What is strict tool mode in Claude?

Strict tool mode is a feature that ensures the tool parameters generated by Claude exactly match your provided JSON schema, preventing validation errors during execution.

When should I use this over the json-outputs-implementer skill?

Use Strict Tool Implementer for building agents that need to call functions or tools. Use the json-outputs-implementer for data extraction, classification, or formatting text into JSON.

Which Claude models support this skill?

This skill is designed for models that support structured outputs, such as Claude 3.5 Sonnet and Claude 3 Opus, utilizing the latest beta headers.

Are there limitations to the schemas I can use?

Yes, while it supports basic types and enums, strict mode currently does not support recursive schemas, complex regex, or certain min/max constraints.

Does this skill help with manual parameter validation?

Actually, it removes the need for it. By using strict mode, the parameters are guaranteed to match your schema before they reach your function, simplifying your codebase.

Strict Tool Implementer

Name: Strict Tool Implementer
Author: cskiro

bycskiro

•

API開発

Implements Anthropic's strict tool use mode to guarantee schema compliance in multi-step agentic workflows.

The Strict Tool Implementer skill enables developers to build reliable, production-grade agentic systems by leveraging Anthropic's strict tool use mode. By enforcing the strict: true parameter, it ensures that tool input parameters perfectly match defined schemas, eliminating the need for manual validation within tool functions. This skill provides a comprehensive framework covering schema design, multi-tool orchestration, error handling, and testing patterns specifically for high-stakes operations requiring guaranteed type safety and predictable model behavior.

主な機能

012 GitHub stars

02Robust error handling and production monitoring patterns

03Production-ready tool schema design with guaranteed compliance

04Multi-tool agentic workflow architecture and composition

05Type-safe tool execution without manual input validation

06Comprehensive testing strategies for agentic workflows

ユースケース

01Creating type-safe interfaces for LLM-driven internal tools

02Building multi-step agents for complex task automation

03Implementing tool calling for critical financial or infrastructure operations

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add cskiro/claudex strict-tool-implementer

For use in Claude.ai and ChatGPT

Download Skill