chore: add model-path param flag for convert API for better clarity (#702)

* chore: add model-path param flag for convert API for better clarity

Signed-off-by: Jake Hall <jaycoolslm@gmail.com>

* chore: refactor argparse for multiple string options

Signed-off-by: Jake Hall <jaycoolslm@gmail.com>

* Update mlx_lm/convert.py

* Update README.md

---------

Signed-off-by: Jake Hall <jaycoolslm@gmail.com>
Co-authored-by: Awni Hannun <awni.hannun@gmail.com>

README.md

@@ -170,7 +170,7 @@ mlx_lm.generate --help
 To quantize a model from the command line run:
 
 ```
-mlx_lm.convert --hf-path mistralai/Mistral-7B-Instruct-v0.3 -q
+mlx_lm.convert --model mistralai/Mistral-7B-Instruct-v0.3 -q
 ```
 
 For more options run:
@@ -185,7 +185,7 @@ You can upload new models to Hugging Face by specifying `--upload-repo` to
 
 ```
 mlx_lm.convert \
-    --hf-path mistralai/Mistral-7B-Instruct-v0.3 \
+    --model mistralai/Mistral-7B-Instruct-v0.3 \
     -q \
     --upload-repo mlx-community/my-4bit-mistral
 ```

mlx_lm/convert.py

@@ -179,7 +179,12 @@ def configure_parser() -> argparse.ArgumentParser:
         description="Convert Hugging Face model to MLX format"
     )
 
-    parser.add_argument("--hf-path", type=str, help="Path to the Hugging Face model.")
+    parser.add_argument(
+        "--hf-path",
+        "--model",
+        type=str,
+        help="Path to the model. This can be a local path or a Hugging Face Hub model identifier.",
+    )
     parser.add_argument(
         "--mlx-path", type=str, default="mlx_model", help="Path to save the MLX model."
     )