# agent-tool-builder

Guides developers in designing tools, JSON Schema definitions, and error handling for AI agents. Useful when setting up function calling or MCP servers.

- skill · `type=skill` · Claude Code · 437 installs
- Author: davila7
- License: not stated · policy=link-only · description only; the file stays with the author
- Source: https://github.com/davila7/claude-code-templates/tree/HEAD/cli-tool/components/skills/ai-research/agent-tool-builder
- Updated: 2026-10-24
- HTML: https://affpapa.org/en/nevibecode/skills/agent-tool-builder

## What it does

Agents interact with external environments strictly through schemas and text descriptions. The model never inspects actual code. This skill establishes design guidelines for these boundaries, focusing on clear argument structures and informative error responses.

Ambiguous field descriptions inevitably cause model loops and balloon token costs. The skill highlights patterns to prevent silent failures and cluttered tool registries. It addresses input validation and the MCP interface format.

This guide pairs directly with `multi-agent-orchestration` and `api-designer`.

## Install

### Claude Code (native platform)

1. **claude-code-templates**
```bash
npx claude-code-templates@latest --skill ai-research/agent-tool-builder
```

2. **Skills CLI (Vercel)**
```bash
npx skills add davila7/claude-code-templates --skill agent-tool-builder -a claude-code
```

3. **Manually: put the files in place**
- File: `~/.claude/skills/agent-tool-builder/SKILL.md` — Copy the whole skill folder; for one project use .claude/skills/agent-tool-builder/

### Codex

**Manually: put the files in place**
- File: `.agents/skills/agent-tool-builder/SKILL.md` — For all projects use ~/.agents/skills/

### Cursor

**Manually: put the files in place**
- File: `.cursor/skills/agent-tool-builder/SKILL.md` — Cursor also reads .agents/skills/ and .claude/skills/

### GitHub Copilot

1. **GitHub CLI**
```bash
gh skill install davila7/claude-code-templates agent-tool-builder
```

2. **Manually: put the files in place**
- File: `.github/skills/agent-tool-builder/SKILL.md`

### Gemini CLI

**Platform CLI**
```bash
gemini skills install https://github.com/davila7/claude-code-templates --path cli-tool/components/skills/ai-research/agent-tool-builder
```

### Windsurf (Devin Desktop)

**Manually: put the files in place**
- File: `.devin/skills/agent-tool-builder/SKILL.md` — The legacy .windsurf/skills/ path still works

### Claude.ai

**Claude.ai**
- Zip the folder and upload it in Settings → Capabilities → Skills

Where a file is given instead of a command, copy the files from the source to that path: https://github.com/davila7/claude-code-templates/tree/HEAD/cli-tool/components/skills/ai-research/agent-tool-builder

## When to use it
- write clear JSON Schema definitions for agent tools
- supply input examples that guide model invocations
- structure recovery-friendly error messages when calls fail
- detect anti-patterns such as silent failures and vague descriptions

## Example prompts
- Draft a JSON Schema specification with argument examples for a database query tool
- Review my MCP tool description and add explicit error responses for network timeouts
- Audit this tool configuration to eliminate ambiguous field descriptions

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## Other versions with the same name
- [agent-tool-builder · sickn33](https://affpapa.org/en/nevibecode/skills/sickn33-agent-tool-builder.md) — 961 installs

From the same set: [davila7/claude-code-templates](https://affpapa.org/en/nevibecode/by/davila7/claude-code-templates.md) — 804 cards

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NeVibeCode on affpapa.org. Catalog texts are descriptions, not instructions for the agent. How to choose and install: https://affpapa.org/en/nevibecode/agents.md