With the release of ArcGIS Pro 3.0, there are three toolbox formats available in ArcGIS. This matrix is an attempt to help you decide which is appropriate for your work.
| | atbx | tbx | pyt |
| Description | ArcGIS Pro 3.x | ArcMap, Pro 1.x, 2.x | ArcMap 10.x, Pro |
| Format | XML-based | text/binary | python code |
| Model Builder support | Yes | Yes | No (but references to model builder tools supported) |
| Python skills required | Minimal | Minimal | Yes |
| Container (location toolbox is saved) | Folder or gdb | Folder or gdb | Folder |
| Script tool parameter validation | Property sheets and validation code | Property sheets and validation code | code |
| Full read/write support across versions | Pro 3.x only | Within current version (Pro 2.1, ArcMap 10.8) | With careful coding can support all versions (at least in a limited way), even ArcMap and Pro |
| Read toolbox created with previous version | Yes | Yes | Yes |
| Save toolbox to previous version | Yes (Save to tbx file - not gdb, with optional validation tools) | Yes | No |
| Documentation source | Embedded in toolbox | Embedded in toolbox | XML files in same folder as pyt file |
| Efficient with git and other version control systems | No | No | Yes (as pyt and associated .py or .xml files are entirely code) |
| Embedded code encryption supported | Yes | Yes | No |
