Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add zenitheditor/zenith --skill html-authorgit clone --depth 1 https://github.com/zenitheditor/zenithWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/zenitheditor/zenith/html-author)<a href="https://agentmods.dev/skills/zenitheditor/zenith/html-author"><img src="https://agentmods.dev/badge/skills/zenitheditor/zenith/html-author/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/zenitheditor/zenith/html-author"><img src="https://agentmods.dev/badge/skills/zenitheditor/zenith/html-author.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00070 | $0.00242 |
| Opus 5.5 | $0.00028 | $0.00097 |
| Sonnet 5.5 | $0.00014 | $0.00048 |
| Haiku 4.5 | $0.00007 | $0.00024 |
Grade A, and why
html-author scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
HTML design authoring
Build the whole design in one file at the canvas size the task gives. Write the file once, then refine it.
Read references/authoring.md before the first write.
- Decide the hierarchy first: what is read first, second, and last. Size and weight carry it.
- Write
design.htmlwith every page as a fixed-size section. Put colors, sizes, and spacing in CSS variables at the top. - Lay out with flex or grid inside each page. Use absolute positioning only for decoration.
- Render with
viewand check each page. - Fix what the render shows: cramped or cut-off text, weak contrast, uneven spacing, empty regions.
- Stop when every page reads clearly. Reply with one short sentence.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 4d ago First seen · 18 lines · 70 tokens per session scan A 7c18dafbe5cd
html-author is a skill published in the GitHub repository zenitheditor/zenith (22 stars, last pushed 4d ago), licensed Apache-2.0. It adds 70 tokens to every session and 242 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-10-12.
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