feat: add enable_web_search config to disable web search (#681) (#760)

* feat: add enable_web_search config to disable web search (#681)

* fix: skip enforce_researcher_search validation when web search is disabled

- Return json.dumps([]) instead of empty string for consistency in background_investigation_node

- Add enable_web_search check to skip validation warning when user intentionally disabled web search

- Add warning log when researcher has no tools available

- Update tests to include new enable_web_search parameter

* fix: address Copilot review feedback

- Coordinate enforce_web_search with enable_web_search in validate_and_fix_plan

- Fix misleading comment in background_investigation_node

* docs: add warning about local RAG setup when disabling web search

* docs: add web search toggle section to configuration guide

src/server/app.py

@@ -132,6 +132,7 @@ async def chat_stream(request: ChatRequest):
             request.interrupt_feedback,
             request.mcp_settings if mcp_enabled else {},
             request.enable_background_investigation,
+            request.enable_web_search,
             request.report_style,
             request.enable_deep_thinking,
             request.enable_clarification,
@@ -517,6 +518,7 @@ async def _astream_workflow_generator(
     interrupt_feedback: str,
     mcp_settings: dict,
     enable_background_investigation: bool,
+    enable_web_search: bool,
     report_style: ReportStyle,
     enable_deep_thinking: bool,
     enable_clarification: bool,
@@ -594,6 +596,7 @@ async def _astream_workflow_generator(
         "max_step_num": max_step_num,
         "max_search_results": max_search_results,
         "mcp_settings": mcp_settings,
+        "enable_web_search": enable_web_search,
         "report_style": report_style.value,
         "enable_deep_thinking": enable_deep_thinking,
         "interrupt_before_tools": interrupt_before_tools,

src/server/chat_request.py

@@ -62,6 +62,9 @@ class ChatRequest(BaseModel):
     enable_background_investigation: Optional[bool] = Field(
         True, description="Whether to get background investigation before plan"
     )
+    enable_web_search: Optional[bool] = Field(
+        True, description="Whether to enable web search, set to False to use only local RAG"
+    )
     report_style: Optional[ReportStyle] = Field(
         ReportStyle.ACADEMIC, description="The style of the report"
     )