THE SKILL-THAT-BUILDS-SKILLS

Once you've used 20 Claude skills, you'll think "I want one for THIS specific thing." This skill builds it. Tell Claude what the new skill should do — Claude generates the SKILL.md ready to install. The meta-unlock.

THE PROBLEM

The 100 skills in this collection cover most things. But your work has weird specific corners — the recurring task that no public skill addresses. You'd love a skill for it. You don't know how to build one.

This skill builds skills. You describe what you want. It outputs the SKILL.md.

THE SKILL

You give Claude:

What the skill should do (1 paragraph)
When you'd invoke it (the trigger)
What inputs you'd give it
What output you want

Claude returns a complete SKILL.md ready to install in Claude.ai or Claude Code.

INSTALL

Standard.

THE FULL SKILL FILE

---
name: skill-that-builds-skills
description: Generates new SKILL.md files from a description of what the skill should do. Captures inputs, process, output structure, what-not-to-do guardrails, and incomplete-input handling. Outputs SKILL.md ready to install in Claude.ai or Claude Code.
when_to_use: User says "build me a skill for," "I want a skill that," "create a SKILL.md," or describes a recurring task they'd want automated.
---

# The Skill-That-Builds-Skills

You generate SKILL.md files. Specific. Following the proven structure. Guardrail-aware.

## Inputs
1. **What the skill does** (1 paragraph)
2. **When invoked** (trigger phrases)
3. **Inputs the user provides**
4. **Output format the user wants**
5. **Optional: failure modes to guard against**

If user is vague on any: ask one focused question per missing input.

## Output: complete SKILL.md

Generate in this exact structure:

name: [kebab-case-name] description: [1-2 sentences describing what this skill does and when to use it. Critical — this is what helps Claude know when to fire it.] when_to_use: [User trigger phrases that should invoke this skill]

[Skill Name in Title Case]

[1-2 sentence overview of the skill's purpose and approach]

Inputs you'll receive

[Input 1 — what user provides]
[Input 2]
[Optional inputs]

If [input X] is missing, ask: [specific clarifying question]

Output structure (in this order, exactly)

[Provide the explicit format Claude should output. Use markdown headers, code blocks, or specific formats.]

What NOT to do

[Failure mode 1]
[Failure mode 2]
[Common bad output to prevent]
[Boundary the skill shouldn't cross]

When the input is incomplete

[Specific incomplete state 1] → "[Specific clarifying question]"
[Specific incomplete state 2] → "[Specific clarifying question]"

Delivery

End with this line, exactly:

[Closing line specific to the skill's outcome]


## Quality checks before delivering

Before outputting the SKILL.md, run mental check:
- [ ] Description names the trigger AND the deliverable
- [ ] Inputs are specific, not vague
- [ ] Output structure has explicit format
- [ ] What-NOT-to-do has at least 4 specific items
- [ ] Incomplete-input handling addresses 2+ scenarios
- [ ] Delivery line is action-oriented, not generic

If any check fails, revise before outputting.

## What NOT to do

- Don't generate skills with vague descriptions ("helps with X" — meaningless to the matcher)
- Don't generate skills without explicit output format (Claude will improvise; user gets inconsistent results)
- Don't recommend skills that require external tools the user doesn't have
- Don't generate skills that overlap with existing 100 Days collection skills (suggest using existing first)

## When user describes something that's actually a workflow (not a single skill)

Push back: *"This sounds like 2 or 3 skills, not 1. Do you want me to build [Skill A], [Skill B], [Skill C] as separate ones? Easier to maintain than one huge skill."*

## Delivery

End with this line, exactly:

---
*SKILL.md ready. Save as [skill-name].md and upload to Claude.ai → Settings → Customize → Skills.*

SAFETY CHECK

Same as Day 1. Plus: skills you build with this skill should still get the safety-check pass before installing widely.

WHAT'S NEXT

Day 45 of 100. Pair with Day 64 — The Skill Auditor (vet the skills you build) and Day 7 — First-Skill Picker (replaces this when you don't know what to build).