export-diagram

---

description: Export a diagram-design HTML file to .svg and .png next to the source argument-hint: [--svg-only|--png-only] [--scale=N] [--output=] [--registry] allowed-tools:

• Read
• Write
• Edit
• Bash
• Glob

---

Export the diagram HTML at $1 to .svg and/or .png, following the procedure documented in skills/diagram-design/references/export.md. Treat that reference as the source of truth — don't reimplement the logic here. If --registry is present, also follow skills/diagram-design/references/export-registry.md to emit the metadata sidecar — a separate procedure from the SVG/PNG rasterization above.

Full argument string: $ARGUMENTS

Defaults

• With no format flags, or with --svg-only/--png-only/--scale/--output but no --registry: produce both .svg and .png next to the source (e.g. diagram.html → diagram.svg + diagram.png).
• PNG renders at device_scale_factor=2.
• --registry given by itself, with neither --svg-only nor --png-only also present, produces only the registry JSON. The SVG/PNG defaults above do not also apply, and Playwright is never required for a registry-only call. To get an image alongside the registry, add --svg-only and/or --png-only explicitly.

Flags

• --svg-only — emit only the SVG. Skip Playwright entirely.
• --png-only — emit only the PNG.
• --scale=1 / --scale=2 / --scale=3 — override the PNG device scale factor. Default 2.
• --output=<path> — override the output base path; the format extension is appended. Applies to both formats when both are produced.
• --registry — emit <basename>.registry.json, a metadata sidecar of every block's data-block-* attributes. Follows skills/diagram-design/references/export-registry.md, a procedure independent of the SVG/PNG rasterization above — it never needs Playwright. Used alone (see Defaults), it is the only output produced. Combine with --svg-only and/or --png-only to also produce an image in the same call.

Required behaviour

1. No source path provided → ask the user which .html file to export. Don't guess.
2. Source is assets/index.html (the gallery, multiple SVGs in one file) → refuse and ask which specific diagram file. Per the reference's edge-case section.
3. Source has no <svg> block → refuse and tell the user; don't write anything.
4. PNG requested but Playwright not installed → surface the install instruction from the reference verbatim and stop. Do not auto-install.
5. PNG requested with --scale outside {1,2,3} → reject; valid values are 1, 2, 3.
6. --registry requested but source has no data-block-id attributes → refuse and tell the user; don't emit an empty or partial registry file. Per the export-registry reference's edge-case section.
7. --registry is the only flag given (no --svg-only/--png-only) → emit only the registry JSON. Do not also produce SVG/PNG, and do not check for Playwright — a registry-only call must succeed on a host that doesn't have it installed at all.

After producing the outputs, report the file paths and sizes back to the user.