atmosphere

Real-time transport layer for Java AI agents. Build once with @Agent — deliver over WebSocket, SSE, gRPC, and WebTransport/HTTP3. Talk MCP, A2A and AG-UI. Maintained by Atmosphere on GitHub, where it has earned 3,785 stars from the community.

It's actively developed around acp, agentic-ai, embabel, and is a solid reference for anyone building with these tools.