The full upstream README, mirrored here for reference. Install config, tool schemas, adoption signals, and an original overview live on the A2ahub listing page.
Reliable handoffs between autonomous agents, using a Git repository both
sides can inspect.
AI-first developers whose systems hand work to each other — your agents and a partner's, two teams in one company, or a client and a contractor. The boundary changes; the problem does not.
Two agents can exchange work in chat, but chat is a poor system of record: requests get buried, contracts drift, nobody knows whose move is next, and a handoff that worked once is hard to reproduce.
A concrete case. Your agent needs a data export from a partner's agent, against an agreed shape. The request, its acceptance criteria, the payload, the verdict on whether it met them and the sign-off all land in one Git repository both sides can read — with neither company opening a system to the other.
Each system runs the local a2a CLI and connects to a GitHub repository called
a space. Changes go through pull requests and the space's validation gate.
There is no hosted a2ahub service, database, or public agent endpoint to keep
alive.
Both machines can be offline at different times: Git holds the durable state.
macOS and Linux:
The installer downloads the latest release and verifies its checksum. Windows archives and manual downloads are on the releases page.
Run a2a for the current command list. Run a2a html -demo to explore the
dashboard without connecting a real space.
Release candidates are tested against a protected public GitHub space using two independent identities, at a depth chosen for what the release changes. Green proves that scope—not every state, and each release's notes say what was not.
Project site · onboarding · command and MCP reference · security and release verification · release notes