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 sergekostenchuk/ui-ux-agent-skill-system --skill existing-site-analyzergit clone --depth 1 https://github.com/sergekostenchuk/ui-ux-agent-skill-systemWrote 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/sergekostenchuk/ui-ux-agent-skill-system/existing-site-analyzer)<a href="https://agentmods.dev/skills/sergekostenchuk/ui-ux-agent-skill-system/existing-site-analyzer"><img src="https://agentmods.dev/badge/skills/sergekostenchuk/ui-ux-agent-skill-system/existing-site-analyzer/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/sergekostenchuk/ui-ux-agent-skill-system/existing-site-analyzer"><img src="https://agentmods.dev/badge/skills/sergekostenchuk/ui-ux-agent-skill-system/existing-site-analyzer.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 | $0.00065 | $0.00649 |
| Opus 5 | $0.00032 | $0.00324 |
| Sonnet 5 | $0.00013 | $0.00130 |
| Haiku 4.5 | $0.00006 | $0.00065 |
Grade A, and why
existing-site-analyzer 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 11d 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.
How it starts
The opening of the file, as written. The whole thing — 68 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Existing Site Analyzer
This skill creates the evidence base for existing-site work. It does not decide rebuild strategy by itself and does not mutate the live site.
Operating Modes
local-inventory: inspect local HTML, source files, assets, sitemap, robots, and reports.public-url-review: review public URLs or fetched HTML only after network/crawling approval.screenshot-review: analyze screenshots when URL or source is unavailable.asset-inventory: inventory images, videos, docs, icons, maps, and brand assets.handoff: produce evidence forrebuild-or-improve-advisorandmigration-planner.
Required Workflow
- Read references/existing-site-analysis-contract.md.
- Confirm source type and privacy:
- local files and user-provided public screenshots: allowed;
- public URL crawling/fetching: approval required if not already requested;
- authenticated/private pages, analytics, CRM, or CMS: explicit approval and data-handling note required.
- Use assets/existing-site-audit.template.md for the report.
- Record evidence status for every source:
Ran,Skipped,Planned, orManual. - Capture:
- page inventory;
- content and IA;
- SEO/LLM surface;
- UX and conversion issues;
- technical constraints;
- asset inventory;
- migration risks.
- Hand off to
rebuild-or-improve-advisor; involvemigration-plannerif URL structure, redirects, sitemap, robots, schema, or launch risk may change.
Safety Rules
- Do not crawl private/authenticated pages without explicit approval.
- Do not store private analytics exports, cookies, tokens, private URLs, or
.envvalues in reports. - Do not claim Lighthouse, browser, crawler, or DOM evidence unless it was actually run.
- Do not change production content, redirects, robots, sitemap, DNS, CMS, or deployment settings.
Handoff Shape
Mode:
Sources:
Evidence status:
Major findings:
SEO/LLM risks:
UX risks:
Technical constraints:
Asset inventory:
Migration risk:
Next owner:
What ships with it
4 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.
- 11d ago First seen · 68 lines · 65 tokens per session scan A f0e2112010f1
existing-site-analyzer is a skill published in the GitHub repository sergekostenchuk/ui-ux-agent-skill-system (23 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 65 tokens to every session and 649 once invoked, about $0.0003 per session on Opus 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 2026-08-30.
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