Fields: Core Structure

A field collects one value, or a list of values. In YAML its type names its field type. The type-specific keys differ, but every field shares the same frame: the core keys each artifact carries, plus a configuration block when the field sits inside a parent.

Field Configuration

As with elements, a field inside a template or element carries a configuration block. These settings depend on where the field sits rather than on the field itself. They govern whether it is required or recommended, how it binds to a property, how it is labelled and laid out, and whether it repeats.

- key: study-name
  type: text-field
  name: Study Name
  configuration:
    required: true

Key	Value	Presence	Meaning
required	boolean	optional	A value must be supplied. Default false.
recommended	boolean	optional	A value is recommended but not required.
hidden	boolean	optional	The field is hidden in the form.
multiple	boolean	optional	The field accepts a list of values.
minItems	integer	optional	Minimum number of values when multiple.
maxItems	integer	optional	Maximum number of values when multiple.
propertyIri	IRI	optional	The property the field binds to in an instance.
overrideLabel	string	optional	A display label for this field in this parent, replacing its name.
overrideDescription	string	optional	A display description for this field in this parent.
continuePreviousLine	boolean	optional	Lay the field out on the same line as the previous one.
valueRecommendation	boolean	optional	Enable value recommendation for the field.
width	integer	optional	Display width, for static fields.
height	integer	optional	Display height, for static fields.

Nested and standalone fields

A field written as a child of a template or element carries its parent-relative settings in configuration. A field written as a top-level definition has no parent, so the field-level settings that do not depend on a parent — hidden, continuePreviousLine, valueRecommendation, and the static-field width and height — appear directly among the field's keys instead. The parent-only settings (propertyIri, overrideLabel, overrideDescription, and the required/recommended/multiple bindings) do not apply to a standalone field.

Semantic labels

Any field may carry semantic labels, independent of its type:

Key	Value	Presence	Meaning
prefLabel	string	optional	A preferred label for the field's meaning.
altLabels	sequence of strings	optional	Alternate labels.

Single and multiple values

By default a field collects one value. Marking it multiple makes it collect a list, with minItems and maxItems bounding the length. Checkbox, multi-select list, and attribute-value fields are inherently multi-valued and do not use multiple; see their entries in Field Types.