/skill-writer

Reference Architecture

Use this guide before adding bundled files or long sections to SKILL.md.

Router Rule

• SKILL.md is the router.
• References are flat lookup leaves under references/.
• SPEC.md is the maintenance contract.
• SOURCES.md stores provenance and decisions.

Lookup Test

Before creating a reference, finish this sentence:

• "I need to decide X, so read ...."
• "I need to do Y, so read ...."
• "I need to diagnose Z, so read ...."

If the sentence sounds like "I need context" or "I need patterns", the file is too vague.

Placement Table

Reference Types

Naming Rules

• Name files for the question or action they answer.
• Good: mode-selection.md, output-contracts.md, routing-workflows.md
• Bad: notes.md, context.md, patterns.md, research.md
• Prefer flat filenames over nested reference folders.
• When related references cover parallel variants of one lookup need, keep them as sibling files with a shared prefix plus an explicit differentiator.
• List every runtime reference directly in SKILL.md.

Split Rules

Create a new reference when:

• the content is only needed after a branch decision
• the content has one dominant type
• the section would make SKILL.md harder to scan
• the file is approaching 100 lines and contains multiple lookup needs
• the resulting file can be named as a direct child of references/ with a clear lookup reason

Keep content in SKILL.md when:

• every invocation needs it
• it is short
• moving it would force unnecessary file loads

Final Checks

1. Every runtime reference has a direct "open when..." reason in SKILL.md.
2. The filename tells the agent why to open it.
3. No required instruction is hidden only in an optional reference.
4. No reference has become a second SKILL.md.
5. No nested reference folder is introduced unless the content is non-runtime evidence or static assets.