LerianStudio Writing Skills
When to use
- Creating a new skill
- Editing an existing skill
- Skill needs to resist rationalization under pressure
Skip when
- Writing pure reference skill (API docs) → no rules to test
- Skill has no compliance costs → no rationalization risk
Related
Complementary: ring:testing-skills-with-subagents
Writing skills IS TDD applied to process documentation.
Same Iron Law: No skill without failing test first.
Same cycle: RED (baseline) → GREEN (write skill) → REFACTOR (close loopholes).
REQUIRED BACKGROUND: Understand ring:test-driven-development before using this skill.
What is a Skill?
A reusable reference guide for proven techniques, patterns, or tools. Not a narrative about how you solved something once.
Create when: technique wasn't obvious, you'd reference it again, applies broadly.
Skip when: one-off solution, project-specific convention (put in CLAUDE.md).
Skill Types
| Type | Examples |
|---|---|
| Technique (steps to follow) | condition-based-waiting, root-cause-tracing |
| Pattern (way of thinking) | flatten-with-flags, test-invariants |
| Reference (docs/API) | API reference, command syntax |
SKILL.md Structure
---
name: ring:skill-name-with-hyphens
description: Use when [triggers/symptoms] — [what it does, third person]
---
# Skill Name
## Overview (1-2 sentences)
## When to Use (symptoms + skip conditions)
## Core Pattern (before/after examples)
## Quick Reference (table for scanning)
## Implementation (inline or linked)
## Common Mistakes
Frontmatter rules: Only name and description. Max 1024 chars total. name: letters, numbers, hyphens only. description: third-person, starts "Use when...", <500 chars if possible.
Agent Search Optimization (ASO)
Agents read description to decide which skills to load. Make it answer: "Should I read this skill right now?"
- Use concrete triggers and symptoms (problem-focused, not language-specific)
- Use keywords agents would search: error messages, symptoms, tool names
- Active voice, verb-first names:
creating-skillsnotskill-creation - Reference skills by name only:
ring:test-driven-development, no@links (force-loads context)
Token Efficiency
| Skill Type | Target |
|---|---|
| Bootstrap/getting-started | <150 words (loads in every session) |
| Simple technique | <500 words |
| Discipline-enforcing | <2,000 words (need rationalization tables) |
| Process/workflow | <4,000 words (multi-phase workflows) |
RED-GREEN-REFACTOR for Skills
| Phase | Action |
|---|---|
| RED | Run pressure scenario WITHOUT skill → document agent choices/rationalizations verbatim |
| GREEN | Write skill addressing specific failures → verify agent now complies |
| REFACTOR | Find new rationalizations → add counters → re-test until bulletproof |
REQUIRED SUB-SKILL: Use ring:testing-skills-with-subagents for pressure scenarios and hole-plugging.
The Iron Law
NO SKILL WITHOUT A FAILING TEST FIRST
Applies to new skills AND edits. Delete untested skills and start over. No exceptions.
Bulletproofing Against Rationalization
For discipline-enforcing skills:
- Forbid specific workarounds explicitly — don't just state the rule, list prohibited alternatives
- Address "spirit vs letter" early:
"Violating the letter is violating the spirit." - Build rationalization table from baseline testing — capture every excuse agents make
- Create Red Flags list — make self-checking easy
## Red Flags — STOP
- [symptom 1]
- [symptom 2]
All of these mean: [required action].
Skill Creation Checklist
| Phase | Requirements |
|---|---|
| RED | 3+ pressure scenarios, run WITHOUT skill, document rationalizations verbatim |
| GREEN | Valid frontmatter, description starts "Use when...", addresses baseline failures, one excellent example, verify compliance |
| REFACTOR | Rationalization table, Red Flags list, re-test against new loopholes |
| Quality | Flowchart only if non-obvious, quick ref table, no narrative |
| Deploy | Commit and push |
STOP after each skill — do NOT batch-create without testing each.
File Organization
| Type | Structure |
|---|---|
| Self-contained | skill/SKILL.md only |
| With tool | SKILL.md + reusable script |
| Heavy reference | SKILL.md + *.md refs + scripts/ |