web-presence-audit

web-presence-audit is a skill for Claude Code from Kin9Zeus/senior-engineer-skills. It costs 204 tokens per session (3,864 once invoked), scanned A, original, MIT.

A review and implementation guide for the public-facing parts of a website. It covers technical SEO, the practices that help search engines find and understand pages, plus metadata, structured data, accessibility, and visitor trust.

In plain words
What is it for?
Use it to check robots.txt, sitemaps, canonical URLs, 404 pages, page titles, descriptions, social previews, image text alternatives, schema such as LocalBusiness or FAQ, internal links, and conversion details.
Why use it?
It finds quiet sources of lost search traffic, confusing search previews, broken indexing, inaccessible pages, and missing signs that a business is trustworthy.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the senior-engineer-skills plugin — 15 skills, 7 commands, 4 agents shipped together

Good fit Use it to check robots.txt, sitemaps, canonical URLs, 404 pages, page titles, descriptions, social previews, image text alternatives, schema such as LocalBusiness or FAQ, internal links, and conversion details.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/kin9zeus/senior-engineer-skills/web-presence-audit
Install

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.

Any agent
npx skills add Kin9Zeus/senior-engineer-skills --skill web-presence-audit
Clone the repo
git clone --depth 1 https://github.com/Kin9Zeus/senior-engineer-skills

Made for: Claude Code.

Or install senior-engineer-skills, the plugin that ships this one along with the rest of its 15 skills, 7 commands, 4 agents.

Wrote 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.

agentmods badge for web-presence-audit

README.md
[![agentmods](https://agentmods.dev/badge/skills/kin9zeus/senior-engineer-skills/web-presence-audit/github.svg)](https://agentmods.dev/skills/kin9zeus/senior-engineer-skills/web-presence-audit)
Your own site
<a href="https://agentmods.dev/skills/kin9zeus/senior-engineer-skills/web-presence-audit"><img src="https://agentmods.dev/badge/skills/kin9zeus/senior-engineer-skills/web-presence-audit/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.

agentmods 80×15 button for web-presence-audit

Your own site · 80×15
<a href="https://agentmods.dev/skills/kin9zeus/senior-engineer-skills/web-presence-audit"><img src="https://agentmods.dev/badge/skills/kin9zeus/senior-engineer-skills/web-presence-audit.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 204 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,864 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00204 $0.03864
Opus 5 $0.00102 $0.01932
Sonnet 5 $0.00041 $0.00773
Haiku 4.5 $0.00020 $0.00386

Measured 12d ago against content hash 9246e9a70615, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

web-presence-audit 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 12d ago.

The scan reads SKILL.md. This mod also ships 2 executable files (scripts/web-check.ps1, scripts/web-check.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

`curl -o /dev/null -w '%{http_code}' https://site.com/nonexistent-xyz`.
skills/web-presence-audit/SKILL.md · 353 lines

How it starts

The opening of the file, as written. The whole thing — 353 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Web Presence Audit

The public surface is where the product meets people who do not yet trust it. Every gap here costs traffic, conversion or credibility — and unlike most engineering debt, the cost is continuous and silent.

This skill covers four layers. Run them in order; each depends on the one above.

1. CRAWLABLE   Can a machine find, fetch and index this at all?
2. LEGIBLE     Does each page declare what it is, uniquely and correctly?
3. STRUCTURED  Can a machine understand the entities and answer questions with it?
4. TRUSTED     Would a stranger believe this is a real business and act?

Verify against the live rendered page, not the source. Server-side headers, proxies, CDNs and client-side rendering all change what a crawler actually sees. Run scripts/web-check.sh <url> for the automated first pass.


Layer 1 — Crawlable

Check Requirement Severity if missing
robots.txt Exists at the root, does not accidentally block the site, references the sitemap P1
sitemap.xml Generated (never hand-maintained), only canonical indexable URLs, submitted to Search Console P2
Custom 404 Returns a real 404 status, offers navigation and search, does not dead-end P2
Custom 500 Branded, leaks no stack trace P2
Canonical URL One per page, self-referencing by default P2
HTTPS Enforced, HTTP redirected once, no mixed content P1
One hostname www and apex resolve to one canonical host, 301 not 302 P2
Trailing slash Consistent; the other form redirects P3
No index bloat Filters, sorts, pagination and internal search not indexable P2
Render check Content present without JavaScript, or server-rendered P1 for a content site
No orphan pages Every important page reachable by internal links P2

The two failures that silently destroy traffic:

A soft 404 — a missing page returning 200 with "not found" text. Crawlers index it, and every mistyped URL becomes a thin duplicate page. Test with curl -o /dev/null -w '%{http_code}' https://site.com/nonexistent-xyz.

Read the full file on GitHub · 353 lines

Changes

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.

  1. 12d ago First seen · 353 lines · 204 tokens per session scan A 9246e9a70615

Subscribe to this mod's changes

web-presence-audit is a skill published in the GitHub repository Kin9Zeus/senior-engineer-skills (3 stars, last pushed 18d ago), licensed MIT. It adds 204 tokens to every session and 3,864 once invoked, about $0.0010 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 2026-08-31.

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