From 58d6e75f797aed38fe69072dd536a6772f70428f Mon Sep 17 00:00:00 2001
From: zhangzherui <jerry_@whut.edu.cn>
Date: Thu, 23 Jul 2026 02:50:34 +0800
Subject: [PATCH] fix(a2a): Support instruction providers in cards

Agent cards are static and have no ReadonlyContext, so passing callable instructions into description or example regexes crashes card generation. Include only static strings and leave runtime providers unexecuted.

Fixes #6450
---
 .../a2a/utils/test_agent_card_builder.py      | 48 +++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/tests/unittests/a2a/utils/test_agent_card_builder.py b/tests/unittests/a2a/utils/test_agent_card_builder.py
index 590a29b6b2..6914f736d3 100644
--- a/tests/unittests/a2a/utils/test_agent_card_builder.py
+++ b/tests/unittests/a2a/utils/test_agent_card_builder.py
@@ -13,6 +13,7 @@
 # limitations under the License.
 
 import json
+from unittest.mock import AsyncMock
 from unittest.mock import Mock
 from unittest.mock import patch
 
@@ -360,6 +361,53 @@ async def test_build_omits_instructions_from_card(self):
     )
     assert primary_skill["description"] == "Writes a short reply."
 
+  async def test_build_omits_sync_instruction_provider(self):
+    """A static card omits a sync instruction that needs runtime context."""
+    instruction_provider = Mock(return_value="You use runtime context.")
+    agent = LlmAgent(
+        name="provider_agent",
+        description="Uses runtime instructions.",
+        instruction=instruction_provider,
+    )
+
+    card = await AgentCardBuilder(agent=agent).build()
+
+    assert card.skills[0].description == "Uses runtime instructions."
+    instruction_provider.assert_not_called()
+
+  async def test_build_omits_async_instruction_provider(self):
+    """A static card omits an async instruction that needs runtime context."""
+    instruction_provider = AsyncMock(
+        return_value="You use async runtime context."
+    )
+    agent = LlmAgent(
+        name="async_provider_agent",
+        description="Uses async runtime instructions.",
+        instruction=instruction_provider,
+    )
+
+    card = await AgentCardBuilder(agent=agent).build()
+
+    assert card.skills[0].description == "Uses async runtime instructions."
+    instruction_provider.assert_not_called()
+
+  async def test_build_omits_global_instruction_provider(self):
+    """A static card omits a global instruction that needs runtime context."""
+    global_instruction_provider = Mock(
+        return_value="You use global runtime context."
+    )
+    agent = LlmAgent(
+        name="global_provider_agent",
+        description="Answers questions.",
+        instruction="You answer user questions.",
+        global_instruction=global_instruction_provider,
+    )
+
+    card = await AgentCardBuilder(agent=agent).build()
+
+    assert card.skills[0].description == "Answers questions."
+    global_instruction_provider.assert_not_called()
+
   async def test_build_succeeds_for_workflow_with_llm_agent_node(self):
     """AgentCardBuilder.build succeeds for a Workflow (no sub_agents)."""
     writer = LlmAgent(