Tool Creator

Create executable tool files in .claude/tools/<category>/. Tools are organized into categories like cli, analysis, validation, integrations, etc.

Step 0: Check for Existing Tool

Before creating, check if tool already exists:

find .claude/tools/ -name "<tool-name>.*" -type f

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

If NEW → continue with Step 0.1.

Step 0.1: Smart Duplicate Detection (MANDATORY)

Before proceeding with creation, run the 3-layer duplicate check:

const { checkDuplicate } = require('.claude/lib/creation/duplicate-detector.cjs');
const result = checkDuplicate({
  artifactType: 'tool',
  name: proposedName,
  description: proposedDescription,
  keywords: proposedKeywords || [],
});

Handle results:

EXACT_MATCH: Stop creation. Route to tool-updater skill instead: Skill({ skill: 'tool-updater' })
REGISTRY_MATCH: Warn user — artifact is registered but file may be missing. Investigate before creating. Ask user to confirm.
SIMILAR_FOUND: Display candidates with scores. Ask user: "Similar artifact(s) exist. Continue with new creation or update existing?"
NO_MATCH: Proceed to next step.

Override: If user explicitly passes --force, skip this check entirely.

Step 0.5: Companion Check

Before proceeding with creation, run the ecosystem companion check:

Use companion-check.cjs from .claude/lib/creators/companion-check.cjs
Call checkCompanions("tool", "{tool-name}") to identify companion artifacts
Review the companion checklist — note which required/recommended companions are missing
Plan to create or verify missing companions after this artifact is complete
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 reusable command-line utilities
Building analysis or validation scripts
Implementing framework automation tools
Adding workflow integration utilities

Tool File Format

Tools are CommonJS or ESM modules with:

#!/usr/bin/env node
/**
 * Tool Name - Brief description
 *
 * Usage:
 *   node .claude/tools/<category>/<tool-name>.cjs [options]
 *
 * Options:
 *   --help     Show help
 *   --option   Description
 */

const main = async () => {
  // Tool implementation
};

if (require.main === module) {
  main().catch(console.error);
}

module.exports = { main };

Tool Categories

Category	Purpose	Examples
`cli`	Command-line utilities	validators, formatters
`analysis`	Code analysis tools	complexity, dependencies
`validation`	Validation scripts	schema, lint
`integrations`	External integration tools	API clients, webhooks
`maintenance`	Framework maintenance	cleanup, migration
`optimization`	Performance optimization	indexing, caching
`runtime`	Runtime utilities	config readers, loaders
`visualization`	Diagram and graph generation	mermaid, graphviz
`workflow`	Workflow automation	task runners, orchestrators
`gates`	Quality gates and checks	coverage, security
`context`	Context management	compression, handoff

Creation Workflow

Step 1: Validate Inputs

// Validate tool name (lowercase, hyphens, no spaces)
const toolName = args.name.toLowerCase().replace(/[^a-z0-9-]/g, '-');

// Validate category exists
const validCategories = [
  'cli',
  'analysis',
  'validation',
  'integrations',
  'maintenance',
  'optimization',
  'runtime',
  'visualization',
  'workflow',
  'gates',
  'context',
];

if (!validCategories.includes(args.category)) {
  throw new Error(`Invalid category. Must be one of: ${validCategories.join(', ')}`);
}

Step 2: Create Tool File

const toolPath = `.claude/tools/${args.category}/${toolName}.cjs`;

// Create tool directory if it doesn't exist
await mkdir(`.claude/tools/${args.category}`, { recursive: true });

// Generate tool content
const content = `#!/usr/bin/env node
/**
 * ${toolName.replace(/-/g, ' ').replace(/\b\w/g, l => l.toUpperCase())} - ${args.description || 'Tool description'}
 *
 * Usage:
 *   node .claude/tools/${args.category}/${toolName}.cjs [options]
 *
 * Options:
 *   --help     Show this help message
 */

${args.implementation}

if (require.main === module) {
  main().catch(console.error);
}

module.exports = { main };
`;

await writeFile(toolPath, content);

// Make executable (Unix-like systems)
if (process.platform !== 'win32') {
  await chmod(toolPath, '755');
}

Step 3: Update Tool Catalog

const catalogPath = '.claude/context/artifacts/catalogs/tool-catalog.md';

// Add entry to catalog under appropriate category
const newEntry = `| ${toolName} | ${args.description} | .claude/tools/${args.category}/${toolName}.cjs | active |`;

// Insert into catalog preserving category structure

Step 4: Run Post-Creation Integration

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

await runIntegrationChecklist('tool', toolPath);
await queueCrossCreatorReview('tool', toolPath, {
  artifactName: toolName,
  createdBy: 'tool-creator',
  category: args.category,
});

Post-Creation Integration

After tool creation, run integration checklist:

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

// 1. Run integration checklist
const result = await runIntegrationChecklist('tool', '.claude/tools/<category>/<tool-name>.cjs');

// 2. Queue cross-creator review
await queueCrossCreatorReview('tool', '.claude/tools/<category>/<tool-name>.cjs', {
  artifactName: '<tool-name>',
  createdBy: 'tool-creator',
  category: '<category>',
});

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

Integration verification:

Tool added to tool-catalog.md under correct category
Tool file is executable (Unix) or runnable (Windows)
Tool has help text and usage examples
Tool passes basic smoke test

Usage Examples

Create Validation Tool

Skill({
  skill: 'tool-creator',
  args: `--name schema-validator --category validation --implementation "
const validateSchema = async () => {
  console.log('Validating schema...');
};

const main = async () => {
  await validateSchema();
};
"`,
});

Create Analysis Tool

Skill({
  skill: 'tool-creator',
  args: `--name complexity-analyzer --category analysis --implementation "
const analyzeComplexity = async (filePath) => {
  console.log('Analyzing complexity for:', filePath);
};

const main = async () => {
  const [,, filePath] = process.argv;
  await analyzeComplexity(filePath);
};
"`,
});

Related Skills

skill-creator - Create skills that invoke tools
hook-creator - Create pre/post hooks that wrap tool execution

Iron Laws

Every artifact MUST have a companion schema — Tools without a schema have no contract; consumers cannot validate inputs/outputs. Create a JSON schema in .claude/schemas/ for the tool's CLI interface.
Every artifact MUST be wired to at least one agent — A tool not assigned to any agent is never invoked. Assign the tool to relevant agents via their tools: frontmatter array.
Every artifact MUST be indexed in its catalog — Tools not in tool-catalog.md are invisible to discovery. Add an entry to .claude/context/artifacts/catalogs/tool-catalog.md under the correct category.
Every artifact MUST pass integration validation — Run node .claude/tools/cli/validate-integration.cjs <tool-path> before marking creation complete. A tool that fails validation has broken references.
Every artifact MUST record a memory entry — Write the tool 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 tool pattern → .claude/context/memory/learnings.md
Tool creation issue → .claude/context/memory/issues.md
Category 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:

Gap Discovered	Required Artifact	Creator to Invoke	When
Domain knowledge needs a reusable skill	skill	`Skill({ skill: 'skill-creator' })`	Gap is a full skill domain
Existing skill has incomplete coverage	skill update	`Skill({ skill: 'skill-updater' })`	Close skill exists but incomplete
Capability needs a dedicated agent	agent	`Skill({ skill: 'agent-creator' })`	Agent to own the capability
Existing agent needs capability update	agent update	`Skill({ skill: 'agent-updater' })`	Close agent exists but incomplete
Domain needs code/project scaffolding	template	`Skill({ skill: 'template-creator' })`	Reusable code patterns needed
Behavior needs pre/post execution guards	hook	`Skill({ skill: 'hook-creator' })`	Enforcement behavior required
Process needs multi-phase orchestration	workflow	`Skill({ skill: 'workflow-creator' })`	Multi-step coordination needed
Artifact needs structured I/O validation	schema	`Skill({ skill: 'schema-creator' })`	JSON schema for artifact I/O
User interaction needs a slash command	command	`Skill({ skill: 'command-creator' })`	User-facing shortcut needed
Repeated logic needs a reusable CLI tool	tool	`Skill({ skill: 'tool-creator' })`	CLI utility needed
Narrow/single-artifact capability only	inline	Document within this artifact only	Too specific to generalize

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:

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

Research Gate (Exa + arXiv — BOTH MANDATORY)

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

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' })
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' })
Record decisions, constraints, and non-goals in artifact references/docs.
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).

Optional: Evaluation Quality Gate

Run the shared evaluation framework to verify tool quality:

node .claude/skills/skill-creator/scripts/eval-runner.cjs --skill tool-creator

Grader assertions for tool artifacts:

--help response: Tool responds to --help (or -h) with a usage summary including required/optional arguments and at least one example invocation
shell: false for child processes: Any child_process.spawn or execFile call uses shell: false with array arguments (never shell: true per SE-security rules)
Graceful missing input handling: Tool exits with a non-zero code and a human-readable error message when required arguments are absent; no unhandled exceptions or crash dumps
Catalog entry present: Tool is registered in .claude/context/artifacts/catalogs/tool-catalog.md with category, description, and wiring status
Timeout safety: Long-running operations have explicit timeouts; no infinite loops on missing input

See .claude/skills/skill-creator/EVAL_WORKFLOW.md for full evaluation protocol and grader/analyzer agent usage.