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name: spec-decomposer description: Decompose large unified specifications into agent skills with progressive disclosure. Use when converting documentation, frameworks, or knowledge bases exceeding 50KB into properly structured skills that an AI agent can navigate efficiently.

Specification Decomposer

Transform large unified specifications into agent skills with multi-level progressive disclosure.

When to Use

• Source specification exceeds 50KB (too large for single context load)
• Content has natural semantic groupings (domains, topics, categories)
• Granular access needed (load only relevant parts per query)
• Source has atomic units (patterns, sections, articles) that can stand alone

Core Workflow

1. Analyze source spec structure and size
2. Identify semantic domains (not structural divisions)
3. Map atomic units to domains
4. Design navigation architecture:
   • SKILL.md as AI decision hub
   • Domain indexes with manual navigation + auto-generated tables
   • Pattern preservation strategy for updates
5. Generate 4-level hierarchy:
   • Level 1: SKILL.md frontmatter (always loaded)
   • Level 2: SKILL.md body (on skill trigger)
   • Level 3: Domain index files (on domain access)
   • Level 4: Individual unit files (on specific need)
6. Implement generation script with navigation preservation
7. Validate file sizes (<50KB each)

Key Principles

Semantic over Structural

Group by meaning/use-case, NOT by source document structure.

Bad: Part A, Part B, Part C (mirrors source structure) Good: foundations, workflows, trust-assessment (mirrors usage)

Individual over Clustered

Keep atomic units separate with TOC navigation.

Bad: Cluster related items into single files Good: Individual files + domain index with "Load when..." guidance

Why: Clustering forces loading unnecessary context. Individual files + TOC = load exactly what's needed.

Levels Encoded by Convention

domain/
├── index.md          # Level 3 (always named index.md)
├── unit_1.md         # Level 4
└── unit_2.md         # Level 4

No separate level folders - the level is implicit in the file role.

File Size Limits

Level	Max Size	Content
L2 SKILL.md body	50KB / ~500 lines	Core workflow + domain navigation
L3 domain/index.md	20KB / ~200 lines	Domain overview + unit TOC
L4 individual files	50KB	Single atomic unit

If a unit exceeds 50KB, split into sub-units with their own index.

Optional Directories

According to the Agent Skills specification, three optional directories can enhance your skill:

references/prompts/

For complex skills, add operational prompts in references/prompts/:

File	Purpose
workflow.md	Step-by-step process for using the skill
principles.md	Quick reference for key concepts
keywords.md	Navigation hints, search terms

Prompts help the agent know HOW to use the decomposed content effectively. See references/operational-prompts.md for details.

assets/

Store static resources that support the skill:

• Templates (document templates, configuration templates)
• Images (diagrams, examples)
• Data files (lookup tables, schemas)

scripts/

Automation scripts for maintaining the skill structure (generation, validation, etc.)

Frontmatter Extensions

The official Agent Skills specification defines a minimal set of required fields (name, description) and optional fields (license, compatibility, metadata, allowed-tools).

Specific clients (e.g., Cursor) may extend frontmatter with additional fields:

• priority: high - skill loading priority
• auto_load: true - automatic activation

Such extensions maintain backward compatibility with the base specification.

References

• 4-level architecture details: See references/4-level-architecture.md
• Navigation architecture: See references/navigation-architecture.md - SKILL.md and index.md structure patterns
• Domain identification: See references/domain-grouping.md
• Size enforcement: See references/size-constraints.md
• Operational prompts: See references/operational-prompts.md