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 NickCrew/Claude-Cortex --skill html-seo-reviewgit clone --depth 1 https://github.com/NickCrew/Claude-CortexWrote 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/nickcrew/claude-cortex/html-seo-review)<a href="https://agentmods.dev/skills/nickcrew/claude-cortex/html-seo-review"><img src="https://agentmods.dev/badge/skills/nickcrew/claude-cortex/html-seo-review.svg" alt="Measured on agentmods" 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 | $0.00111 | $0.01115 |
| Opus 5 | $0.00056 | $0.00558 |
| Sonnet 5 | $0.00022 | $0.00223 |
| Haiku 4.5 | $0.00011 | $0.00112 |
Grade A, and why
html-seo-review scanned grade A with 1 finding 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
- An "Out-of-scope items noted" section listing anything the user should follow up with external tools (Lighthouse for real CWV, curl for canonical resolution, etc.). How it starts
The opening of the file, as written. The whole thing — 83 lines — stays where its author put it; the contents beside it link to each section on GitHub.
HTML SEO Review
Overview
Produce an actionable, severity-ranked findings list for one or more static HTML files. The skill bundles a stdlib-only HTML parser that extracts every SEO-relevant signal into a single JSON document, a comprehensive rubric, and a findings report template — together they let an audit run with predictable output every time.
When to use
Use when the input is one or more static .html files (or a directory of them) and the user wants on-page SEO findings they can act on. Triggers include "SEO review", "SEO audit", "check SEO on this HTML", "review meta tags on this page", "audit on-page SEO".
Do not use when:
- The artifact is source for a static-site generator (Jekyll/Hugo/Astro/Eleventy/Next.js). Those need source-aware review; defer to a future
ssg-seo-reviewskill. - The user wants live performance metrics (LCP, CLS, INP). HTML alone cannot produce these; recommend Lighthouse or PageSpeed Insights.
- The user wants backlink, domain authority, or other off-page analysis. That requires third-party tools (Ahrefs, SEMrush, etc.).
Workflow
1. Extract signals
Run the parser against the target. It accepts a single file or a directory (recursive *.html):
python3 scripts/extract_seo_signals.py <path> --pretty
Output is a JSON document with the following top-level keys: lang, title, meta, links, scripts, headings, images, links_audit, body_word_count. Each element carries a line number for citing in findings.
For a directory, the output is {"files": [<per-file object>]}.
The script uses only Python's standard library — no pip install required. If parsing fails on a specific file, the result for that file contains an error field and the audit continues for the rest.
2. Map signals to the rubric
Load references/seo-checklist.md. Walk each section in order and check the corresponding JSON path. The rubric explicitly lists the path to inspect for every check (e.g., images.missing_alt, meta.description.length, scripts.render_blocking_candidates).
What ships with it
3 files 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 · 83 lines · 111 tokens per session scan A 4cf900128d3f
html-seo-review is a skill published in the GitHub repository NickCrew/Claude-Cortex (38 stars, last pushed 2mo ago), licensed MIT. It adds 111 tokens to every session and 1,115 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
Other skills, from other repositories
create-stories
Break a single epic into implementable story files. Reads the epic, its GDD, governing ADRs, and control manifest. Each story embeds its GDD requirement TR-ID, ADR guidance, acceptance criteria, story type, and test evidence path. Run after /create-epics for each epic.
story-readiness
Validate that a story file is implementation-ready. Checks for embedded GDD requirements, ADR references, engine notes, clear acceptance criteria, and no open design questions. Produces READY / NEEDS WORK / BLOCKED verdict with specific gaps. Use when user says 'is this story ready', 'can I start on this story', 'is…
quick-design
Lightweight design spec for small changes — tuning adjustments, minor mechanics, balance tweaks. Skips full GDD authoring when a system GDD already exists or the change is too small to warrant one. Produces a Quick Design Spec that embeds directly into story files.
test-setup
Scaffold the test framework and CI/CD pipeline for the project's engine. Creates the tests/ directory structure, engine-specific test runner configuration, and GitHub Actions workflow. Run once during Technical Setup phase before the first sprint begins.
bug-triage
Read all open bugs in production/qa/bugs/, re-evaluate priority vs. severity, assign to sprints, surface systemic trends, and produce a triage report. Run at sprint start or when the bug count grows enough to need re-prioritization.
playtest-report
Generates a structured playtest report template or analyzes existing playtest notes into a structured format. Use this to standardize playtest feedback collection and analysis.