Writing Conformant Specifications

Guides creation and iteration of RFC 2119-conformant specifications. Supports active writing: structuring documents, choosing keywords as requirements are drafted, separating normative from informative content, and progressively refining through iteration.

When to Use

This skill should be used when:

• Creating new specification documents from scratch
• Iterating on specification drafts to improve conformance
• Drafting requirements and choosing appropriate keywords
• Structuring specification sections
• Converting plain language to RFC 2119 format
• Separating normative requirements from informative guidance
• Progressively refining specifications section-by-section

Instructions

1. Load Reference Guide

Read references/rfc-2119-guide.md for keyword definitions, decision tree, structure patterns, normative/informative separation patterns, validation checklist, and examples.

2. Support Creation and Iteration

Primary use case: Help create conformant specifications through active writing and iteration.

Creating: Guide structure, suggest patterns (Conformance Levels, Content Focus, Typical Content + Requirements), help draft with keywords, establish normative/informative separation, reference plan-spec.md and tasklist-spec.md examples.

Iterating: Convert plain language to RFC 2119 requirements, refine keyword choices, add informative labels, restructure for clarity, validate and suggest refinements.

Quick assistance: Answer keyword questions during writing, provide labeling guidance, clarify normative vs informative, suggest patterns, reference decision tree.

Validation: Check conformance when ready, identify violations with line numbers, count keywords, suggest improvements.

3. Iterative Writing Workflow

Support this cycle: Draft section → Keyword requirements → Label informative content → Validate → Refine → Next section

Provide guidance at any step. Support jumping between steps as writing progresses naturally.

4. Apply Decision Tree

Is requirement critical for correctness/safety/core functionality?
├─ Yes → MUST / MUST NOT
└─ No → Strongly recommended for quality?
    ├─ Yes → SHOULD / SHOULD NOT
    └─ No → Completely optional?
        └─ Yes → MAY / OPTIONAL

Provide keyword with example in context, rationale, reference to similar usage, and consideration of what happens if not met.

5. Reference Common Patterns

From guide: Conformance Levels (Level 1/2/3), Content Focus (MUST/MUST NOT), Typical Content + Requirements (separation), Common Mistakes → Best Practices (educational). See references/rfc-2119-guide.md for detailed examples and code.

6. Common Workflows

Write requirements section: Suggest structure pattern, help draft with keywords, separate examples from requirements, validate.

Choose keywords while drafting: Read draft, apply decision tree, suggest keywords with rationale, show transformation, explain implications.

Convert plain language to RFC 2119: Identify requirements vs explanations vs examples, apply keywords, add informative labels, structure using patterns, validate.

Structure specification: Understand scope, suggest conformance level approach, recommend organization, reference plan-spec.md or tasklist-spec.md, provide template.

Make draft conformant: Identify plain imperatives → RFC keywords, unlabeled examples → informative labels, subjective terms → measurable criteria, validate, refine.

Refine keyword strength: Analyze context, apply decision tree (what if not met?), consider conformance implications, recommend with rationale.

7. Provide Actionable Guidance

Structuring: Section organization from patterns, templates with RFC 2119 structure, references to similar specs.

Keywords: Specific keyword with context example, WHY it matches criticality, before/after, what happens if violated.

Separation: Identify normative (requirements) vs informative (guidance/examples), exact labels ("(Informative)", "Best Practice:", "Tip:"), placement, restructure if needed.

Iteration: Read draft, identify improvements, prioritize (critical first), refine section-by-section, validate and iterate.

Validation: Run checklist, report keyword counts, list issues with fixes, assess conformance, suggest next improvements.

Resource Structure

Self-contained with bundled resources:

• SKILL.md - Core instructions for creation and iteration
• references/rfc-2119-guide.md - Complete reference (12K): definitions, decision tree, patterns, validation checklist, examples, external resources

Load reference guide for detailed patterns and validation criteria.

Support active creation and iterative refinement. Write conformant specifications correctly from the start, then progressively improve.