explain-with-preview

Explain with Preview

A two-column chapter: a short framing sentence and a few clickable cards on the left, and a sticky panel on the right that switches when the reader picks a card. Switching back and forth makes the differences obvious.

Use this skill when

• The user asks for a visual explanation of changes with a preview.
• Used by an orchestrator to explain changes visually with a preview.

Two modes

Mode	Cards	Starts on
Options (decision)	One per option, 2–3, including a cautious / low-risk one	The recommended option
Before / after	Exactly two: "Before · today" and "After · with the change"	After ("selected")

Content

• Every option has the same rows in the same order so only the differences change: for a decision usually Keeps (ok), Loses (removed), Fix first (decision, concrete actions), Risks (risk), plus effort (hours or days, and what the work is). 2–4 short items per row, real names and numbers from the facts: every finding that matters for that option belongs in one of its rows.
• Fragility, dependencies and complexity belong in these rows (e.g. "Fix first: port 3 path checks into the local plugin"), not in chapters of their own.
• Gloss a tool or term in the row where it first appears ("nursery (Biome's unstable rules)").
• code (optional per option): ≤ 8 real lines of the config or code that option adds or changes, with its file path. Give the recommended option one when the change is config or code.
• flip: what would change the recommendation (1–3 items). details: "How it was measured" (the commands, versions, machine, single or repeated runs, what was not measured) and "Sources" (links).
• Use real content. Label an illustration as one.

Build it from JSON

Write the chapter as JSON and generate the fragment; no HTML, CSS or script by hand:

python <explainer-kit>/assets/preview.py decide.json --out frag-decide.html

The JSON shape is documented at the top of preview.py and in the kit's FRAGMENT-CONTRACT.md ("Preview chapters from JSON"). Text fields may contain inline <b>, <code> and <a href>.