authoring-adept-skills

authoring-adept-skills is a skill for Claude Code from itaywol/adeptability. It costs 45 tokens per session (914 once invoked), scanned A, original, MIT.

A guide for creating portable skills for AI coding agents. It explains how to write a SKILL.md file so one skill can be used by several coding-agent tools.

In plain words
What is it for?
Use it when creating or editing a skill, choosing when it should activate, checking its format, or running the adept skill command.
Why use it?
It helps avoid malformed skills, unclear activation rules, and limits that can prevent a skill from loading or working across tools.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: mentions Claude Code; mentions Codex.

Good fit Use it when creating or editing a skill, choosing when it should activate, checking its format, or running the adept skill command.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/itaywol/adeptability/authoring-adept-skills
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 itaywol/adeptability --skill authoring-adept-skills
Clone the repo
git clone --depth 1 https://github.com/itaywol/adeptability

Made for: Claude Code.

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 authoring-adept-skills

README.md
[![agentmods](https://agentmods.dev/badge/skills/itaywol/adeptability/authoring-adept-skills/github.svg)](https://agentmods.dev/skills/itaywol/adeptability/authoring-adept-skills)
Your own site
<a href="https://agentmods.dev/skills/itaywol/adeptability/authoring-adept-skills"><img src="https://agentmods.dev/badge/skills/itaywol/adeptability/authoring-adept-skills/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 authoring-adept-skills

Your own site · 80×15
<a href="https://agentmods.dev/skills/itaywol/adeptability/authoring-adept-skills"><img src="https://agentmods.dev/badge/skills/itaywol/adeptability/authoring-adept-skills.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 45 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 914 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. 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 $0.00045 $0.00914
Opus 5 $0.00023 $0.00457
Sonnet 5 $0.00009 $0.00183
Haiku 4.5 $0.00005 $0.00091

Measured 10d ago against content hash cb7300188f38, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

authoring-adept-skills 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 10d 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.

.adeptability/skills/authoring-adept-skills/SKILL.md · 80 lines

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.

Authoring a good adept skill

A skill is a directory <root>/skills/<id>/ with one SKILL.md (YAML frontmatter + markdown body) and optional sidecars. adept renders it into every enabled harness, so write it once, well, and harness-neutral.

Canonical SKILL.md format

---
id: pr-review                 # ^[a-z0-9](?:[a-z0-9-]{0,48}[a-z0-9])?$ — matches the directory name
description: Use before opening a PR. Tests, security, performance.   # <= 280 chars
activation: agent             # always | globs | agent | manual
globs: []                     # REQUIRED when activation: globs (e.g. ["**/*.go"])
allowed-tools: [Read, Grep]   # carried into Claude Code
targets: []                   # empty = all enabled harnesses
tags: [review, quality]
---
# PR Review Checklist
- [ ] Tests added or updated
- [ ] No secrets in the diff

Validated against pkg/adeptschema/skill.schema.json on every load — adept sync fails loudly on a malformed skill, so let it catch your mistakes.

Pick activation deliberately — this is the whole game

activation Fires when Use for
agent The model decides from the description Most skills. Procedures, checklists, how-tos.
globs A matching file is in context Language/path-specific rules (**/*.go, **/*.tsx).
always Every request Rare. Project-wide invariants only — costs budget on every turn.
manual Only when explicitly invoked Heavy or destructive procedures you don't want auto-firing.

The description is the trigger — write it like one

For activation: agent, the description is the only thing the model sees when deciding whether to load the skill. Make it earn the load:

  • Lead with when to apply, not what it is: "Use before opening a PR…" beats "A PR helper."
  • Name concrete nouns the user will say (file types, commands, tools, error strings).
  • One line, ≤ 280 chars. If you can't say when it applies in one line, the skill is too broad — split it.

Read the full file on GitHub · 80 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. 10d ago First seen · 80 lines · 45 tokens per session scan A cb7300188f38

Subscribe to this mod's changes

authoring-adept-skills is a skill published in the GitHub repository itaywol/adeptability (9 stars, last pushed 1mo ago), licensed MIT. It adds 45 tokens to every session and 914 once invoked, about $0.0002 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.