pypi / a2a-sdk

a2a-sdk

What changed in a2a-sdk 1, from its official release notes, upgrade guides and advisories. Sources checked 2026-10-24.

2 breaking1 new APIs and options17 fixes and other

See which of these apply to your code, ranked, in your agent:

npx @unstale/cli init

a2a-sdk 120 changes

Open containers count toward the nesting bound, so an empty container leaf is refused.
1.2.3release notes
Push URLs in shared address space are rejected.
1.2.3release notes

The client ignores the patch version when preferring a 1.0 interface.
1.2.3release notes
The server releases the ActiveTask after a direct Message response.
1.2.3release notes
Malformed agent card parsing errors are normalized.
1.2.3release notes
The server warns when an AgentCard is missing required fields.
1.2.3release notes
Follow-up messages run in the sender's contextvars.
1.2.3release notes
For v0.3 JSON-RPC and REST, a history_length of 0 is treated as unlimited.
1.2.3release notes
Internal lifecycle events are marked done so a cancelled stream frees its producer.
1.2.3release notes
Push notification failures are isolated from the task lifecycle.
1.2.3release notes
trace_function alone decides a span's status.
1.2.3release notes
A v0.3 gRPC or REST send without configuration blocks.
1.2.3release notes
An unset v0.3 history_length is now treated as unlimited.
1.2.2release notes
Malformed JSON-RPC bodies no longer print a traceback to stderr.
1.2.2release notes
Creating a push notification config now returns the stored id.
1.2.2release notes
The client now handles REST error bodies that are not a google.rpc.Status.
1.2.2release notes
Terminal-state errors now name the task state.
1.2.2release notes
The conversion now keeps the timestamp and three other fields.
1.2.2release notes
ListTasks page tokens now use keyset cursors.
1.2.1release notes