HTML Artifact

Create a self-contained HTML document for human reading or interaction. Use it when explicitly requested or when a standalone visual materially helps explain, compare or explore the content. A report, plan or one-pager alone is not a trigger. Keep agent instructions, source documents and Markdown-native deliverables in Markdown; brief inline explanations need no HTML scaffold.

Artifact contract

• One file with inline CSS/JS, viewport metadata and no build step. Work offline from a local file: no external fonts, trackers, API fetches or runtime assets.
• Semantic markup, keyboard access and adequate contrast. Layout adapts to narrow screens; honor reduced motion for animation and provide readable print styles.
• Explanatory content exists before scripts run. With JS disabled, preserve the explanation, data and limitations even when interactive computation is unavailable.
• Use project visual conventions where compatible with this contract. Show only sourced data; label assumptions and illustrative values explicitly.

Choose the shape

Select the matching preset when its layout helps:

Main purpose	Reference
Narrative report or comparison	references/preset-report.md
Charts carry the argument	references/preset-dashboard.md
Teach a concept	references/preset-explainer.md
User edits values or copies a configuration	references/preset-editor.md

For an unfamiliar figure, consult references/svg-craft.md; for optional default styling/components, use references/visual-style.md. Read only relevant sections, and do not invent content to satisfy a preset. Prefer a simpler shape when it communicates the source faithfully.

Deliver and verify

Use the supplied output location, otherwise a descriptive file under scratchpad. Provide a link/path rather than pasting HTML source. Check content fidelity and local links, then exercise key interactions and responsive/print behavior using available browser tools. Inspect JS-disabled readability and motion settings when relevant. Report checks that could not run; do not automatically assign them to the user. Name material omissions or transformations when condensing a source.