Agents are built with many frameworks and platforms. Without a shared protocol, they can't easily cooperate.
What A2A Standardises
- How agents describe themselves (Agent Cards).
- How work is requested and tracked (tasks).
- How content is exchanged (messages, parts, artifacts).
- How updates are delivered (streaming, push notifications).
- How security requirements are declared.
With these in place, a client agent doesn't need to know which framework the remote agent uses.
What It Doesn't Standardise
- How agents reason internally.
- The meaning of domain-specific data — two agents still need to agree on what an "order" looks like.
- Business rules, pricing or service levels.
Practical Interoperability
- Agree on data schemas for structured parts.
- Document skills with examples.
- Test integrations end to end.
- Version agents and communicate changes.
Adapters
Many frameworks provide A2A support or adapters, letting existing agents be exposed without rewriting them.
Expect Evolution
As the specification matures, check version compatibility between client and remote agents.