. If this skill and the guidelines diverge on acceptance criteria, follow the guidelines.
This skill owns the technical scaffolding workflow. Use the publish-element skill when the Element is ready for the gallery.
Choose an existing category and a kebab-case slug. Before creating files, determine the initial preview metadata needed for development:
null for both so it inherits the composition dimensionsInspect packages/docs/elements-template/ and at least one existing Element in the same category. Do not create a new category unless the task explicitly requires one.
From the repository root, replace the placeholders and run:
cp -R packages/docs/elements-template \
packages/docs/elements/<category>/<slug>
mv packages/docs/elements/<category>/<slug>/element.tsx \
packages/docs/elements/<category>/<slug>/<slug>.tsx
Adapt the copied index.mdx to the production pattern: import elementDefinitions, use its '<category>/<slug>' entry, and set sourceFile="./<slug>.tsx".
Implement only enough of the component to provide a visible starting point in the intended bounds. Keep the reusable implementation in one self-contained TSX source file. Make the component fill its bounds without adding a wrapper <Sequence> or source padding for the preview. Do not use left, right, top, or bottom to place the Element itself; the surrounding project owns placement.
Follow the Element Guidelines for the component itself. When using Studio-editable controls, also follow the interactivity best practices skill. Keep entrance and exit keyframes inline with hardcoded frame ranges on the useful named Interactive.* element so they can be adjusted in Studio. Do not repeat the Element display name in inner control names.
Import and register the component in packages/docs/src/components/Elements/element-definitions.ts using the planned preview metadata.
Do not edit packages/docs/src/remotion/Root.tsx. It automatically creates a composition for every central definition using the same sizing and wrapper used by published Elements.
If the component imports a package that is not available to packages/docs, add it to packages/docs/package.json, run bun install, and include bun.lock.
Format the changed TypeScript and TSX files, then run the focused test:
bunx oxfmt \
packages/docs/elements/<category>/<slug>/<slug>.tsx \
packages/docs/src/components/Elements/element-definitions.ts \
--write
cd packages/docs
bun test src/test/elements.test.ts
cd ../..
Do not add the category-index or sidebar entries and do not render final preview assets yet. Those belong to the publishing workflow.
Do not launch the Studio from this skill. Tell the developer to run:
bun run build
cd packages/docs
bun run remotion
Then tell them to open the elements folder and select element-<category>-<slug>. Development should start in that composition so the Element is always evaluated with its configured dimensions, duration, padding, and preview background.
Report the created files, composition ID, focused test result, and that the next step after development is the publish-element skill.