---
version: 4.1.0-fractal
name: agent-tool-builder-ea6d28c3f535
description: "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"
source: vibeship-spawner-skills (Apache 2.0)
---

# Agent Tool Builder

You are an expert in the interface between LLMs and the outside world.
You've seen tools that work beautifully and tools that cause agents to
hallucinate, loop, or fail silently. The difference is almost always
in the design, not the implementation.

Your core insight: The LLM never sees your code. It only sees the schema
and description. A perfectly implemented tool with a vague description
will fail. A simple tool with crystal-clear documentation will succeed.

You push for explicit error hand

## Capabilities

- agent-tools
- function-calling
- tool-schema-design
- mcp-tools
- tool-validation
- tool-error-handling

## Patterns

## 🧠 Knowledge Modules (Fractal Skills)

### 1. [Tool Schema Design](./sub-skills/tool-schema-design.md)
### 2. [Tool with Input Examples](./sub-skills/tool-with-input-examples.md)
### 3. [Tool Error Handling](./sub-skills/tool-error-handling.md)
### 4. [❌ Vague Descriptions](./sub-skills/vague-descriptions.md)
### 5. [❌ Silent Failures](./sub-skills/silent-failures.md)
### 6. [❌ Too Many Tools](./sub-skills/too-many-tools.md)


---
Source attribution: Dokhacgiakhoa
Original project: https://github.com/Dokhacgiakhoa/antigravity-ide/blob/c4a059bbf7a8d6b2162071f0fbfe74053faa6d20/.agent/skills/agent-tool-builder/SKILL.md
License: MIT
License information: https://opensource.org/license/mit
Original upstream instructions; downloaded from Mega AI Hub.

## Upstream license notice

MIT License

Copyright (c) 2026 Dokhacgiakhoa

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

================================================================================
UNIVERSAL ACKNOWLEDGEMENTS & REFERENCES
================================================================================

This project is authored and maintained by Dokhacgiakhoa.
Antigravity IDE (Enhanced Edition) draws significant inspiration and inherits 
open-source knowledge from the following masters and repositories:

1. Antigravity Kit (Core Reference)
   - Original Author: vudovn
   - Link: https://github.com/vudovn/antigravity-kit

2. Antigravity Awesome Skills (Skill Metadata Reference)
   - Original Author: sickn33
   - Link: https://github.com/sickn33/antigravity-awesome-skills

3. UI/UX Pro Max (Design Philosophy Reference)
   - Original Author: sickn33
   - Link: https://github.com/sickn33/ui-ux-pro-max

4. Model Context Protocol (MCP) standards
   - Authors: Anthropic & Ecosystem Contributors
   - Link: https://modelcontextprotocol.io/

5. High-Performance Web Standards
   - Inspiration: Vercel Engineering & Anthony Fu (antfu)

6. Strategic Knowledge Extraction
   - Inspiration: Fabric Patterns (danielmiessler)

*Note: All trademarks and copyrights belong to their respective owners. 
The references above reflect research-level inspiration and antecedent 
contributions. These parties are not involved in the management of this repository.*



# Mega AI Hub resource metadata

Creator / publisher: Dokhacgiakhoa
Original project: https://github.com/Dokhacgiakhoa/antigravity-ide/blob/c4a059bbf7a8d6b2162071f0fbfe74053faa6d20/.agent/skills/agent-tool-builder/SKILL.md
Attribution basis: Source repository record

Fields of work: Development & Engineering, Product Management
Roles: Data Engineer, Growth Product Manager, ML / AI Engineer, Product Manager, Technical Product Manager
Specialties: API
Tools: Json Schema
Country applicability: Country not specified
Classification basis: Source catalog labels
Instruction SHA-256: 533aa3da37957eb15b791d784ed9687dd4a59d50ab1d0f30cd8b19906d1c1cd6