feat: Add url_context_tool

PiperOrigin-RevId: 767747328

Author: google-genai-bot

src/google/adk/tools/__init__.py

@@ -27,13 +27,15 @@
 from .preload_memory_tool import preload_memory_tool as preload_memory
 from .tool_context import ToolContext
 from .transfer_to_agent_tool import transfer_to_agent
+from .url_context_tool import url_context
 from .vertex_ai_search_tool import VertexAiSearchTool
 
 __all__ = [
     'APIHubToolset',
     'AuthToolArguments',
     'BaseTool',
     'google_search',
+    'url_context',
     'VertexAiSearchTool',
     'ExampleTool',
     'exit_loop',

src/google/adk/tools/url_context_tool.py

@@ -0,0 +1,61 @@
+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+from google.genai import types
+from typing_extensions import override
+
+from .base_tool import BaseTool
+from .tool_context import ToolContext
+
+if TYPE_CHECKING:
+  from ..models import LlmRequest
+
+
+class UrlContextTool(BaseTool):
+  """A built-in tool that is automatically invoked by Gemini 2 models to retrieve content from the URLs and use that content to inform and shape its response.
+
+  This tool operates internally within the model and does not require or perform
+  local code execution.
+  """
+
+  def __init__(self):
+    # Name and description are not used because this is a model built-in tool.
+    super().__init__(name='url_context', description='url_context')
+
+  @override
+  async def process_llm_request(
+      self,
+      *,
+      tool_context: ToolContext,
+      llm_request: LlmRequest,
+  ) -> None:
+    llm_request.config = llm_request.config or types.GenerateContentConfig()
+    llm_request.config.tools = llm_request.config.tools or []
+    if llm_request.model and 'gemini-1' in llm_request.model:
+      raise ValueError('Url context tool can not be used in Gemini 1.x.')
+    elif llm_request.model and 'gemini-2' in llm_request.model:
+      llm_request.config.tools.append(
+          types.Tool(url_context=types.UrlContext())
+      )
+    else:
+      raise ValueError(
+          f'Url context tool is not supported for model {llm_request.model}'
+      )
+
+
+url_context = UrlContextTool()