chore: Adjust the instruction of agent builder assistant for how to use google_search tool and url_context tool

PiperOrigin-RevId: 802629718

contributing/samples/adk_agent_builder_assistant/instruction_embedded.template

@@ -159,8 +159,8 @@ Always reference this schema when creating configurations to ensure compliance.
 ### ADK Knowledge and Research Tools
 
 #### Web-based Research
-- **google_search_agent**: Search web for ADK examples, patterns, and documentation (built-in tool via sub-agent)
-- **url_context_agent**: Fetch and analyze content from URLs - GitHub, docs, examples (built-in tool via sub-agent)
+- **google_search_agent**: Search web for ADK examples, patterns, and documentation (returns full page content as results)
+- **url_context_agent**: Fetch content from specific URLs when mentioned in search results or user queries (use only when specific URLs need additional fetching)
 
 #### Local ADK Source Search
 - **search_adk_source**: Search ADK source code using regex patterns for precise code lookups
@@ -200,15 +200,17 @@ Always reference this schema when creating configurations to ensure compliance.
    * Analyze class relationships and usage patterns
 
 **For External Examples and Documentation:**
-- **google_search_agent**: Search to FIND relevant content and examples
+- **google_search_agent**: Search and analyze web content (returns full page content, not just URLs)
   * Search within key repositories: "site:github.com/google/adk-python ADK SequentialAgent examples"
   * Search documentation: "site:github.com/google/adk-docs agent configuration patterns"
   * Search sample repository: "site:github.com/google/adk-samples multi-agent workflow"
   * General searches: "ADK workflow patterns", "ADK tool integration patterns", "ADK project structure"
-- **url_context_agent**: Fetch and analyze FULL CONTENT of specific URLs identified through search
-  * Use after google_search_agent finds relevant URLs
-  * Fetch specific GitHub files, documentation pages, or examples
-  * Analyze complete implementation details and extract patterns
+  * Returns complete page content as search results - no need for additional URL fetching
+- **url_context_agent**: Fetch specific URLs only when:
+  * Specific URLs are mentioned in search results that need additional content
+  * User provides specific URLs in their query
+  * You need to fetch content from URLs found within google_search results
+  * NOT needed for general searches - google_search_agent already provides page content
 
 **Research for Agent Building:**
 - When user requests complex multi-agent systems: Search for similar patterns in samples

contributing/samples/adk_agent_builder_assistant/instruction_query.template

@@ -159,11 +159,16 @@ You have access to comprehensive tools for:
 3. **query_schema** - Query AgentConfig schema for field definitions
 
 **For External Examples and Documentation:**
-- **google_search_agent**: Search to FIND relevant content and examples
+- **google_search_agent**: Search and analyze web content (returns full page content, not just URLs)
   * Search within key repositories: "site:github.com/google/adk-python ADK SequentialAgent examples"
   * Search documentation: "site:github.com/google/adk-docs agent configuration patterns"
   * General searches: "ADK workflow patterns", "ADK tool integration patterns"
-- **url_context_agent**: Fetch and analyze FULL CONTENT of specific URLs identified through search
+  * Returns complete page content as search results - no need for additional URL fetching
+- **url_context_agent**: Fetch specific URLs only when:
+  * Specific URLs are mentioned in search results that need additional content
+  * User provides specific URLs in their query
+  * You need to fetch content from URLs found within google_search results
+  * NOT needed for general searches - google_search_agent already provides page content
 
 **Research for Agent Building:**
 - When user requests complex multi-agent systems: Search for similar patterns in samples
@@ -175,7 +180,7 @@ You have access to comprehensive tools for:
 
 ### When Creating Python Tools or Callbacks:
 1. **Always search for current examples first**: Use google_search_agent to find "ADK tool_context examples" or "ADK callback_context examples"
-2. **Reference contributing/samples**: Use url_context_agent to fetch specific examples from https://github.com/google/adk-python/tree/main/contributing/samples
+2. **Reference contributing/samples**: Use google_search_agent to find examples, or url_context_agent only if specific URLs are identified that need additional content
 3. **Look for similar patterns**: Search for tools or callbacks that match your use case
 4. **Use snake_case**: Function names should be snake_case (e.g., `check_prime`, `roll_dice`)
 5. **Remove tool suffix**: Don't add "_tool" to function names
@@ -184,12 +189,14 @@ You have access to comprehensive tools for:
 8. **Follow current ADK patterns**: Always search for and reference the latest examples from contributing/samples
 
 ### Research and Examples:
-- Use google_search_agent to find "ADK [use-case] examples" or "ADK [pattern] configuration"
-- Use url_context_agent to fetch examples from:
-  * GitHub repositories: https://github.com/google/adk-samples/
-  * Contributing examples: https://github.com/google/adk-python/tree/main/contributing
-  * Documentation: https://github.com/google/adk-docs
-  * Community examples and patterns
+- Use google_search_agent to find "ADK [use-case] examples" or "ADK [pattern] configuration" (returns full content)
+- Use url_context_agent only when:
+  * Specific URLs are found in search results that need additional content
+  * User provides specific URLs to analyze
+  * You need to fetch specific examples from identified URLs:
+    * GitHub repositories: https://github.com/google/adk-samples/
+    * Contributing examples: https://github.com/google/adk-python/tree/main/contributing
+    * Documentation: https://github.com/google/adk-docs
 - Adapt existing patterns to user requirements while maintaining compliance
 
 ## Important ADK Requirements