Borrowing it
Nothing to install: this file belongs to Klerith/fernando-skills. 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/Klerith/fernando-skills/main/CLAUDE.mdgit clone --depth 1 https://github.com/Klerith/fernando-skillsWrote 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/instructions/klerith/fernando-skills/claude-md)<a href="https://agentmods.dev/instructions/klerith/fernando-skills/claude-md"><img src="https://agentmods.dev/badge/instructions/klerith/fernando-skills/claude-md/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/instructions/klerith/fernando-skills/claude-md"><img src="https://agentmods.dev/badge/instructions/klerith/fernando-skills/claude-md.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 | $0.01133 | $0.01133 |
| Opus 5.5 | $0.00453 | $0.00453 |
| Sonnet 5.5 | $0.00227 | $0.00227 |
| Haiku 4.5 | $0.00113 | $0.00113 |
Grade A, and why
fernando-skills CLAUDE.md 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 2mo 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 — 80 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Purpose
This repo is a workspace for authoring Claude Code slash-command skills, specifically for a spec-driven development workflow. Skills are written in English, and they instruct the agent to reply in whatever language the user's prompt used.
reference/ is a vendored copy of mattpocock/skills kept as a structural/style reference — do not edit it during normal work. Its own reference/CLAUDE.md governs that subtree.
Skill authoring conventions
Each skill lives under skills/<bucket>/<name>/ (e.g. skills/engineering/spec/) as a directory containing at minimum a SKILL.md. Buckets group skills by domain (engineering/, future: productivity/, misc/, etc.). The YAML frontmatter of SKILL.md must declare:
---
name: skill-name
description: One-line description (in Spanish)
disable-model-invocation: true
argument-hint: [hint]
---
Use allowed-tools in frontmatter to restrict what Bash commands a skill may run (see skills/engineering/spec-impl/SKILL.md for an example that limits to read-only git/fs).
Use !command``shell snippets insideSKILL.md to inject live repo state at skill-load time (e.g., current branch, available specs). Embed them at the top of the skill body before the instructions.
Companion files (e.g., template.md) sit next to SKILL.md and are referenced by relative path within the skill body.
The spec workflow
This repo encodes a two-skill pair:
/spec
Guides the user through 4 phases: read project context → clarify with questions (blocks of 3–5) → draft each spec section one at a time with user confirmation → save to specs/NN-slug.md.
On save, it also seeds specs/.spec-config.yml (default AutoCreateBranch: true) only if the file is missing — an existing config is never overwritten. This is how the AutoCreateBranch flag that /spec-impl reads gets created without the user knowing the file exists.
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.
- 2mo ago First seen · 80 lines · 1,133 tokens per session scan A d8382a4d19db
fernando-skills CLAUDE.md is an instructions file published in the GitHub repository Klerith/fernando-skills (347 stars, last pushed 21d ago), licensed MIT. It adds 1,133 tokens to every session, about $0.0045 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 2026-08-30.
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