Use the description on a Feature to write down exactly what you observe in the ground, before you decide what it means. This is the place for objective detail: the outline of a PIT, the burned soil and charcoal of a HEARTH, the stone courses of a WALL, the dimensions and fill of a POSTHOLE. Good descriptions note color, texture, inclusions, and how sharply the feature's edges are defined. Keeping observation here, separate from the interpretation field, follows sound recording practice — another archaeologist can read your description and reach their own conclusions even if they disagree with your interpretation. The field is optional but is almost always worth filling in.
Technical section
Data model, API, and internals — visible to developers.