Alternatives to Pydantic AI

Open-source AI agent SDK for production-grade Python & TypeScript agents

Microsoft's framework for building production-grade agentic AI on Azure, with Python, C#, and Go SDKs and a GA Agent Harness runtime.

Microsoft's open-source SDK for building production-grade AI agents with plugins, memory, and orchestration.

Hugging Face's barebones Python library for AI agents that act by writing code.

Go-native LLM framework by ByteDance for building production-grade AI applications.

Open-source Python framework turning messy text into typed, queryable Semantic DataFrames

Build AI agents on small language models—run locally or via any OpenAI-compatible server.

An open-source Python framework that turns ordinary functions into AI-powered tools via simple decorators.

Open-source Python SDK for building multi-agent workflows with handoffs, guardrails, and sandboxing

Simulation-based AI agent testing that catches hallucinations before production

Open AI toolkit for loyal, auditable coding agents.

Durable execution for workflows & AI agents — no queues or infrastructure

Open-source TypeScript framework for building durable, observable AI agents and workflows.

Developer-first platform to connect APIs, AI, and databases via workflows and agents.

Open-source TypeScript toolkit for building AI apps with 100+ models, streaming, and agent support

Open-source Python library for guaranteed valid structured outputs from LLMs

An open-source Python library for steering LLMs with native control flow, regex, and CFG constraints.

A type-safe programming language for building AI agents with compile-time guarantees on structured outputs.

Open-source LLM that turns natural language into API calls for tool-using agents

Build type-safe LLM agents in Rust with one unified provider API.

Google's open-source framework for building agentic AI apps in JS, Go, Python & Dart.

TypeScript SDK to build AI agents with composable middleware and full control.

Free, zero-knowledge browser markdown editor for prompt testing and multi-model comparison.

LMQL is a programming language for LLM interaction with typed constraints, nested queries, and multi-backend portability.

Deterministic, typed AI workflow DSL with Git-versioned .mthds files

Interactive 470-page ebook for building production LLM apps with Colab notebooks.

React frontend stack for building agentic user experiences with generative UI

Agentic AI for the entire DevSecOps lifecycle in GitLab.

Open-source agentic AI data assistant for SQL, code, and reports

Build LLM apps with decorators, observability, and full control.