---
name: markdownto-epub
description: Author, repair, validate, and review portable epub documents and their rendered results.
---
# Working with epub
Use this skill when the user wants the epub workflow. Read [SPEC.md](SPEC.md), then [shared conventions](../conventions.md). Published equivalents live at https://markdownto.ai/specs/epub.md and https://markdownto.ai/specs/conventions.md. The spec and fixtures govern conformance; this editorial guidance is non-normative and adapts to the user's brief.
## Author and repair
Confirm the purpose from the request, inspect any supplied references, and preserve supplied content and constraints. Start from a relevant valid fixture, not a remembered grammar. Write the envelope and meaningful `##` sections, then sparse direction. Avoid invented IDs. Run `mdto validate file.md` after edits. Repair diagnostics at their reported location using the spec's rationale; preserve unrelated source. Prefer the spec-owned verbs for state changes and preview their diff when useful. If the CLI is unavailable, perform a clearly labeled manual check against the spec and do not claim tool validation.
## Editorial judgment
Shape a book with an intelligible chapter arc and descriptive navigation. Establish the intended reader, assumed background, and what the reading should enable. Preserve the user’s voice and sources; do not invent authors, citations or illustrations. Use semantic headings rather than typography tricks. Tables should remain narrow enough for a phone; prefer prose for large comparison grids. Provide image descriptions and a cover suited to a thumbnail. Keep links meaningful out of context. Inspect the generated archive, chapter XML, contents links, image packaging and metadata, then read it at narrow width with enlarged type. Verify no text disappears when fonts or reading width change. Validate factual and editorial quality separately from package validity.
## Review and delivery
Use `mdto render file.md` and the spec's build or review verbs. Inspect the actual resulting interface or artifact, including mobile/narrow views, keyboard controls and content extremes. Verify state-changing UI actions against the same CLI operations. Deliver the Markdown and usable output, explain any real limitation, and never equate a valid file with a successful artifact review. If artifact inspection is unavailable, say which checks remain undone.
Give this guide to your agent, or read it as an author. It covers workflow and editorial judgment; the specification defines conformance.
Use this skill when the user wants the epub workflow. Read SPEC.md, then shared conventions. Published equivalents live at https://markdownto.ai/specs/epub.md and https://markdownto.ai/specs/conventions.md. The spec and fixtures govern conformance; this editorial guidance is non-normative and adapts to the user's brief.
Author and repair
Confirm the purpose from the request, inspect any supplied references, and preserve supplied content and constraints. Start from a relevant valid fixture, not a remembered grammar. Write the envelope and meaningful ## sections, then sparse direction. Avoid invented IDs. Run mdto validate file.md after edits. Repair diagnostics at their reported location using the spec's rationale; preserve unrelated source. Prefer the spec-owned verbs for state changes and preview their diff when useful. If the CLI is unavailable, perform a clearly labeled manual check against the spec and do not claim tool validation.
Editorial judgment
Shape a book with an intelligible chapter arc and descriptive navigation. Establish the intended reader, assumed background, and what the reading should enable. Preserve the user’s voice and sources; do not invent authors, citations or illustrations. Use semantic headings rather than typography tricks. Tables should remain narrow enough for a phone; prefer prose for large comparison grids. Provide image descriptions and a cover suited to a thumbnail. Keep links meaningful out of context. Inspect the generated archive, chapter XML, contents links, image packaging and metadata, then read it at narrow width with enlarged type. Verify no text disappears when fonts or reading width change. Validate factual and editorial quality separately from package validity.
Review and delivery
Use mdto render file.md and the spec's build or review verbs. Inspect the actual resulting interface or artifact, including mobile/narrow views, keyboard controls and content extremes. Verify state-changing UI actions against the same CLI operations. Deliver the Markdown and usable output, explain any real limitation, and never equate a valid file with a successful artifact review. If artifact inspection is unavailable, say which checks remain undone.