diff --git a/config/config.yaml b/config/config.yaml
index a9c764c561..6a1fd597fb 100644
--- a/config/config.yaml
+++ b/config/config.yaml
@@ -117,4 +117,6 @@ RPM: 10
 ### repair operation on the content extracted from LLM's raw output. Warning, it improves the result but not fix all cases.
 # REPAIR_LLM_OUTPUT: false
 
-# PROMPT_FORMAT: json #json or markdown
\ No newline at end of file
+# PROMPT_FORMAT: json #json or markdown
+
+# DISABLE_LLM_PROVIDER_CHECK: false
diff --git a/metagpt/actions/research.py b/metagpt/actions/research.py
index 074cdee0ae..c47a77bdd9 100644
--- a/metagpt/actions/research.py
+++ b/metagpt/actions/research.py
@@ -180,9 +180,11 @@ class WebBrowseAndSummarize(Action):
     llm: BaseGPTAPI = Field(default_factory=LLM)
     desc: str = "Explore the web and provide summaries of articles and webpages."
     browse_func: Union[Callable[[list[str]], None], None] = None
-    web_browser_engine: WebBrowserEngine = WebBrowserEngine(
-        engine=WebBrowserEngineType.CUSTOM if browse_func else None,
-        run_func=browse_func,
+    web_browser_engine: WebBrowserEngine = Field(
+        default_factory=lambda: WebBrowserEngine(
+            engine=WebBrowserEngineType.CUSTOM if WebBrowseAndSummarize.browse_func else None,
+            run_func=WebBrowseAndSummarize.browse_func,
+        )
     )
 
     def __init__(self, **kwargs):
diff --git a/metagpt/config.py b/metagpt/config.py
index 208b4fd7b8..16df19a4cb 100644
--- a/metagpt/config.py
+++ b/metagpt/config.py
@@ -107,7 +107,9 @@ def _update(self):
         self.gemini_api_key = self._get("GEMINI_API_KEY")
         self.ollama_api_base = self._get("OLLAMA_API_BASE")
         self.ollama_api_model = self._get("OLLAMA_API_MODEL")
-        _ = self.get_default_llm_provider_enum()
+
+        if not self._get("DISABLE_LLM_PROVIDER_CHECK"):
+            _ = self.get_default_llm_provider_enum()
 
         self.openai_base_url = self._get("OPENAI_BASE_URL")
         self.openai_proxy = self._get("OPENAI_PROXY") or self.global_proxy
diff --git a/metagpt/llm.py b/metagpt/llm.py
index 8763642f0a..f1cb98daef 100644
--- a/metagpt/llm.py
+++ b/metagpt/llm.py
@@ -6,6 +6,8 @@
 @File    : llm.py
 """
 
+from typing import Optional
+
 from metagpt.config import CONFIG, LLMProviderEnum
 from metagpt.provider.base_gpt_api import BaseGPTAPI
 from metagpt.provider.human_provider import HumanProvider
@@ -14,6 +16,9 @@
 _ = HumanProvider()  # Avoid pre-commit error
 
 
-def LLM(provider: LLMProviderEnum = CONFIG.get_default_llm_provider_enum()) -> BaseGPTAPI:
+def LLM(provider: Optional[LLMProviderEnum] = None) -> BaseGPTAPI:
     """get the default llm provider"""
+    if provider is None:
+        provider = CONFIG.get_default_llm_provider_enum()
+
     return LLM_REGISTRY.get_provider(provider)
diff --git a/metagpt/logs.py b/metagpt/logs.py
index ab1bc4e94b..fb0fdd5536 100644
--- a/metagpt/logs.py
+++ b/metagpt/logs.py
@@ -8,6 +8,7 @@
 
 import sys
 from datetime import datetime
+from functools import partial
 
 from loguru import logger as _logger
 
@@ -26,3 +27,15 @@ def define_log_level(print_level="INFO", logfile_level="DEBUG"):
 
 
 logger = define_log_level()
+
+
+def log_llm_stream(msg):
+    _llm_stream_log(msg)
+
+
+def set_llm_stream_logfunc(func):
+    global _llm_stream_log
+    _llm_stream_log = func
+
+
+_llm_stream_log = partial(print, end="")
diff --git a/metagpt/provider/google_gemini_api.py b/metagpt/provider/google_gemini_api.py
index 682f7b5072..825b0bfe3c 100644
--- a/metagpt/provider/google_gemini_api.py
+++ b/metagpt/provider/google_gemini_api.py
@@ -20,7 +20,7 @@
 )
 
 from metagpt.config import CONFIG, LLMProviderEnum
-from metagpt.logs import logger
+from metagpt.logs import log_llm_stream, logger
 from metagpt.provider.base_gpt_api import BaseGPTAPI
 from metagpt.provider.llm_provider_registry import register_provider
 from metagpt.provider.openai_api import CostManager, log_and_reraise
@@ -119,7 +119,7 @@ async def _achat_completion_stream(self, messages: list[dict]) -> str:
         collected_content = []
         async for chunk in resp:
             content = chunk.text
-            print(content, end="")
+            log_llm_stream(content)
             collected_content.append(content)
 
         full_content = "".join(collected_content)
diff --git a/metagpt/provider/ollama_api.py b/metagpt/provider/ollama_api.py
index a15c464580..e913f3d0db 100644
--- a/metagpt/provider/ollama_api.py
+++ b/metagpt/provider/ollama_api.py
@@ -15,7 +15,7 @@
 
 from metagpt.config import CONFIG, LLMProviderEnum
 from metagpt.const import LLM_API_TIMEOUT
-from metagpt.logs import logger
+from metagpt.logs import log_llm_stream, logger
 from metagpt.provider.base_gpt_api import BaseGPTAPI
 from metagpt.provider.general_api_requestor import GeneralAPIRequestor
 from metagpt.provider.llm_provider_registry import register_provider
@@ -127,7 +127,7 @@ async def _achat_completion_stream(self, messages: list[dict]) -> str:
             if not chunk.get("done", False):
                 content = self.get_choice_text(chunk)
                 collected_content.append(content)
-                print(content, end="")
+                log_llm_stream(content)
             else:
                 # stream finished
                 usage = self.get_usage(chunk)
diff --git a/metagpt/provider/openai_api.py b/metagpt/provider/openai_api.py
index 8fd8959b2e..0b6fdd869f 100644
--- a/metagpt/provider/openai_api.py
+++ b/metagpt/provider/openai_api.py
@@ -29,7 +29,7 @@
 )
 
 from metagpt.config import CONFIG, Config, LLMProviderEnum
-from metagpt.logs import logger
+from metagpt.logs import log_llm_stream, logger
 from metagpt.provider.base_gpt_api import BaseGPTAPI
 from metagpt.provider.constant import GENERAL_FUNCTION_SCHEMA, GENERAL_TOOL_CHOICE
 from metagpt.provider.llm_provider_registry import register_provider
@@ -222,7 +222,7 @@ async def _achat_completion_stream(self, messages: list[dict]) -> str:
                 chunk_message = chunk.choices[0].delta  # extract the message
                 collected_messages.append(chunk_message)  # save the message
                 if chunk_message.content:
-                    print(chunk_message.content, end="")
+                    log_llm_stream(chunk_message.content)
         print()
 
         full_reply_content = "".join([m.content for m in collected_messages if m.content])
diff --git a/metagpt/provider/zhipuai_api.py b/metagpt/provider/zhipuai_api.py
index 60d9a07773..650720d6f9 100644
--- a/metagpt/provider/zhipuai_api.py
+++ b/metagpt/provider/zhipuai_api.py
@@ -17,7 +17,7 @@
 )
 
 from metagpt.config import CONFIG, LLMProviderEnum
-from metagpt.logs import logger
+from metagpt.logs import log_llm_stream, logger
 from metagpt.provider.base_gpt_api import BaseGPTAPI
 from metagpt.provider.llm_provider_registry import register_provider
 from metagpt.provider.openai_api import CostManager, log_and_reraise
@@ -94,7 +94,7 @@ async def _achat_completion_stream(self, messages: list[dict]) -> str:
             if event.event == ZhiPuEvent.ADD.value:
                 content = event.data
                 collected_content.append(content)
-                print(content, end="")
+                log_llm_stream(content)
             elif event.event == ZhiPuEvent.ERROR.value or event.event == ZhiPuEvent.INTERRUPTED.value:
                 content = event.data
                 logger.error(f"event error: {content}", end="")
diff --git a/metagpt/roles/role.py b/metagpt/roles/role.py
index c25cd947c6..fe61b98781 100644
--- a/metagpt/roles/role.py
+++ b/metagpt/roles/role.py
@@ -152,7 +152,7 @@ class Role(BaseModel):
     builtin_class_name: str = ""
 
     _private_attributes = {
-        "_llm": LLM() if not is_human else HumanProvider(),
+        "_llm": None,
         "_role_id": _role_id,
         "_states": [],
         "_actions": [],