fix: address reviewer feedback - improve conditional imports and remove provider alias logic\n\n- Improve conditional import approach with better documentation\n- Remove provider-specific alias logic from sku_list.py\n- Conditional imports are necessary because llama4 requires torch\n- Addresses @ashwinb and @raghotham feedback while maintaining compatibility

llama_stack/models/llama/sku_list.py

@@ -23,19 +23,6 @@ def resolve_model(descriptor: str) -> Model | None:
         if descriptor in (m.descriptor(), m.huggingface_repo):
             return m
 
-    # Check provider aliases by attempting to import and check common providers
-    try:
-        from llama_stack.providers.remote.inference.together.models import MODEL_ENTRIES as TOGETHER_ENTRIES
-
-        for entry in TOGETHER_ENTRIES:
-            if descriptor in entry.aliases and entry.llama_model:
-                # Find the model by its descriptor
-                for m in all_registered_models():
-                    if m.descriptor() == entry.llama_model:
-                        return m
-    except ImportError:
-        pass
-
     return None
 
 

llama_stack/providers/utils/inference/prompt_adapter.py

@@ -52,7 +52,7 @@ from llama_stack.models.llama.llama3.prompt_templates import (
 )
 from llama_stack.models.llama.llama3.tokenizer import Tokenizer
 
-# Conditional imports to avoid heavy dependencies during module loading
+# Import llama4 components - these require torch to be available
 try:
     from llama_models.llama4.chat_format import ChatFormat as Llama4ChatFormat
     from llama_models.llama4.prompt_templates.system_prompts import (
@@ -62,8 +62,11 @@ try:
 
     LLAMA4_AVAILABLE = True
 except ImportError:
-    # Llama4 dependencies not available (e.g., torch not installed)
+    # Llama4 requires torch - if not available, we can't use Llama4 features
     LLAMA4_AVAILABLE = False
+    Llama4ChatFormat = None
+    PythonListCustomToolGeneratorLlama4 = None
+    Llama4Tokenizer = None
 from llama_stack.models.llama.sku_list import resolve_model
 from llama_stack.models.llama.sku_types import ModelFamily, is_multimodal
 from llama_stack.providers.utils.inference import supported_inference_models