Neuron AI is a PHP framework for building AI-powered applications with support for multiple large language model providers (OpenAI, Anthropic, Gemini, Mistral, Ollama, AWS Bedrock, etc.), tool integration, structured output, retrieval-augmented generation (RAG), and complex workflow orchestration. It provides a composable agent class that can operate in chat, stream, and structured output modes, a workflow engine with interrupt/resume and persistence, a built-in evaluation framework with LLM-based judges and assertions, and a Model Context Protocol (MCP) client for connecting to external tool servers. The architecture is modular: agents are built on top of workflows, tools are defined via PHP classes with JSON schema generation, and providers are abstracted behind a common interface with traits for shared logic.