About tool-creator
A tool-creation skill for Claude project workflows. It guides creation of executable CommonJS or ESM tool files and their catalog and integration steps, including duplicate checks, companion reviews, and validation.
Key features
- 01Check for existing tools and detect duplicates
- 02Create CommonJS or ESM tools by category
- 03Update the tool catalog and run integration steps
- 04Review companion artifacts and record creation details
- 05Guide input validation and tool file structure
Use cases
- 01Create reusable command-line utilities
- 02Write code analysis or validation scripts
- 03Add workflow integration utilities
- 04Register and validate a new project tool
Install
Copy the command and run it in a terminal.
npx skills add https:/ / github.com/ oimiragieo/ agent-studio --skill tool-creatorAfter installing, type/tool-creatorin Claude Code to confirm it loaded.
Bundled files
References and scripts installed along with SKILL.md.
commands/tool-creator.mdhooks/post-execute.cjspre-execute.cjsreferences/research-requirements.mdrules/tool-creator.mdschemas/input.schema.jsonoutput.schema.jsonscripts/main.cjstemplates/implementation-template.mdDetails
From the project READMETool 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 totool-updaterskill 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.cjsfrom.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/creators/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/creators/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 toolshook-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.mdare invisible to discovery. Add an entry to.claude/context/artifacts/catalogs/tool-catalog.mdunder 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-creatorfor ownership and execution pathsskill-creatorfor capability packaging and assignmenttool-creatorfor executable automation surfaceshook-creatorfor enforcement and guardrailsrule-creatorandsemgrep-rule-creatorfor policy and static checkstemplate-creatorfor standardized scaffoldsworkflow-creatorfor orchestration and phase gatingcommand-creatorfor user/operator command UX
Cross-Creator Handshake (Required)
Before completion, verify all relevant handshakes:
- Artifact route exists in
.claude/CLAUDE.mdand related routing docs. - Discovery/registry entries are updated (catalog/index/registry as applicable).
- Companion artifacts are created or explicitly waived with reason.
validate-integration.cjspasses 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' })
- Via Exa:
- 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:
--helpresponse: Tool responds to--help(or-h) with a usage summary including required/optional arguments and at least one example invocationshell: falsefor child processes: Anychild_process.spawnorexecFilecall usesshell: falsewith array arguments (nevershell: trueper 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.mdwith 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.