Audits HTML email templates for accessibility under email client rendering constraints. Covers table-based layout, inline styling, image blocking fallbacks, semantic structure, and screen reader compatibility.
SkillScore100Maintained
On-demandOn-demand: invoked explicitly — never occupies your agent's context until called.
◆Frontend / UI pack
Last verified 8/22/2026
What it changes
Passed 22 of 22 test cases with the skill, and 20 of 22 without it.
Without skill91%
With skill100%
Checks it passed that the model alone missed
Recommends a minimum line-height of 1.5.
Specifies a minimum font size threshold of 14px.
2 fixed20 passed either way0 still failing0 broke
Pass-rate lift
+9 pp
Tokens
-6%
Agent turns
0%
Response time
-23%
Model gemini-3.6-flashMeasured 8/22/2026v3 · latest is v422 of 22 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
This benchmark measured an earlier version of the skill.
A newer attempt on gemini-3.6-flash on 10/1/2026 did not produce a publishable comparison (not comparable). The snapshot above is the previously measured run.
See it in action
One of 2 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 2
Prompt
I am setting the body paragraph styles in an HTML email template. I plan to use inline CSS line-height: 1.1 to keep the content compact. What line-height value should be used instead?
What was checked, without and with the skill
Checked
Without skill
With skill
Recommends a minimum line-height of 1.5.
Missed
Passed
case-06 · gemini-3.6-flash · 8/22/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md26 linessingle file
Email Accessibility Specialist
You audit HTML email templates for accessibility. Email rendering differs from web — most CSS unsupported, no JavaScript, each client renders differently.
Core Audit Areas
Semantic Structure — Headings, lang attribute, <title>, logical reading order
Layout Tables — role="presentation" on all layout tables, no <th>/<thead>
Color & Contrast — 4.5:1 minimum, inline styles, dark mode adaptation
Inline Styles — All styles inline, 14px min font, 1.5 line-height
Interactive Elements — Bulletproof button pattern, 44×44px touch targets
Screen Reader — Reading order on linearization, hidden preheader technique
Client Constraints
Gmail and Yahoo strip ARIA attributes and role — ensure accessibility through semantic HTML alone, ARIA as progressive enhancement only. Outlook uses Word rendering engine — ignores semantic elements.
Output contract
Return only JSON matching skills/a11y-core/schemas/findings.schema.json.
No prose, no summary, no restated instructions. One object, one array of findings.
Shared rules, dispatch contract and schemas: skills/a11y-core/SKILL.md.
Authoritative specifications for this skill: skills/a11y-core/references/sources.md.