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craft-skill

Create or improve agent skills from concrete behavior and evidence.

Skill by Astro-Han

IndexedMIT★ 12
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Install

Works with Claude Code, Claude apps, Codex, Cursor, Gemini CLI, GitHub Copilot, VS Code, OpenCode, Goose, Windsurf. Read the repository before you give any tool access to your data.

npx agentmarket install skill/astro-han-craft-skill

Asks which of your tools to add it to (Claude Code, Codex, Cursor, VS Code, Windsurf, Gemini CLI, Claude Desktop) and shows the change first. See https://agentmart.dev/cli.

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About

Create or improve agent skills from concrete behavior and evidence. Use when building or revising SKILL.md, or testing whether a skill earns its context. Do not use for ordinary documentation or one-off prompts.

Use cases: testing, agent-building

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Permissions

What this skill can do and what it asks for, from its SKILL.md. Checked Oct 25, 2026.

Tools
No tools found
Secrets
None asked for
Install scripts
None found
Runs as
Python package

Network hosts it talks to 1

  • codeload.github.com · found in install command

Files it touches

  • ~/.claude/skills/craft-skill

What's inside

Skill name
craft-skill
Description
Create or improve agent skills from concrete behavior and evidence. Use when building or revising SKILL.md, or testing whether a skill earns its context. Do not use for ordinary documentation or one-off prompts.
License
MIT
Instructions
47 lines in SKILL.md · view on GitHub

Before installing

  • Ships executable scripts

Files (5)

  • SKILL.md
  • openai.yaml · agents/
  • diagnosis.md · references/
  • evaluation.md · references/
  • eval.py · scripts/

SKILL.md (first lines)

# Craft Skill

A skill should be called for the right task, steer the agent to genuine completion, and make every token earn its place.

## Establish the job

Read the request, conversation, existing skill, repository conventions, and target platform's authoritative skill specification.

Define the useful behavior with realistic examples: what should call the skill, what should not, what the agent should do differently, and what observable evidence means it finished. Ask only about user-owned choices that materially change those answers. When revising a skill, preserve its name and inspect observed failures before editing.

## Call

- Follow the platform's metadata and invocation contract. Test triggering only when automatic invocation exists.
- Make the description identify the skill and its distinct trigger branches without leaking enough procedure to skip the body. One trigger per real branch; synonyms are not branches.
- Keep what every branch needs in `SKILL.md`. Put branch-specific knowledge behind a direct pointer that states when to load it.

Call is complete when every intended branch and close non-trigger has one clear owner, and the metadata passes the platform's validator when one exists.

## Steer

Use the lightest reliable medium:

- Put non-obvious judgment and sequence in instructions.
- Put knowledge the agent would rediscover in references.
- Put repeated, fragile, or deterministic operations in scripts.
- Put material copied into outputs in assets.

Match freedom to fragility. Use principles where several approaches work; tighten procedure or code only where variance causes failure.

Define completion from the requested outcome, not the procedure. Exhaustive means every decision-relevant item is accounted for, not every discoverable source or intermediate step is performed. End each step with a completion criterion the agent can check, with honest terminal states for missing evidence, unavailable input, and blocked actions. End with an overall postcondition that inspects the resulting artifact or state; completed steps are not final evidence.

## Earn

- Delete any sentence whose removal changes neither invocation nor execution.
- Keep each meaning in one authoritative place. Remove stale branches, duplication, and abstractions without present demand.
- Add code only when it makes repeated or error-prone work more reliable than instructions can; test it through its public seam.
- Evaluate only when the result can change a decision; otherwise stop.

When evidence could change the decision, read [references/evaluation.md](references/evaluation.md) before evaluating. When an existing skill misbehaves and the cause is unclear, read [references/diagnosis.md](references/diagnosis.md).

## Finish

Run the platform validator and relevant script tests. Confirm every resource has a condition-bearing pointer. Report the evidence and what remains unverified.

Stop when the concrete examples work and another deletion would damage Call, Steer, or the evidence needed to judge them.

From Astro-Han/skills, MIT.

More from Astro-Han/skills

Signals

Stars
12
Forks
3
Open issues
0
Last commit (this folder)
Jul 12, 2026 (3 months ago)

From GitHub (fetched Oct 24, 2026).

Details

License
MIT
First seen
Oct 24, 2026
Last checked
Oct 24, 2026

More from Astro-Han

Cite this page

craft-skill. Agent Mart. https://agentmart.dev/skills/astro-han-craft-skill (last updated 2026-10-24)