Can I use this with Pydantic for validation?

Yes, the skill includes specific implementation patterns for using Pydantic models to define schemas and automatically parse structured outputs into typed objects.

What is LLM function calling?

LLM function calling is a mechanism that allows an AI model to request the execution of predefined code functions to interact with external systems or retrieve real-time data.

How does this skill handle parallel tool calls?

It provides async patterns to execute multiple tool requests concurrently using asyncio, which reduces latency when an LLM needs to gather information from multiple sources at once.

What is a tool execution loop?

A tool execution loop is a process where the LLM calls tools, receives their output, and then uses that information to decide whether to call more tools or provide a final answer.

Why use strict mode in tool definitions?

Strict mode ensures the LLM generates JSON that matches your defined schema exactly, preventing hallucinations of extra fields and significantly reducing parsing errors.

LLM Function Calling & Tool Use

Name: LLM Function Calling & Tool Use
Author: yonatangross

byyonatangross

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Data Science & ML

Enables LLMs to interact with external tools and return structured data through standardized function calling patterns and strict schemas.

This skill provides a comprehensive framework for implementing LLM tool usage, focusing on 2026 best practices like strict schema validation and structured outputs. It covers the entire lifecycle of function calling—from defining robust tool schemas and managing asynchronous execution loops to handling parallel calls and parsing typed responses with Pydantic. By implementing these patterns, developers can build more reliable autonomous agents and complex AI-driven workflows that interact seamlessly with external APIs and databases.

Key Features

01Asynchronous tool execution loops with automated result routing

0269 GitHub stars

03Native LangChain tool binding and structured output integration

04Typed structured output validation using Pydantic and Zod

052026 strict mode tool definition patterns for guaranteed schema compliance

06Parallel tool call orchestration for high-performance concurrent execution

Use Cases

01Extracting typed, validated JSON data from unstructured natural language inputs

02Implementing multi-step reasoning loops where the LLM executes multiple tools concurrently

03Building autonomous agents that interact with external APIs, databases, and file systems

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add yonatangross/orchestkit function-calling

For use in Claude.ai and ChatGPT

Download Skill