build-skill - SKILL.md Agent Skill

name: build-skill description: Create or update a skill, agent, and reference file context: fork agent: build-skill

Build Skill

Create skills for editing tabs/*.json config files.

File Structure

.claude/
├── skills/{name}/
│   ├── SKILL.md           # Curated rules and formats
│   └── references/
│       └── {name}-reference.md  # Complete schema
└── agents/{name}.md       # Agent that uses the skill

Skill Template

---
name: {name}
description: Schema and rules for creating {plural}
context: fork
agent: {name}
---

# {Title}

Edit `tabs/{name}.json`.

## Required Fields

| Field | Requirement |
|-------|-------------|
| `field` | What to put here |

## Conditional Fields

| Field | When to Include |
|-------|-----------------|
| `field` | Only when X |

## Never Include

Omit these fields (auto-set or unused):
- `field1`, `field2`, `field3`

## {fieldName} Format

{Brief description of structure}

Format: "{template with [placeholders]}"

## Schema

\`\`\`typescript
interface {Type} {
  field: type
}
\`\`\`

## Reference

For detailed documentation, see [{name}-reference.md](references/{name}-reference.md).

Agent Template

---
name: {name}
description: |
  Use this agent when the user wants to add or edit {plural}.
model: haiku
permissionMode: bypassPermissions
skills:
  - {name}
---

You create and edit {plural} in `tabs/{name}.json`.

## Chaining

If `{cross-reference}` doesn't exist in `tabs/{other}.json`, spawn **{other}** agent in parallel.

Reference Template

# {Title} Reference

Complete documentation for `tabs/{name}.json`.

## Schema

\`\`\`typescript
interface {Type} {
  field: type                     // ✅ Description
  field?: type                    // ✅ Description with cross-ref to {other}.json
  field?: type                    // ⚠️ Calculated from X if undefined
  field: type                     // ❌ Always set to X
}
\`\`\`

### Legend

- ✅ **Predefine-able**: Can be set in config, preserved via spread
- ⚠️ **Calculated default**: Has fallback logic if not predefined
- ❌ **Always overwritten**: Set by initialization regardless of what exists in config

## {Related Schema if needed}

\`\`\`typescript
interface {RelatedType} {
  field: type                     // Description
}
\`\`\`

{Prose explanation of how it works, stacking rules, etc.}

## {Topic-Specific Section}

| Column | Column | Column |
|--------|--------|--------|
| value | value | value |

Formula: `{formula if applicable}`

## {Task Name}

Only runs when `condition: 'value'` and `otherCondition: true`

Reads `inputField` and generates: outputField1, outputField2, outputField3. Sets `flag` to false when complete.

## Cross-References

| Field | References |
|-------|------------|
| `field` | `tabs/{other}.json` |

Principles

Skill (SKILL.md) - Opinionated and curated

What this user wants
Formats and templates over examples
Required/Conditional/Never field tables
Brief, actionable guidance

Reference ({name}-reference.md) - Comprehensive and neutral

Everything the system supports
Full schema with all fields
Edge cases and defaults
Cross-references and limits

Agent ({name}.md) - Minimal orchestration

One-line description of when to use
Chaining logic for cross-references (only where invented values are common)
No duplication of skill content

Naming

Skill name = agent name = folder name
Use kebab-case for multi-word names
Match the tabs/*.json filename when possible