From 8a400141c5477e3b06fdaae082112dd014996f54 Mon Sep 17 00:00:00 2001
From: Yufeng He <40085740+he-yufeng@users.noreply.github.com>
Date: Wed, 20 May 2026 03:39:10 +0800
Subject: [PATCH] fix: accept Azure assistant file ids

---
 src/google/adk/models/lite_llm.py      |  2 +-
 tests/unittests/models/test_litellm.py | 14 ++++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/google/adk/models/lite_llm.py b/src/google/adk/models/lite_llm.py
index 4d4f93c88f..623b9ea338 100644
--- a/src/google/adk/models/lite_llm.py
+++ b/src/google/adk/models/lite_llm.py
@@ -281,7 +281,7 @@ def _infer_mime_type_from_uri(uri: str) -> Optional[str]:
 
 def _looks_like_openai_file_id(file_uri: str) -> bool:
   """Returns True when file_uri resembles an OpenAI/Azure file id."""
-  return file_uri.startswith("file-")
+  return file_uri.startswith(("file-", "assistant-"))
 
 
 def _is_http_url(uri: str) -> bool:
diff --git a/tests/unittests/models/test_litellm.py b/tests/unittests/models/test_litellm.py
index 216866602f..a85a3e5caa 100644
--- a/tests/unittests/models/test_litellm.py
+++ b/tests/unittests/models/test_litellm.py
@@ -2943,6 +2943,20 @@ async def test_get_content_file_uri_file_id_required_preserves_file_id(
   assert content == [{"type": "file", "file": {"file_id": "file-abc123"}}]
 
 
+@pytest.mark.asyncio
+async def test_get_content_file_uri_azure_preserves_assistant_file_id():
+  parts = [
+      types.Part(
+          file_data=types.FileData(
+              file_uri="assistant-abc123",
+              mime_type="application/pdf",
+          )
+      )
+  ]
+  content = await _get_content(parts, provider="azure", model="azure/gpt-4.1")
+  assert content == [{"type": "file", "file": {"file_id": "assistant-abc123"}}]
+
+
 @pytest.mark.asyncio
 @pytest.mark.parametrize(
     "provider,model",