Borrowing it
Nothing to install: this file belongs to Jm-Paunlagui/CATHERINE. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/Jm-Paunlagui/CATHERINE/main/.claude/skills/feature-docs/SKILL.mdgit clone --depth 1 https://github.com/Jm-Paunlagui/CATHERINEWrote 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/jm-paunlagui/catherine/feature-docs)<a href="https://agentmods.dev/skills/jm-paunlagui/catherine/feature-docs"><img src="https://agentmods.dev/badge/skills/jm-paunlagui/catherine/feature-docs.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 | $0.00200 | $0.03361 |
| Opus 5 | $0.00100 | $0.01681 |
| Sonnet 5 | $0.00040 | $0.00672 |
| Haiku 4.5 | $0.00020 | $0.00336 |
Grade A, and why
feature-docs 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 6d 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 — 238 lines — stays where its author put it; the contents beside it link to each section on GitHub.
feature-docs
Produce a single, self-contained Markdown document that explains a feature the way a senior engineer would hand it off to a new teammate: what it does, how it flows (with diagrams), how the frontend and backend each implement it, how they talk to each other, the details that bite people, and the security posture. Optionally — only when asked — a code review.
The user typically gives you a short prompt and expects you to know the full shape of the deliverable. "I need documentation of the implementation and processes of the Authentication" means: produce the whole document below, grounded in the actual code, not a generic essay.
Step 1 — Resolve which folders to read
The document must describe real code. Before writing anything, figure out where the code lives.
Folder resolution order:
- Explicit names in the prompt. If the user names paired folders — e.g. "for the
auth-FEandauth-BE", "Name-FE and Name-BE", "thewebandapifolders" — use exactly those as the frontend and backend roots. The-FE/-BEsuffix convention maps to frontend/backend respectively. - Defaults. If no folders are named, look for a frontend root and a backend root using these common
names (case-insensitive): frontend →
Frontend,frontend,client,web,app,ui,fe; backend →Backend,backend,server,api,service,be. - Single tree / monorepo. If there's no clean FE/BE split (one app, or a monorepo with
packages/*), document it as a single codebase and skip the literal "Frontend vs Backend" split — instead use whatever real boundary exists (e.g.components/vsroutes/, orapps/webvsapps/api). - Nothing found / no code at all. If you can't locate the relevant code, say so plainly and ask the user for the path, OR — if they explicitly want a design/spec doc rather than docs of existing code — produce the document from their description and label the diagrams and sections clearly as proposed, not as documentation of shipped code. Never silently invent file paths, function names, or routes.
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.
- 6d ago First seen · 238 lines · 200 tokens per session scan A 58f60084c135
feature-docs is a skill published in the GitHub repository Jm-Paunlagui/CATHERINE (2 stars, last pushed 2d ago), licensed Apache-2.0. It adds 200 tokens to every session and 3,361 once invoked, about $0.0010 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 2026-08-31.
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