novuhq/novu
Novu is an open-source communication infrastructure that unifies notification delivery across various channels for both products and AI agents, offering a single API for multi-channel messaging, wo...
Awesome AI Agents › Communication Protocols
a2aproject/a2a-java
The A2A Java SDK is the Java implementation of the Agent2Agent protocol, an open specification for interoperability between independently built agents. The repository is a multi-module Maven project that splits into client support, which lets Java code call any A2A-compliant agent regardless of the language it was written in, and server support, which wraps an existing agentic Java application so that other agents can discover and invoke it. Three transports are covered by reference implementations: JSON-RPC, gRPC and HTTP with JSON, and applications pick one by adding the matching reference artifact as a dependency. The gRPC layer is generated from the protocol buffer definition kept in the upstream A2A specification repository, with a dedicated module that regenerates the stubs when the specification changes. Java 17 or later is required. The reference server implementations are built on Quarkus, while a community integration provides support for any runtime implementing the Jakarta EE Web Profile, and the contribution guide describes how to add further runtime integrations. An extras area holds optional add-ons that matter in production deployments: OpenTelemetry instrumentation, a task store backed by JPA so agent task state survives restarts, a Kafka-based replicated queue manager for distributing event queues across instances, and alternative HTTP clients for Vert.x and Android. Worked examples pair a Java server with a Python client and a Java client with a Python server, demonstrating cross-language interoperability, and further agent samples live in the shared a2a-samples repository. Documentation is published as a separate site with server and client guides. The project is licensed under Apache 2.0 and is aimed at enterprise Java teams that want their services to participate in multi-agent systems using a standard protocol rather than bespoke integrations.
https://github.com/a2aproject/a2a-java
Also in Communication Protocols
google-agentic-commerce/AP2
Agent Payments Protocol (AP2) is a project focused on creating a secure and interoperable protocol for AI-driven payments, providing code samples and demos to facilitate development and integration.
a2aproject/a2a-samples
Official sample repository for the Agent2Agent (A2A) protocol, with runnable agent and host implementations in Python, Go, Java, JavaScript and C# built on the official A2A SDKs.
agent-network-protocol/AgentNetworkProtocol
AgentNetworkProtocol (ANP) is an open-source protocol designed to enable secure, decentralized, and efficient communication and collaboration among intelligent agents, aiming to become the HTTP of the Agentic Web era.
universal-tool-calling-protocol/python-utcp
Python reference implementation of the Universal Tool Calling Protocol, a plugin-based standard that lets agents discover and call existing tools directly over HTTP, SSE, CLI and other transports.
google-agentic-commerce/a2a-x402
Specification and reference libraries for the x402 extension to the Agent-to-Agent protocol, letting one agent charge another for a service through on-chain stablecoin payments in a three-message flow.
a2aproject/a2a-go
Go SDK for the Agent2Agent (A2A) protocol that provides client and server libraries for exposing and consuming agents over gRPC, REST and JSON-RPC, together with a CLI for discovery and messaging.
thu-nics/C2C
Research implementation of Cache-to-Cache, a method that lets two large language models exchange semantics directly by projecting and fusing their KV-caches instead of passing generated text between them.