DOC: Clarify available options

Author: mgxd

README.md

@@ -44,8 +44,10 @@ However, as infant brains can vastly differ depending on age, providing the foll
 > - A segmented and labelled NIfTI that includes `Segmentation` in the filename.
 > - A brainmasked T1w NIfTI that includes `T1w` in the filename.
 
+
+##### Extensive Usage
 <details>
-<summary>Extensive argument list</summary>
+<summary>Click to view all options</summary>
 
 ```
 usage: nibabies [-h] [--version] [--skip_bids_validation]
@@ -336,6 +338,8 @@ RUNNING: singularity run --cleanenv -B /path/to/data:/data:ro \
 -B /path/to/output:/out nibabies-0.1.1.sif /data /out participant --age-months 12
 ```
 
+The ``nibabies-wrapper`` accepts all of the [available options for NiBabies](#extensive-usage), automatically translating local files and directories into mount points.
+
 ### Outputs
 
 TODO - Refer to [fMRIPrep's outputs](https://fmriprep.org/en/20.2.1/outputs.html) for now.