Rule Creator

Create rule files in .claude/rules/. Rules are auto-discovered by Claude Code and loaded into agent context.

Step 0: Check for Existing Rule

Before creating, check if rule already exists:

test -f .claude/rules/<rule-name>.md && echo "EXISTS" || echo "NEW"

If EXISTS → use Read to inspect the current rule file, then Edit to apply changes directly. Run the post-creation integration steps (Step 4) after updating.

If NEW → continue with Step 0.5.

Step 0.5: Companion Check

Before proceeding with creation, run the ecosystem companion check:

1. Use companion-check.cjs from .claude/lib/creators/companion-check.cjs
2. Call checkCompanions("rule", "{rule-name}") to identify companion artifacts
3. Review the companion checklist — note which required/recommended companions are missing
4. Plan to create or verify missing companions after this artifact is complete
5. Include companion findings in post-creation integration notes

This step is informational (does not block creation) but ensures the full artifact ecosystem is considered.

When to Use

• Creating project-specific coding guidelines
• Documenting framework conventions
• Establishing team standards
• Defining workflow protocols

Rule File Format

Rules are simple markdown files:

# Rule Name

## Section 1

- Guideline 1
- Guideline 2

## Section 2

- Guideline 3
- Guideline 4

Example: testing.md

# Testing

## Test-Driven Development

- Use TDD for new features and bug fixes (Red-Green-Refactor cycle)
- Write failing test first, then minimal code to pass, then refactor
- Never write production code without a failing test first

## Test Organization

- Add unit tests for utilities and business logic
- Add integration tests for API boundaries
- Keep tests deterministic and isolated (no shared state)
- Place test files in `tests/` directory mirroring source structure

Creation Workflow

Step 1: Validate Inputs

// Validate rule name (lowercase, hyphens only)
const ruleName = args.name.toLowerCase().replace(/[^a-z0-9-]/g, '-');

// Validate content is not empty
if (!args.content || args.content.trim().length === 0) {
  throw new Error('Rule content cannot be empty');
}

Step 2: Create Rule File

const rulePath = `.claude/rules/${ruleName}.md`;

// Format content as markdown
const content = args.content.startsWith('#')
  ? args.content
  : `# ${ruleName.replace(/-/g, ' ').replace(/\b\w/g, l => l.toUpperCase())}\n\n${args.content}`;

await writeFile(rulePath, content);

Mandatory: Register in index

pnpm index-rules

Verify total_rules count increased. Rule is invisible to agents until indexed.

Step 3: Verify Auto-Discovery

Rules in .claude/rules/ are automatically loaded by Claude Code. No manual registration needed.

// Verify file was created
const fileExists = await exists(rulePath);
if (!fileExists) {
  throw new Error('Rule file creation failed');
}

Step 4: Run Post-Creation Integration

const {
  runIntegrationChecklist,
  queueCrossCreatorReview,
} = require('.claude/lib/creators/creator-commons.cjs');

await runIntegrationChecklist('rule', rulePath);
await queueCrossCreatorReview('rule', rulePath, {
  artifactName: ruleName,
  createdBy: 'rule-creator',
});

Post-Creation Integration

After rule creation, run integration checklist:

const {
  runIntegrationChecklist,
  queueCrossCreatorReview,
} = require('.claude/lib/creators/creator-commons.cjs');

// 1. Run integration checklist
const result = await runIntegrationChecklist('rule', '.claude/rules/<rule-name>.md');

// 2. Queue cross-creator review
await queueCrossCreatorReview('rule', '.claude/rules/<rule-name>.md', {
  artifactName: '<rule-name>',
  createdBy: 'rule-creator',
});

// 3. Review impact report
// Check result.mustHave for failures - address before marking complete

Integration verification:

• Rule file created in .claude/rules/
• Rule is auto-discovered by Claude Code
• Rule content is clear and actionable
• No conflicts with existing rules

Usage Examples

Create Code Standards Rule

Skill({
  skill: 'rule-creator',
  args: `--name code-standards --content "# Code Standards

## Organization
- Prefer small, cohesive files over large ones
- Keep interfaces narrow; separate concerns by feature

## Style
- Favor immutability; avoid in-place mutation
- Validate inputs and handle errors explicitly"`,
});

Create Git Workflow Rule

Skill({
  skill: 'rule-creator',
  args: `--name git-workflow --content "# Git Workflow

## Commit Guidelines
- Keep changes scoped and reviewable
- Use conventional commits: feat:, fix:, refactor:, docs:, chore:

## Branch Workflow
- Create feature branches from main
- Never force-push to main/master"`,
});

Related Skills

• skill-creator - Create detailed workflows (for complex guidance needing a full SKILL.md)
• hook-creator - Create enforcement hooks that accompany governance rules

Iron Laws

1. Every artifact MUST have a companion schema — Rules without a schema have no contract for structured validation. Create a JSON schema in .claude/schemas/ if the rule produces structured output or has configurable parameters.
2. Every artifact MUST be wired to at least one agent — A rule not referenced by any agent or skill is orphaned. Verify the rule is relevant to at least one agent's context (rules in .claude/rules/ are auto-loaded, but domain-specific rules should be referenced in agent prompts).
3. Every artifact MUST be indexed in its catalog — Rules not tracked in the catalog are hard to discover and audit. Add an entry or verify presence in the appropriate catalog.
4. Every artifact MUST pass integration validation — Run node .claude/tools/cli/validate-integration.cjs <rule-path> before marking creation complete. A rule that fails validation may have broken references or conflicts.
5. Every artifact MUST record a memory entry — Write the rule creation pattern, decisions, and any issues to .claude/context/memory/ (learnings.md, decisions.md, issues.md). Without memory, the creation is invisible to future sessions.

Memory Protocol (MANDATORY)

Before starting: Read .claude/context/memory/learnings.md

After completing:

• New rule pattern → .claude/context/memory/learnings.md
• Rule creation issue → .claude/context/memory/issues.md
• Guideline decision → .claude/context/memory/decisions.md

ASSUME INTERRUPTION: If it's not in memory, it didn't happen.

Cross-Reference: Creator Ecosystem

This skill is part of the Creator Ecosystem. When research uncovers gaps, trigger the appropriate companion creator:

Ecosystem Alignment Contract (MANDATORY)

This creator skill is part of a coordinated creator ecosystem. Any artifact created here must align with and validate against related creators:

• agent-creator for ownership and execution paths
• skill-creator for capability packaging and assignment
• tool-creator for executable automation surfaces
• hook-creator for enforcement and guardrails
• rule-creator and semgrep-rule-creator for policy and static checks
• template-creator for standardized scaffolds
• workflow-creator for orchestration and phase gating
• command-creator for user/operator command UX

Cross-Creator Handshake (Required)

Before completion, verify all relevant handshakes:

1. Artifact route exists in .claude/CLAUDE.md and related routing docs.
2. Discovery/registry entries are updated (catalog/index/registry as applicable).
3. Companion artifacts are created or explicitly waived with reason.
4. validate-integration.cjs passes for the created artifact.
5. Skill index is regenerated when skill metadata changes.

Research Gate (Exa + arXiv — BOTH MANDATORY)

For new patterns, templates, or workflows, research is mandatory:

1. Use Exa for implementation and ecosystem patterns:
   • mcp__Exa__web_search_exa({ query: '<topic> 2025 best practices' })
   • mcp__Exa__get_code_context_exa({ query: '<topic> implementation examples' })
2. Search arXiv for academic research (mandatory for AI/ML, agents, evaluation, orchestration, memory/RAG, security):
   • Via Exa: mcp__Exa__web_search_exa({ query: 'site:arxiv.org <topic> 2024 2025' })
   • Direct API: WebFetch({ url: 'https://arxiv.org/search/?query=<topic>&searchtype=all&start=0' })
3. Record decisions, constraints, and non-goals in artifact references/docs.
4. Keep updates minimal and avoid overengineering.

arXiv is mandatory (not fallback) when topic involves: AI agents, LLM evaluation, orchestration, memory/RAG, security, static analysis, or any emerging methodology.

Regression-Safe Delivery

• Follow strict RED -> GREEN -> REFACTOR for behavior changes.
• Run targeted tests for changed modules.
• Run lint/format on changed files.
• Keep commits scoped by concern (logic/docs/generated artifacts).