Typography check

Rules from the Typography Handbook web edition and its print edition, with thresholds and fixes. The medium decides the rules: 10pt justified text in absolute leading is correct in a book and wrong on a web page. Identify the medium before judging anything.

1. Identify the medium

• Mixed file: split it by context. Rules inside @media print and @page get the print rules; everything else gets the web rules. Report the two as separate sections.
• Office/screen PDF at a book or magazine size: it is probably a proof heading to press. Ask.
• No signals, or conflicting ones: ask one question before reviewing: "Where will this be read: in a browser, printed (press or office printer), or as a PDF on screen?"

Write the medium and the evidence for it on the first line of the report.

2. Measure, don't guess

Then look. Numbers find candidates; the eye decides alignment. An optical correction (display type pulled left of the column edge, a label set off its box's geometric center, a round icon drawn larger) departs from the measurement on purpose, and it is right when the result looks aligned.

• Don't report a measured offset as a fault when it is an optical correction. Signals: a negative margin or indent in em on display type, text-box trimming, asymmetric padding repeated across a component, a token or comment naming the nudge. Name it under "Already right".
• Report an offset that looks accidental with its measured value and what it looks like on the render.
• Optical judgment overrides geometry (positions, alignment, relative sizes), never accessibility thresholds. Contrast, minimum sizes and zoom stay numeric.
• The optical rules in shared.md need a render. In a static review, say they were not checked.

3. Load the rules

• Always: references/shared.md (hierarchy, proximity, paragraphs, fonts, characters, micro-typography).
• Web: references/web.md, including its APCA section.
• Print, print stylesheet or press PDF: references/print.md. Read its "Web habits that are wrong in print" table before reporting any print finding.
• PDF: references/pdf.md, plus print.md for press PDFs.

4. Report

Use this shape:

## Typography check: <target>
Medium: <web | print | web + print stylesheet | press PDF | screen PDF> (<evidence>)
Basis: <measured with extract-web-type / inspect-pdf | static review, rendered font not verified | visual estimate>

### P0 broken
- `rule-id` <location: file:line, page, or role>: <issue, with the measured value>. Fix: <the concrete change>.
### P1 readability / accessibility
### P2 craft
1. `rule-id` <location>: <issue>. Fix: <change>.
2. …
### P3 polish
3. … (numbering continues from P2 and stops at 10)
Also worth a look: `rule-id` (location), `rule-id` (location), …

Already right: <one line naming what is correct, deliberate optical corrections included, so nobody "fixes" it>

• Every finding has a rule ID, a location, the measured or declared value, and a concrete fix (CSS, a setting, or a corrected character).
• Write out every P0 and P1 finding in full.
• Number the written-out P2 and P3 findings 1 to 10 across both headings, choosing the most visible ones. Finding 11 and beyond go on the single "Also worth a look" line as a rule ID and location only.
• Each finding takes the severity given in its rule table. Don't move one down to tidy the list.
• Leave out empty severity headings.
• The check covers typography only: type, fonts, spacing of text, color of text, page and production as they affect type. Anything else gets at most one closing line, "Outside typography: …", or nothing.

Gotchas

• Character rules apply only to rendered copy. Never "fix" quotes or -- inside <code>, <pre>, string literals or CLI flags.
• Check the font before flagging an OpenType feature. A font-variant-* or font-feature-settings fix does nothing if the face lacks the feature.
• Declared is not rendered. A web font that 404s, or a print font that isn't installed, silently becomes the browser default or Times. Check roles[].font.likely or structure.fonts, and report a substitution as P0.
• Dark-mode weight goes up, not down. Light-on-dark text looks thinner, so dark mode needs web/dark-weight.
• Check every color scheme and every button. A gray that passes on white can fail on the dark background, and the reverse.
• WCAG 2.x is the compliance check; APCA is a second opinion. Report both numbers when they disagree, following web.md.
• Use fewer thresholds and more evidence. "116 characters per line at 22px (web/measure, 45–75)" is a finding. "The lede feels long" is not.
• An audit is not a redesign. Propose fixes inside the existing type system. A new pairing or scale only if the user asks.

Sources and credits

• Rules paraphrased from Typography Handbook (2026 edition, based on Kenneth Wang's original, MIT).
• Report shape and the code-literal and OpenType cautions follow mblode/agent-skills typography-audit (MIT).
• APCA constants are from the APCA-W3 0.0.98G reference.