To use a keep function, prefix it with keep., for example, use keep.len and not len

  - type: threshold
    # Use the len of the results instead of the results
    value: "keep.len({{ steps.db-no-space.results }})"
    compare_to: 10

How to create a new function?

Keep functions are designed to be easily extendible!
To create a new function, all you have to do is to add it to the functions directory file.