SIDECAR_KEY_REQUIRED not documented

[jens-k]

I ran the BIDS validator on a super simple dataset (one subject, one session, just for testing) and got the error "SIDECAR_KEY_REQUIRED (SoftwareFilters)".

I cannot find any information about this issue. The validator provides a link but (as for any error or warning I have ever encountered), the content behind the link seems unrelated to my issue or too cryptic to make sense of it.

I therefore tried to look for "SIDECAR_KEY_REQUIRED" and "SIDECAR_KEY" (which is the type of error, so it should be way more common than the particular one I got about software filters) on the following websites:

• BIDS specification (https://bids-specification.readthedocs.io/)
• BIDS Manual (https://bids-standard.github.io/)

I have no hits for any of the terms. As this seems to be an entirely undocumented requirement/tag/error, I thought this might be considered a bug. I found a cryptic description of "SoftwareFilters" here: https://bids-specification.readthedocs.io/en/stable/glossary.html#softwarefilters-metadata but a normal user cannot be expected to understand this schema, and it does not fit to how I solved the problem.

The answer the user should get is:
In the sidecar file "*****.json", we would have expected a key called "SoftwareFilters". This key is specific for the eeg datatype. You can fix the issue by adding another line
"SoftwareFilters": "anystringiguess",
to the json file.

Is there an effort to fix these error messages? If so, I'd be glad to contribute.

[github-actions]

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This is an automated reply, generated by FAQtory

[Remi-Gau]

Hey @jens-k

Thanks for the report.

This metadata is also mentioned in the tables for the required metadata for EEG, ieeg and MEG.

https://bids-specification.readthedocs.io/en/stable/modality-specific-files/electroencephalography.html#sidecar-json-_eegjson

Though I admit those hits were at the bottom of the search when putting SoftwareFilters in the search bar of the bids specification.

For the improvement of the error message I think you should probably reopen this issue in the repo of the bids validator.

[Remi-Gau]

Will transfer the issue to the BIDS validator repo.