feat: integrate Google Gemini LLM provider

backend/.env.example

@@ -7,8 +7,9 @@ SUPABASE_KEY=your_service_role_key
 # These apply to all agent nodes unless overridden below.
 GROQ_API_KEY=your_groq_api_key
 OPENROUTER_API_KEY=your_openrouter_api_key
-LLM_PROVIDER=groq            # "groq" or "openrouter"
-LLM_MODEL=llama-3.3-70b-versatile
+GEMINI_API_KEY=your_gemini_api_key
+LLM_PROVIDER=gemini          # "groq", "openrouter", or "gemini"
+LLM_MODEL=gemini-2.5-pro
 
 # Per-node LLM Overrides (optional)
 # Uncomment to override a specific agent's provider/model.

backend/app/config.py

@@ -29,17 +29,18 @@ class Settings(BaseSettings):
     # LLM Provider Configuration — Global Defaults
     groq_api_key: str = ""
     openrouter_api_key: str = ""
-    llm_provider: Literal["groq", "openrouter"] = "groq"
+    gemini_api_key: str = ""
+    llm_provider: Literal["groq", "openrouter", "gemini"] = "groq"
     llm_model: str = "llama-3.3-70b-versatile"
 
     # Per-node LLM overrides (None = use global defaults above)
-    planner_llm_provider: Optional[Literal["groq", "openrouter"]] = None
+    planner_llm_provider: Optional[Literal["groq", "openrouter", "gemini"]] = None
     planner_llm_model: Optional[str] = None
-    scripter_llm_provider: Optional[Literal["groq", "openrouter"]] = None
+    scripter_llm_provider: Optional[Literal["groq", "openrouter", "gemini"]] = None
     scripter_llm_model: Optional[str] = None
-    coder_llm_provider: Optional[Literal["groq", "openrouter"]] = None
+    coder_llm_provider: Optional[Literal["groq", "openrouter", "gemini"]] = None
     coder_llm_model: Optional[str] = None
-    reflector_llm_provider: Optional[Literal["groq", "openrouter"]] = None
+    reflector_llm_provider: Optional[Literal["groq", "openrouter", "gemini"]] = None
     reflector_llm_model: Optional[str] = None
 
     # Storage Configuration
@@ -59,6 +60,8 @@ def is_llm_configured(self) -> bool:
         """Check if at least one LLM provider is configured."""
         if self.llm_provider == "groq":
             return bool(self.groq_api_key)
+        if self.llm_provider == "gemini":
+            return bool(self.gemini_api_key)
         return bool(self.openrouter_api_key)
 
 

backend/app/services/llm_factory.py

@@ -62,10 +62,14 @@ def create_llm(role: AgentRole, temperature: float = 0.7) -> BaseChatModel:
         return _create_openrouter_llm(
             model, temperature, settings.openrouter_api_key
         )
+    elif provider == "gemini":
+        return _create_gemini_llm(
+            model, temperature, settings.gemini_api_key
+        )
     else:
         raise ValueError(
             f"Unsupported LLM provider '{provider}' for role '{role}'. "
-            f"Supported: groq, openrouter"
+            f"Supported: groq, openrouter, gemini"
         )
 
 
@@ -105,3 +109,22 @@ def _create_openrouter_llm(
         temperature=temperature,
         api_key=api_key,
     )
+
+
+def _create_gemini_llm(
+    model: str, temperature: float, api_key: str
+) -> BaseChatModel:
+    """Create a ChatGoogleGenerativeAI instance."""
+    if not api_key:
+        raise ValueError(
+            "GEMINI_API_KEY is required when using the 'gemini' "
+            "provider. Set it in your .env file."
+        )
+
+    from langchain_google_genai import ChatGoogleGenerativeAI
+
+    return ChatGoogleGenerativeAI(
+        model=model,
+        temperature=temperature,
+        google_api_key=api_key,
+    )

backend/requirements.txt

@@ -28,3 +28,4 @@ httpx>=0.26.0
 # Testing
 pytest>=7.4.0
 pytest-asyncio>=0.21.0
+langchain-google-genai>=1.0.0