diff --git a/llama_toolchain/inference/meta_reference/config.py b/llama_toolchain/inference/meta_reference/config.py
index 6757b1cfa..d9aef32e6 100644
--- a/llama_toolchain/inference/meta_reference/config.py
+++ b/llama_toolchain/inference/meta_reference/config.py
@@ -11,14 +11,17 @@ from llama_models.datatypes import ModelFamily
 from llama_models.schema_utils import json_schema_type
 from llama_models.sku_list import all_registered_models
 
-from pydantic import BaseModel, validator
-
 from llama_toolchain.inference.api import QuantizationConfig
 
+from pydantic import BaseModel, Field, validator
+
 
 @json_schema_type
 class MetaReferenceImplConfig(BaseModel):
-    model: str
+    model: str = Field(
+        default="Meta-Llama3.1-8B-Instruct",
+        description="Model descriptor from `llama model list`",
+    )
     quantization: Optional[QuantizationConfig] = None
     torch_seed: Optional[int] = None
     max_seq_len: int