From 180a011d5b5b84c076d3c8aff7493d08a8a38f5d Mon Sep 17 00:00:00 2001
From: Dani Zamora <60208642+danielazamorah@users.noreply.github.com>
Date: Mon, 17 Aug 2026 12:57:55 -0600
Subject: [PATCH] docs: Known Issues: A2A Workflow Output Schema and
 Serialization

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+# Known Issues: A2A Workflow Output Schema and Serialization
+
+## Discarded Workflow `output_schema` in `to_a2a()`
+
+When a `Workflow` with a configured `output_schema` is exposed over the Agent-to-Agent (A2A) protocol via `to_a2a()`:
+- The final structured object validated against `output_schema` may not be placed into the A2A response artifact.
+- Instead, the artifact may only contain the raw text output of the last executed agent node.
+
+## Schema Validation Serialization Mode
+
+In `BaseNode._validate_schema`, validated Pydantic `BaseModel` instances are converted using `model_dump()` in Pydantic Python mode rather than JSON mode. Fields containing non-primitive types (such as `Decimal`, `datetime`, or `UUID`) are preserved as Python objects and can cause serialization errors when downstream components attempt standard JSON serialization.
+
+## Relayed Human-Input Responses
+
+When a remote agent pauses for user confirmation or input (e.g., `adk_request_confirmation`) and relays the pause to the caller:
+- Responding to the pause in `RemoteA2aAgent` may flatten the human response into a plain text message rather than forwarding a `FunctionResponse` matching the tool call name.
+- This can prevent the remote paused agent from recognizing completion of the requested confirmation.
+
+*Note: Maintainer verification is required regarding planned upstream fixes for A2A artifact output mapping and relayed function response preservation.*