> ## Documentation Index
> Fetch the complete documentation index at: https://docs.instructorphp.com/llms.txt
> Use this file to discover all available pages before exploring further.

# V1.6.0

### Major Features

* **Chat Architecture** - Multi-participant chat mechanism with conversation coordination, and automatic summaries
* **ReAct Tool Use** - New ReAct (Reasoning and Acting) driver for advanced tool-based reasoning patterns alongside existing tool calling capabilities
* **Script System Refactoring** - Script functionality moved from templates to dedicated messages package with enhanced rendering capabilities

### Chat System

* **Multi-Participant Chats** - Support for multiple LLM participants, human participants, and tool-equipped agents in conversation flows
* **Chat Coordination** - Built-in coordinators including LLM-based, tool-based, and round-robin participant selection
* **Conversation Summaries** - Automatic chat summarization with configurable buffering and context management
* **Chat State Management** - Comprehensive state tracking with steps, outcomes, and continuation criteria
* **Chat Events** - Complete event system for monitoring chat lifecycle, participant selection, and tool usage

### Tool Use Enhancements

* **ReAct Driver** - New reasoning and acting pattern for more sophisticated tool use with decision tracking
* **Tool Calling Refactoring** - Enhanced tool calling driver with improved error handling and execution flow
* **Tool Execution Formatting** - Better formatting and display of tool execution results
* **Multiple Driver Support** - Clean separation between ReAct and tool calling approaches

### Architecture Improvements

* **Messages Package** - Script system relocated from templates to messages package for better separation of concerns
* **Rendering System** - New arrow-pipe messages renderer and role-based rendering capabilities
* **Time Management** - Added clock interfaces for better testability and time-dependent operations
* **Continuation Criteria** - Enhanced continuation logic with token limits, execution time limits, and step limits

### Core Enhancements

* **Structured Output** - Improved deserialization and streaming capabilities for structured data
* **HTTP Client** - Enhanced HTTP client handling with better error management
* **Documentation Testing** - Major Doctest architecture refactoring with improved code block extraction and validation
* **Cohere Integration** - Fixed max\_tokens parameter handling for Cohere API

### Bug Fixes

* **Property Info Adapter** - Enhanced compatibility with PropertyInfo v7 for better type introspection
* **Test Infrastructure** - Added comprehensive fake inference drivers and mock HTTP testing capabilities
* **Memory Management** - Improved memory handling in streaming and sequence processing

### Testing & Quality

* **Test Coverage** - New test suites for Chat, ToolUse, and Doctest functionality
* **Mock Infrastructure** - Enhanced testing infrastructure with fake drivers and HTTP mocking
* **Static Analysis** - Updated PHPStan and Psalm configurations for better code quality

### Documentation

* **Package Documentation** - Updated CHEATSHEET.md files across packages with comprehensive usage examples
* **Chat Documentation** - New dedicated documentation for chat and tool use patterns
* **Architecture Guides** - Enhanced OVERVIEW\.md files explaining package internals and design decisions

***

**Full Changelog**: [v1.5.0...v1.6.0](https://github.com/cognesy/instructor-php/compare/v1.5.0...v1.6.0)