agentplatform: a2a_tasks and a2a_task_events reference types missing from agentplatform._genai.types #7246

agentplatform/_genai/a2a_tasks.py and agentplatform/_genai/a2a_task_events.py (copies of the vertexai._genai modules) reference types.A2aTask, types.TaskEvent, types.{Create,Get,Delete,List}AgentEngineTaskConfigOrDict, types.{Append,List}AgentEngineTaskEvent* and the _*AgentEngineTask*RequestParameters models, but agentplatform._genai.types defines none of them; only vertexai._genai.types does. Still the case in 2.6.0 (2026-10-20).

Environment details

• OS type and version: any (the names are missing from the published wheel; seen on FreeBSD 15.1)
• Python version: 3.12, 3.13 and 3.14
• google-cloud-aiplatform version: 2.6.0 (also 2.4.0 and 2.5.0)

Steps to reproduce

1. pip install "google-cloud-aiplatform[agent_engines]"
2. python3.13 -c "import agentplatform._genai.a2a_tasks"

Actual result

• Python 3.12 / 3.13: AttributeError: module 'agentplatform._genai.types' has no attribute 'DeleteAgentEngineTaskConfigOrDict' (and ... 'TaskEventOrDict' for a2a_task_events).
• Python 3.14 (lazy annotations): the import works, but every method fails, e.g. AttributeError: ... '_GetAgentEngineTaskRequestParameters'.

Expected result

Both modules import and work, as their vertexai._genai counterparts do.

Notes

The whole A2A task family is missing from agentplatform/_genai/types/common.py: about 80 definitions, including the *Dict / *OrDict / enum types the models depend on (A2aTaskState, TaskOutput, TaskArtifact, TaskStatusDetails, ...). Every name the two modules use is already defined in vertexai/_genai/types/common.py. Copying those definitions unchanged into the agentplatform types (and exporting them from __init__.py the way vertexai does) fixes both modules; with that change, a mocked A2aTasks get() / delete() / .events smoke test passes on 3.12, 3.13 and 3.14.

These files say they are produced by the Gen AI SDK generator, so the fix probably belongs in the agentplatform types generation (or, if these modules aren't meant to be exposed in agentplatform, in not generating a2a_tasks.py / a2a_task_events.py there; nothing in agentplatform imports them).