diff --git a/llms/mlx_lm/utils.py b/llms/mlx_lm/utils.py
index c3e0b191..ba22764c 100644
--- a/llms/mlx_lm/utils.py
+++ b/llms/mlx_lm/utils.py
@@ -502,7 +502,7 @@ def save_weights(
         shard_name = shard_file_format.format(i + 1, shards_count)
         shard_path = save_path / shard_name
 
-        mx.save_safetensors(str(shard_path), shard)
+        mx.save_safetensors(str(shard_path), shard, metadata={"format": "mlx"})
 
         for weight_name in shard.keys():
             index_data["weight_map"][weight_name] = shard_name