Agent2Agent Protocol · Endpoint removal
The A2A v0.3 method naming is deprecated
Deprecated, no date
Agent2Agent Protocol deprecated A2A calls message/*, tasks/*, agent/* without giving a shutdown date yet.
What to use instead of these calls
Send the v1.0 names: message/send becomes SendMessage, message/stream SendStreamingMessage, tasks/get GetTask, tasks/cancel CancelTask, tasks/resubscribe SubscribeToTask, agent/getAuthenticatedExtendedCard GetExtendedAgentCard, tasks/pushNotificationConfig/set CreateTaskPushNotificationConfig. v1.0 changes the messages too: one Part type (mediaType for mimeType), no kind field, TASK_STATE_* and ROLE_* values, and the A2A-Version: 1.0 header.
The v1.0 names work only on an agent that serves A2A 1.0 (its agent card lists a 1.0 interface), which the calling code does not tell, and v1.0 changes the messages too: the team decides.
Calls it hits
A2A calls message/*, tasks/*, agent/*
RENAMED: Operation now SendMessage
Facts
- API
- Agent2Agent Protocol
a2a-protocol.org - Kind
- Endpoint removal
- Announced
- March 12, 2026
- Takes effect
- No date given yet
- Calls after that day
- Fail
- Source
- Announcement
- Last updated
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