diff --git a/src/agent.py b/src/agent.py
index bb53aa90..eafc36b3 100644
--- a/src/agent.py
+++ b/src/agent.py
@@ -26,8 +26,8 @@ logger = logging.getLogger(__name__)
 
 USER_REPRESENTATION_METAMESSAGE_TYPE = "honcho_user_representation"
 
-DEF_DIALECTIC_PROVIDER = ModelProvider.ANTHROPIC
-DEF_DIALECTIC_MODEL = "claude-3-7-sonnet-20250219"
+DEF_DIALECTIC_PROVIDER = ModelProvider.OPENAI # patching to openai for mocking with muk
+DEF_DIALECTIC_MODEL = "gpt-4o" 
 
 DEF_QUERY_GENERATION_PROVIDER = ModelProvider.GROQ
 DEF_QUERY_GENERATION_MODEL = "llama-3.1-8b-instant"
diff --git a/src/deriver/tom/long_term.py b/src/deriver/tom/long_term.py
index a9a7f2c5..ba487458 100644
--- a/src/deriver/tom/long_term.py
+++ b/src/deriver/tom/long_term.py
@@ -13,8 +13,8 @@ from src.utils.model_client import ModelClient, ModelProvider
 logger = logging.getLogger(__name__)
 
 # Constants for fact extraction
-FACT_EXTRACTION_PROVIDER = ModelProvider.GEMINI
-FACT_EXTRACTION_MODEL = "gemini-2.0-flash-lite"
+FACT_EXTRACTION_PROVIDER = ModelProvider.OPENAI # patching to openai for mocking with muk
+FACT_EXTRACTION_MODEL = "gpt-4o"
 
 USER_REPRESENTATION_PROVIDER = ModelProvider.GROQ
 USER_REPRESENTATION_MODEL = "llama-3.3-70b-versatile"
diff --git a/src/utils/history.py b/src/utils/history.py
index 6cec266f..9d90126b 100644
--- a/src/utils/history.py
+++ b/src/utils/history.py
@@ -38,8 +38,8 @@ class SummaryType(Enum):
 
 
 # Default model settings for summary generation
-DEFAULT_PROVIDER = ModelProvider.GEMINI
-DEFAULT_MODEL = "gemini-2.0-flash-lite"
+DEFAULT_PROVIDER = ModelProvider.OPENAI # patching to openai for mocking with muk
+DEFAULT_MODEL = "gpt-4o"
 
 
 async def get_session_summaries(
diff --git a/src/utils/model_client.py b/src/utils/model_client.py
index 8c98a800..f7ed7a88 100644
--- a/src/utils/model_client.py
+++ b/src/utils/model_client.py
@@ -64,7 +64,7 @@ class ModelClient:
 
     def __init__(
         self,
-        provider: ModelProvider = ModelProvider.ANTHROPIC,
+        provider: ModelProvider = ModelProvider.OPENAI, # patching default provider to openai for mocking with muk
         model: Optional[str] = None,
         api_key: Optional[str] = None,
         base_url: Optional[str] = None,