From 1e23652968164c5fdfa5564e966e78799237d94b Mon Sep 17 00:00:00 2001
From: George Weale <gweale@google.com>
Date: Sun, 7 Sep 2025 18:37:01 -0700
Subject: [PATCH] fix: AttributeError and indentation in parameter processing.
 For issue #2776 and issue #2763

PiperOrigin-RevId: 804222317
---
 src/google/adk/models/lite_llm.py      |   9 +-
 tests/unittests/models/test_litellm.py | 127 +++++++++++++++++++++++++
 2 files changed, 133 insertions(+), 3 deletions(-)

diff --git a/src/google/adk/models/lite_llm.py b/src/google/adk/models/lite_llm.py
index d84df9ab..f25f0cdb 100644
--- a/src/google/adk/models/lite_llm.py
+++ b/src/google/adk/models/lite_llm.py
@@ -392,7 +392,10 @@ def _function_declaration_to_tool_param(
       },
   }
 
-  if function_declaration.parameters.required:
+  if (
+      function_declaration.parameters
+      and function_declaration.parameters.required
+  ):
     tool_params["function"]["parameters"][
         "required"
     ] = function_declaration.parameters.required
@@ -596,8 +599,8 @@ def _get_completion_inputs(
         mapped_key = param_mapping.get(key, key)
         generation_params[mapped_key] = config_dict[key]
 
-      if not generation_params:
-        generation_params = None
+    if not generation_params:
+      generation_params = None
 
   return messages, tools, response_format, generation_params
 
diff --git a/tests/unittests/models/test_litellm.py b/tests/unittests/models/test_litellm.py
index a7152f55..a46d0f7d 100644
--- a/tests/unittests/models/test_litellm.py
+++ b/tests/unittests/models/test_litellm.py
@@ -731,6 +731,52 @@ function_declaration_test_cases = [
             },
         },
     ),
+    (
+        "no_parameters",
+        types.FunctionDeclaration(
+            name="test_function_no_params",
+            description="Test function with no parameters",
+        ),
+        {
+            "type": "function",
+            "function": {
+                "name": "test_function_no_params",
+                "description": "Test function with no parameters",
+                "parameters": {
+                    "type": "object",
+                    "properties": {},
+                },
+            },
+        },
+    ),
+    (
+        "parameters_without_required",
+        types.FunctionDeclaration(
+            name="test_function_no_required",
+            description="Test function with parameters but no required field",
+            parameters=types.Schema(
+                type=types.Type.OBJECT,
+                properties={
+                    "optional_arg": types.Schema(type=types.Type.STRING),
+                },
+            ),
+        ),
+        {
+            "type": "function",
+            "function": {
+                "name": "test_function_no_required",
+                "description": (
+                    "Test function with parameters but no required field"
+                ),
+                "parameters": {
+                    "type": "object",
+                    "properties": {
+                        "optional_arg": {"type": "string"},
+                    },
+                },
+            },
+        },
+    ),
 ]
 
 
@@ -1577,6 +1623,87 @@ def test_get_completion_inputs_generation_params():
   assert "stop_sequences" not in generation_params
 
 
+@pytest.mark.asyncio
+def test_get_completion_inputs_empty_generation_params():
+  # Test that generation_params is None when no generation parameters are set
+  req = LlmRequest(
+      contents=[
+          types.Content(role="user", parts=[types.Part.from_text(text="hi")]),
+      ],
+      config=types.GenerateContentConfig(),
+  )
+  from google.adk.models.lite_llm import _get_completion_inputs
+
+  _, _, _, generation_params = _get_completion_inputs(req)
+  assert generation_params is None
+
+
+@pytest.mark.asyncio
+def test_get_completion_inputs_minimal_config():
+  # Test that generation_params is None when config has no generation parameters
+  req = LlmRequest(
+      contents=[
+          types.Content(role="user", parts=[types.Part.from_text(text="hi")]),
+      ],
+      config=types.GenerateContentConfig(
+          system_instruction="test instruction"  # Non-generation parameter
+      ),
+  )
+  from google.adk.models.lite_llm import _get_completion_inputs
+
+  _, _, _, generation_params = _get_completion_inputs(req)
+  assert generation_params is None
+
+
+@pytest.mark.asyncio
+def test_get_completion_inputs_partial_generation_params():
+  # Test that generation_params is correctly built even with only some parameters
+  req = LlmRequest(
+      contents=[
+          types.Content(role="user", parts=[types.Part.from_text(text="hi")]),
+      ],
+      config=types.GenerateContentConfig(
+          temperature=0.7,
+          # Only temperature is set, others are None/default
+      ),
+  )
+  from google.adk.models.lite_llm import _get_completion_inputs
+
+  _, _, _, generation_params = _get_completion_inputs(req)
+  assert generation_params is not None
+  assert generation_params["temperature"] == 0.7
+  # Should only contain the temperature parameter
+  assert len(generation_params) == 1
+
+
+def test_function_declaration_to_tool_param_edge_cases():
+  """Test edge cases for function declaration conversion that caused the original bug."""
+  from google.adk.models.lite_llm import _function_declaration_to_tool_param
+
+  # Test function with None parameters (the original bug scenario)
+  func_decl = types.FunctionDeclaration(
+      name="test_function_none_params",
+      description="Function with None parameters",
+      parameters=None,
+  )
+  result = _function_declaration_to_tool_param(func_decl)
+  expected = {
+      "type": "function",
+      "function": {
+          "name": "test_function_none_params",
+          "description": "Function with None parameters",
+          "parameters": {
+              "type": "object",
+              "properties": {},
+          },
+      },
+  }
+  assert result == expected
+
+  # Verify no 'required' field is added when parameters is None
+  assert "required" not in result["function"]["parameters"]
+
+
 def test_gemini_via_litellm_warning(monkeypatch):
   """Test that Gemini via LiteLLM shows warning."""
   # Ensure environment variable is not set