refactor(config): move BaseToolConfig to a separate file

PiperOrigin-RevId: 791841562

Author: wuliang229

src/google/adk/agents/llm_agent.py

@@ -47,9 +47,9 @@
 from ..models.registry import LLMRegistry
 from ..planners.base_planner import BasePlanner
 from ..tools.base_tool import BaseTool
-from ..tools.base_tool import ToolConfig
 from ..tools.base_toolset import BaseToolset
 from ..tools.function_tool import FunctionTool
+from ..tools.tool_configs import ToolConfig
 from ..tools.tool_context import ToolContext
 from ..utils.feature_decorator import working_in_progress
 from .base_agent import BaseAgent

src/google/adk/agents/llm_agent_config.py

@@ -22,7 +22,7 @@
 from google.genai import types
 from pydantic import ConfigDict
 
-from ..tools.base_tool import ToolConfig
+from ..tools.tool_configs import ToolConfig
 from .base_agent_config import BaseAgentConfig
 from .common_configs import CodeConfig
 

src/google/adk/tools/agent_tool.py

@@ -28,8 +28,8 @@
 from ..memory.in_memory_memory_service import InMemoryMemoryService
 from ._forwarding_artifact_service import ForwardingArtifactService
 from .base_tool import BaseTool
-from .base_tool import BaseToolConfig
-from .base_tool import ToolArgsConfig
+from .tool_configs import BaseToolConfig
+from .tool_configs import ToolArgsConfig
 from .tool_context import ToolContext
 
 if TYPE_CHECKING:

src/google/adk/tools/base_tool.py

@@ -249,106 +249,3 @@ def _find_tool_with_function_declarations(
       ),
       None,
   )
-
-
-class ToolArgsConfig(BaseModel):
-  """The configuration for tool arguments.
-
-  This config allows arbitrary key-value pairs as tool arguments.
-  """
-
-  model_config = ConfigDict(extra="allow")
-
-
-class ToolConfig(BaseModel):
-  """The configuration for a tool.
-
-  The config supports these types of tools:
-  1. ADK built-in tools
-  2. User-defined tool instances
-  3. User-defined tool classes
-  4. User-defined functions that generate tool instances
-  5. User-defined function tools
-
-  For examples:
-
-    1. For ADK built-in tool instances or classes in `google.adk.tools` package,
-    they can be referenced directly with the `name` and optionally with
-    `config`.
-
-    ```
-    tools:
-      - name: google_search
-      - name: AgentTool
-        config:
-          agent: ./another_agent.yaml
-          skip_summarization: true
-    ```
-
-    2. For user-defined tool instances, the `name` is the fully qualified path
-    to the tool instance.
-
-    ```
-    tools:
-      - name: my_package.my_module.my_tool
-    ```
-
-    3. For user-defined tool classes (custom tools), the `name` is the fully
-    qualified path to the tool class and `config` is the arguments for the tool.
-
-    ```
-    tools:
-      - name: my_package.my_module.my_tool_class
-        config:
-          my_tool_arg1: value1
-          my_tool_arg2: value2
-    ```
-
-    4. For user-defined functions that generate tool instances, the `name` is
-    the fully qualified path to the function and `config` is passed to the
-    function as arguments.
-
-    ```
-    tools:
-      - name: my_package.my_module.my_tool_function
-        config:
-          my_function_arg1: value1
-          my_function_arg2: value2
-    ```
-
-    The function must have the following signature:
-    ```
-    def my_function(config: ToolArgsConfig) -> BaseTool:
-      ...
-    ```
-
-    5. For user-defined function tools, the `name` is the fully qualified path
-    to the function.
-
-    ```
-    tools:
-      - name: my_package.my_module.my_function_tool
-    ```
-  """
-
-  model_config = ConfigDict(extra="forbid")
-
-  name: str
-  """The name of the tool.
-
-  For ADK built-in tools, the name is the name of the tool, e.g. `google_search`
-  or `AgentTool`.
-
-  For user-defined tools, the name is the fully qualified path to the tool, e.g.
-  `my_package.my_module.my_tool`.
-  """
-
-  args: Optional[ToolArgsConfig] = None
-  """The args for the tool."""
-
-
-class BaseToolConfig(BaseModel):
-  """The base configurations for all the tools."""
-
-  model_config = ConfigDict(extra="forbid")
-  """Forbid extra fields."""

src/google/adk/tools/crewai_tool.py

@@ -18,9 +18,9 @@
 from typing_extensions import override
 
 from . import _automatic_function_calling_util
-from .base_tool import BaseToolConfig
-from .base_tool import ToolArgsConfig
 from .function_tool import FunctionTool
+from .tool_configs import BaseToolConfig
+from .tool_configs import ToolArgsConfig
 
 try:
   from crewai.tools import BaseTool as CrewaiBaseTool

src/google/adk/tools/example_tool.py

@@ -24,8 +24,8 @@
 from ..examples.base_example_provider import BaseExampleProvider
 from ..examples.example import Example
 from .base_tool import BaseTool
-from .base_tool import BaseToolConfig
-from .base_tool import ToolArgsConfig
+from .tool_configs import BaseToolConfig
+from .tool_configs import ToolArgsConfig
 from .tool_context import ToolContext
 
 if TYPE_CHECKING:

src/google/adk/tools/langchain_tool.py

@@ -24,9 +24,9 @@
 from typing_extensions import override
 
 from . import _automatic_function_calling_util
-from .base_tool import BaseToolConfig
-from .base_tool import ToolArgsConfig
 from .function_tool import FunctionTool
+from .tool_configs import BaseToolConfig
+from .tool_configs import ToolArgsConfig
 
 
 class LangchainTool(FunctionTool):

src/google/adk/tools/tool_configs.py

@@ -0,0 +1,128 @@
+# 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 Optional
+
+from pydantic import BaseModel
+from pydantic import ConfigDict
+
+from ..utils.feature_decorator import working_in_progress
+
+
+@working_in_progress("BaseToolConfig is not ready for use.")
+class BaseToolConfig(BaseModel):
+  """The base class for all tool configs."""
+
+  model_config = ConfigDict(extra="forbid")
+  """Forbid extra fields."""
+
+
+@working_in_progress("ToolArgsConfig is not ready for use.")
+class ToolArgsConfig(BaseModel):
+  """Config to host free key-value pairs for the args in ToolConfig."""
+
+  model_config = ConfigDict(extra="allow")
+
+
+@working_in_progress("ToolConfig is not ready for use.")
+class ToolConfig(BaseModel):
+  """The configuration for a tool.
+
+  The config supports these types of tools:
+  1. ADK built-in tools
+  2. User-defined tool instances
+  3. User-defined tool classes
+  4. User-defined functions that generate tool instances
+  5. User-defined function tools
+
+  For examples:
+
+    1. For ADK built-in tool instances or classes in `google.adk.tools` package,
+    they can be referenced directly with the `name` and optionally with
+    `args`.
+
+    ```
+    tools:
+      - name: google_search
+      - name: AgentTool
+        args:
+          agent: ./another_agent.yaml
+          skip_summarization: true
+    ```
+
+    2. For user-defined tool instances, the `name` is the fully qualified path
+    to the tool instance.
+
+    ```
+    tools:
+      - name: my_package.my_module.my_tool
+    ```
+
+    3. For user-defined tool classes (custom tools), the `name` is the fully
+    qualified path to the tool class and `args` is the arguments for the tool.
+
+    ```
+    tools:
+      - name: my_package.my_module.my_tool_class
+        args:
+          my_tool_arg1: value1
+          my_tool_arg2: value2
+    ```
+
+    4. For user-defined functions that generate tool instances, the `name` is
+    the fully qualified path to the function and `args` is passed to the
+    function as arguments.
+
+    ```
+    tools:
+      - name: my_package.my_module.my_tool_function
+        args:
+          my_function_arg1: value1
+          my_function_arg2: value2
+    ```
+
+    The function must have the following signature:
+    ```
+    def my_function(args: ToolArgsConfig) -> BaseTool:
+      ...
+    ```
+
+    5. For user-defined function tools, the `name` is the fully qualified path
+    to the function.
+
+    ```
+    tools:
+      - name: my_package.my_module.my_function_tool
+    ```
+
+    If the above use cases don't suffice, users can define a custom tool config
+    by extending BaseToolConfig and override from_config() in the custom tool.
+  """
+
+  model_config = ConfigDict(extra="forbid")
+
+  name: str
+  """The name of the tool.
+
+  For ADK built-in tools, `name` is the name of the tool, e.g. `google_search`
+  or `AgentTool`.
+
+  For user-defined tools, the name is the fully qualified path to the tool, e.g.
+  `my_package.my_module.my_tool`.
+  """
+
+  args: Optional[ToolArgsConfig] = None
+  """The args for the tool."""

tests/unittests/tools/test_tool_config.py

@@ -13,7 +13,7 @@
 # limitations under the License.
 
 from google.adk.tools import VertexAiSearchTool
-from google.adk.tools.base_tool import ToolConfig
+from google.adk.tools.tool_configs import ToolConfig
 from google.genai import types
 import yaml