chore: Correct the callback signatures

PiperOrigin-RevId: 818781277

Author: seanzhougoogle

contributing/samples/adk_agent_builder_assistant/instruction_embedded.template

@@ -288,11 +288,11 @@ from typing import Optional
 from google.genai import types
 from google.adk.agents.callback_context import CallbackContext
 
-def content_filter_callback(context: CallbackContext) -> Optional[types.Content]:
+def content_filter_callback(callback_context: CallbackContext) -> Optional[types.Content]:
     """After agent callback to filter sensitive content."""
-    # Access the response content through context
-    if hasattr(context, 'response') and context.response:
-        response_text = str(context.response)
+    # Access the response content through callback_context
+    if hasattr(callback_context, 'response') and callback_context.response:
+        response_text = str(callback_context.response)
         if "confidential" in response_text.lower():
             filtered_text = response_text.replace("confidential", "[FILTERED]")
             return types.Content(parts=[types.Part(text=filtered_text)])
@@ -308,12 +308,12 @@ from google.adk.models.llm_request import LlmRequest
 from google.adk.models.llm_response import LlmResponse
 from google.adk.agents.callback_context import CallbackContext
 
-def log_model_request(context: CallbackContext, request: LlmRequest) -> Optional[LlmResponse]:
+def log_model_request(callback_context: CallbackContext, request: LlmRequest) -> Optional[LlmResponse]:
     """Before model callback to log requests."""
     print(f"Model request: {{request.contents}}")
     return None  # Return None to proceed with original request
 
-def modify_model_response(context: CallbackContext, response: LlmResponse) -> Optional[LlmResponse]:
+def modify_model_response(callback_context: CallbackContext, response: LlmResponse) -> Optional[LlmResponse]:
     """After model callback to modify response."""
     # Modify response if needed
     return response  # Return modified response or None for original
@@ -327,25 +327,25 @@ from typing import Any, Dict, Optional
 from google.adk.tools.base_tool import BaseTool
 from google.adk.tools.tool_context import ToolContext
 
-def validate_tool_input(tool: BaseTool, args: Dict[str, Any], context: ToolContext) -> Optional[Dict]:
+def validate_tool_input(tool: BaseTool, tool_args: Dict[str, Any], tool_context: ToolContext) -> Optional[Dict]:
     """Before tool callback to validate input."""
     # Validate or modify tool arguments
-    if "unsafe_param" in args:
-        del args["unsafe_param"]
-    return args  # Return modified args or None for original
+    if "unsafe_param" in tool_args:
+        del tool_args["unsafe_param"]
+    return tool_args  # Return modified args or None for original
 
-def log_tool_result(tool: BaseTool, args: Dict[str, Any], context: ToolContext, result: Dict) -> Optional[Dict]:
+def log_tool_result(tool: BaseTool, tool_args: Dict[str, Any], tool_context: ToolContext, result: Dict) -> Optional[Dict]:
     """After tool callback to log results."""
     print(f"Tool {{tool.name}} executed with result: {{result}}")
     return None  # Return None to keep original result
 ```
 
 ## Callback Signature Summary:
-- **Agent Callbacks**: `(CallbackContext) -> Optional[types.Content]`
-- **Before Model**: `(CallbackContext, LlmRequest) -> Optional[LlmResponse]`
-- **After Model**: `(CallbackContext, LlmResponse) -> Optional[LlmResponse]`
-- **Before Tool**: `(BaseTool, Dict[str, Any], ToolContext) -> Optional[Dict]`
-- **After Tool**: `(BaseTool, Dict[str, Any], ToolContext, Dict) -> Optional[Dict]`
+- **Agent Callbacks**: `(callback_context: CallbackContext) -> Optional[types.Content]`
+- **Before Model**: `(callback_context: CallbackContext, request: LlmRequest) -> Optional[LlmResponse]`
+- **After Model**: `(callback_context: CallbackContext, response: LlmResponse) -> Optional[LlmResponse]`
+- **Before Tool**: `(tool: BaseTool, tool_args: Dict[str, Any], tool_context: ToolContext) -> Optional[Dict]`
+- **After Tool**: `(tool: BaseTool, tool_args: Dict[str, Any], tool_context: ToolContext, result: Dict) -> Optional[Dict]`
 
 ## Important ADK Requirements