backend/app/core/ai_chat_service.py

@@ -465,7 +465,9 @@ async def send_message(
         for msg in history
     ]
 
-    provider = get_ai_provider()
+    # Resolve model for this action type
+    action_model = settings.get_model_for_action(action_type)
+    provider = get_ai_provider(model=action_model)
     response_text, input_tokens, output_tokens = await provider.generate_text(
         system_prompt=system_prompt,
         messages=provider_messages,
@@ -584,7 +586,7 @@ Also provide metadata as a separate JSON object after the tree:
 
     provider_messages.append({"role": "user", "content": generation_instruction})
 
-    provider = get_ai_provider()
+    provider = get_ai_provider(model=settings.get_model_for_action("generate_full"))
 
     for attempt in range(2):  # One try + one retry
         response_text, input_tokens, output_tokens = await provider.generate_text(

backend/app/core/ai_provider.py

@@ -209,9 +209,13 @@ class AnthropicProvider(AIProvider):
         return await self.generate_json(system_prompt, messages, max_tokens)
 
 
-def get_ai_provider() -> AIProvider:
+def get_ai_provider(model: str | None = None) -> AIProvider:
     """Factory that returns the configured AI provider.
 
+    Args:
+        model: Optional model override (Anthropic model ID). Only applied to
+               AnthropicProvider; Gemini always uses settings.AI_MODEL_GEMINI.
+
     Selection logic:
     1. If AI_PROVIDER == "gemini" and GOOGLE_AI_API_KEY is set -> GeminiProvider
     2. If AI_PROVIDER == "anthropic" and ANTHROPIC_API_KEY is set -> AnthropicProvider
@@ -230,7 +234,7 @@ def get_ai_provider() -> AIProvider:
         if settings.ANTHROPIC_API_KEY:
             return AnthropicProvider(
                 api_key=settings.ANTHROPIC_API_KEY,
-                model=settings.AI_MODEL_ANTHROPIC,
+                model=model or settings.AI_MODEL_ANTHROPIC,
                 timeout=settings.AI_REQUEST_TIMEOUT_SECONDS,
             )
 
@@ -238,7 +242,7 @@ def get_ai_provider() -> AIProvider:
         if settings.ANTHROPIC_API_KEY:
             return AnthropicProvider(
                 api_key=settings.ANTHROPIC_API_KEY,
-                model=settings.AI_MODEL_ANTHROPIC,
+                model=model or settings.AI_MODEL_ANTHROPIC,
                 timeout=settings.AI_REQUEST_TIMEOUT_SECONDS,
             )
         # Fallback to Gemini