drupal-field-system

Drupal Field System

This skill covers managing fields for a Drupal site. It applies to all fieldable entity types (node, taxonomy_term, media, block_content, user, paragraph, etc.).

Capabilities

Discovery

• List all fieldable entity types and their bundles
• List all available field types with their default widgets and formatters
• List available widgets for a specific field type
• List available formatters for a specific field type
• List available view modes and form modes for an entity type

Field CRUD

• List all configurable fields on any entity type bundle
• Get full details of a field including storage and field settings
• Add fields to any fieldable entity type bundle with full settings support
• Update field properties (label, required, description, field settings)
• Remove fields from entity type bundles

Custom Field Support

• Add Custom Fields (from the custom_field module) with structured column definitions
• Each column defines a sub-field with type and configuration

Form Display (Widgets)

• Get form display configuration showing all widget assignments
• Update form display: change widget type, weight, widget settings, or hide fields

View Display (Formatters)

• Get view display configuration showing all formatter assignments
• Update view display: change formatter type, label position, weight, formatter settings, or hide fields

Available Operations

#	Operation	Description
1	List Fieldable Entity Types	List all entity types that support fields and their bundles
2	List Field Types	List all available field types with default widgets and formatters
3	List Available Widgets	List compatible widgets for a specific field type
4	List Available Formatters	List compatible formatters for a specific field type
5	List Fields	List all configurable fields on an entity type bundle
6	Get Field	Get full details of a specific field (storage settings, field settings)
7	Add Field	Create a new field on an entity type bundle with full settings support
8	Get Entity Reference Handlers	Discover available entity reference target types and bundles
9	Update Field	Update field properties such as label, required, description, or settings
10	Remove Field	Remove a field from an entity type bundle
11	Add Custom Field	Add a custom field with structured column definitions (requires custom_field module)
12	Get Form Display	Get form display configuration showing all widget assignments
13	Update Form Display	Change widget type, weight, widget settings, or hide fields on a form display
14	Get View Display	Get view display configuration showing all formatter assignments
15	Update View Display	Change formatter type, label position, weight, formatter settings, or hide fields on a view display
16	List View Modes	List available view modes for an entity type
17	List Form Modes	List available form modes for an entity type

Workflow

1. Start by discovering available entity types with List Fieldable Entity Types.
2. Use List Field Types to find the right field type.
3. Use List Available Widgets / List Available Formatters to find compatible display plugins.
4. Create fields with Add Field, providing storage_settings and field_settings as JSON strings.
5. Configure form display with Update Form Display.
6. Configure view display with Update View Display.

Complex Field Settings Examples

Entity Reference (IMPORTANT -- requires BOTH storage_settings and field_settings)

For entity_reference fields, provide the correct configuration in BOTH settings.

Reference to node bundles:

storage_settings: {"target_type": "node"}
field_settings: {"handler": "default:node", "handler_settings": {"target_bundles": {"article": "article"}}}

Reference to taxonomy terms:

storage_settings: {"target_type": "taxonomy_term"}
field_settings: {"handler": "default:taxonomy_term", "handler_settings": {"target_bundles": {"tags": "tags"}, "auto_create": true}}

Reference to users (no bundles needed):

storage_settings: {"target_type": "user"}
field_settings: {"handler": "default:user"}

Reference to media:

storage_settings: {"target_type": "media"}
field_settings: {"handler": "default:media", "handler_settings": {"target_bundles": {"image": "image"}}}

Key rules for entity_reference:

• storage_settings MUST contain target_type (the entity type being referenced)
• field_settings MUST contain handler in format default:{target_type}
• handler_settings.target_bundles is a map where keys AND values are the bundle machine name
• If target_bundles is omitted or empty, ALL bundles of that type are referenceable
• For taxonomy, add "auto_create": true in handler_settings to allow creating new terms inline
• Use Get Entity Reference Handlers to discover available target types and bundles
• If field_settings includes a handler but storage_settings is omitted, the tool will auto-detect target_type from the handler string

List String

storage_settings: {"allowed_values": {"red": "Red", "blue": "Blue"}}

Address (with available_countries)

field_settings: {"available_countries": ["US", "CA", "GB"]}

Custom Field (columns)

columns: [{"name": "title", "type": "string", "length": 255}, {"name": "count", "type": "integer", "unsigned": true}]

Important Notes

• Always use entity_type + bundle to identify where fields live.
• Field names should typically start with field_.
• Use cardinality -1 for unlimited values, 1 for single value.
• JSON strings must be valid JSON for storage_settings, field_settings, and widget/formatter settings.
• For entity_reference fields, ALWAYS use Get Entity Reference Handlers first to discover correct target types and bundles.
• The Custom Field tool requires the custom_field module to be installed.

Example Workflows

Discovery

• "List all fieldable entity types on this site"
• "What field types are available?"
• "What widgets can I use for an entity_reference field?"
• "What formatters are available for image fields?"
• "What view modes does the node entity type have?"

Field CRUD

• "List all fields on the article content type"
• "Show me the details of the field_tags field on articles"
• "Add a text_long field called field_summary with label 'Summary' to the article content type"
• "Add an entity_reference field called field_related_articles to articles that references other articles"
• "Add a list_string field called field_status to articles with allowed values: draft, review, published"
• "Make the field_summary field required on articles"
• "Update the description of field_tags on articles to 'Select relevant tags'"
• "Remove the field_subtitle field from articles"

Cross-Entity Type Operations

• "Add a string field called field_subtitle to the tags taxonomy vocabulary"
• "List all fields on the user entity type"
• "Add an image field to the basic block content type"

Custom Fields

• "Add a custom field called field_dimensions to articles with columns: width (integer), height (integer), unit (string)"

Form Display

• "Show me the form display for articles"
• "Change the widget for field_body on articles to text_textarea_with_summary"
• "Set the weight of field_tags on articles to 10"
• "Hide the field_subtitle field from the article form"
• "Set the widget settings for field_body with rows: 15"

View Display

• "Show me the view display for articles"
• "Change the formatter for field_image on articles to image with image_style: large"
• "Set the label position for field_tags on articles to inline"
• "Hide the field_subtitle from the article teaser view mode"
• "Set the weight of field_body on articles to 5 in the default view display"

Complex Workflows

• "Create a complete product content type with fields for price (decimal), SKU (string), description (text_long), and category (entity_reference to taxonomy). Configure the form display with appropriate widgets and the view display with formatters."