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

# What's New

> Latest features and improvements in ACP

* **🧭 [Trajectory Metadata](/core-concepts/message-metadata#trajectory-metadata)** – Enhanced MessagePart with TrajectoryMetadata for improved tracking of multi-step reasoning and tool usage. Enables agents to expose their internal reasoning paths, tool invocation chains, and state transitions across a conversation, supporting advanced debugging and interpretability workflows.

* **🌐 [Distributed Sessions](/core-concepts/distributed-sessions)** - Session continuity across multiple server instances using URI-based resource sharing. This enables agents to maintain conversation history and state even when requests are handled by different server nodes, without requiring centralized storage infrastructure.

* **🔍 [RAG LlamaIndex Agent](https://github.com/i-am-bee/acp/tree/main/examples/python/llama-index-rag)** - New example agent demonstrating Retrieval-Augmented Generation (RAG) using LlamaIndex. Shows how to build knowledge-based agents that can query external documents and provide contextually relevant responses.

* **📚 [Citation Metadata](/core-concepts/message-metadata#citation-metadata)** - Enhanced MessagePart with CitationMetadata for improved source tracking and attribution. Enables agents to provide transparent references to their information sources, improving trustworthiness and enabling fact-checking workflows.

* **⚡ [High Availability Support](/how-to/high-availability)** - Deploy ACP servers with centralized storage backends (Redis/PostgreSQL) for scalable, fault-tolerant setups. Enables production deployments with multiple server instances, load balancing, and automatic failover capabilities.

* **📝 [Message Role Parameter](/core-concepts/message-structure)** - Added `role` parameter to Message structure for better agent identification. Supports `user`, `agent`, and `agent/{name}` formats, enabling clearer conversation tracking and multi-agent coordination.

* **🔄 [TypeScript SDK (Client)](https://github.com/i-am-bee/acp/tree/main/typescript)** - Full TypeScript client library for interacting with ACP agents. Provides type-safe client implementations with comprehensive support for all ACP operations including sessions, runs, and streaming.

## Get Involved

ACP is an open-source project and we welcome contributions! Whether you're reporting bugs, suggesting features, or contributing code, check out our [contribution guidelines](/about/contribute) to get started.