ValueError: Fieldmap-less (SyN) estimation was requested, but PhaseEncodingDirection information appears to be absent. fMRIprep v. 22.0.2

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I went down the rabbit hole: what makes FMRIPREP v22.0.2 not “recognize” the fieldmaps is the fact that in your dataset_description.json , you use:

    "DatasetType": "derivative",
    "GeneratedBy": [
        {
            "Name": "Manual"
        }
    ],

I don’t know what is the meaning of these two fields, and how they are related to the behavior of the fieldmap detection by FMRIPREP v22.0.2, but it is fact. If you remove those fields from dataset_description.json, the SDC correction is run by FMRIPREP v 22.0.2!

This does not affect FMRIPREP v21.0.2 or earlier.