Filling model metadata and saving

After creating the model, is it necessary to save it on the disk so that Processing will be able to load it and register within toolbox.

By default, models are saved in JSON format with the .model extension in the models subdirectory inside the processing directory in the your QGIS user folder. Under Windows, this is usually C:\Users\login\.qgis2 (login here is the name of your Windows user) and under Linux, it is ~/.qgis2. If necessary, you can always change the location of the folder using the Processing settings dialog.

When Processing starts, it looks for files with the .model extension in this directory and loads them. Loaded models appear in the toolbox, in the Models group. Also, they are available in modeler like any other Processing algorithm.

Note

Sometimes, you may get errors if you are loading third-party models. This mainly occurs because some algorithms used in a particular model are not available. For example, a certain algorithm provider is deactivated...