# Agent Tool Builder

> Tools are how AI agents interact with the world. A well-designed tool is the difference between an agent that works and one that hallucinates, fails silently, or costs 10x more tokens than necessary. This skill covers tool design from schema to error handling. JSON Schema best practices, description writing that actually helps the LLM, validation, and the emerging MCP standard that's becoming the lingua franca for AI tools. Key insight: Tool descriptions are more important than tool implementa

## Facts
- Page: https://tashan.sh/capability/skill-majiayu000-agent-tool-builder
- tashan id: skill:majiayu000/agent-tool-builder
- Source: https://github.com/majiayu000/claude-skill-registry
- Type: skill
- Category: devtools
- tashan score: 47.0 / 100
- Adoption: 14.0
- Upkeep: 82.0
- Freshness: 100.0
- Evidence coverage: 84% of the inputs this score can use
- Health: active
- Instruction depth: not yet graded
- License: MIT
- Official: no

## Install

```sh
cp -r agent-tool-builder ~/.claude/skills/
```

## Security audit
Not scanned. We audit npm-published capabilities; this one has no npm package we can resolve, or has not reached the queue. This is not a clean bill of health.

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Measured 2026-09-12 by tashan (https://tashan.sh) from public evidence. Scorer s5.