Class FieldDefinitionsClient

• Converts the field to newFieldType. The conversion can reset type-specific configuration (length, constraint, format), clear list items when leaving the List type, and clear a default value that cannot be reinterpreted in the new type. Entries already assigned the field may have their values dropped if the existing data cannot survive the new type's domain.
• When the conversion would lose data, allowDataLoss = true is required; otherwise the request is rejected with 400. The server treats the conversion as lossy unless it is one of the explicit safe widenings (Date → DateTime, ShortInteger → LongInteger, ShortInteger → Number, LongInteger → Number) and clearing list items / resetting a constraint / dropping a default would not actually discard data. A field with assigned entries that is not undergoing one of the safe widenings is always treated as lossy.
• Required OAuth scope: repository.Write

• Creates a new metadata field definition with the supplied core attributes, flags, and (optionally) initial list values for list-backed fields.
• Names must be unique within the repository; duplicate-name failures return 400.
• Required OAuth scope: repository.Write

• Deletes the specified field definition. Behavior when the field is referenced by templates or assigned to entries mirrors the underlying repository server response — if rejected by the server, the response surfaces the server error.
• Required OAuth scope: repository.Write

• Useful for impact analysis before performing destructive operations such as type changes or deletion.
• Required OAuth scope: repository.Read

• Lists template definitions that include the specified field. Useful before performing destructive operations on the field.
• Required OAuth scope: repository.Read

• Returns a single field definition associated with the specified ID.
• Useful when a route provides a minimal amount of details and more information about the specific field definition is needed.
• Allowed OData query options: Select
• Required OAuth scope: repository.Read

• Returns the field's configured list-item values in repository-configured order.
• Applies only to list-backed fields; non-list fields return an empty array.
• Required OAuth scope: repository.Read

• Returns the custom-properties bag persisted on the field definition. The bag is an opaque application-defined string → string map scoped to the definition itself (not to a user), useful for attaching integration metadata or application-specific configuration that belongs with the field — for example to encode list-field display preferences such as sort order, or to record an external system's identifier for the field.
• Keys are application-defined; recommend a namespace prefix (e.g. com.acme.workflow.stage, myapp.kind) to avoid collisions across applications.
• The response may include entries written by other applications or by system-managed tooling. Callers should leave unrecognized keys untouched on subsequent UpdateFieldProperties calls — round-tripping them in set preserves them, including them in remove deletes them.
• Required OAuth scope: repository.Read

• Returns a paged listing of field definitions available in the specified repository.
• Useful when trying to find a list of all field definitions available, rather than only those assigned to a specific entry/template.
• Default page size: 100. Allowed OData query options: Select | Count | OrderBy | Skip | Top | SkipToken | Prefer.
• Required OAuth scope: repository.Read

It will continue to make the same call to get a list of field definitions of a fixed size (i.e. maxpagesize) until it reaches the last page (i.e. when next link is null/undefined) or whenever the callback function returns false.

• Related: listFieldDefinitions

Returns a paged listing of field definitions available in the specified repository using a next link

• Related: listFieldDefinitions

• Combines the values of the source fields into a new field. onConflict controls per-entry value conflicts: Fail (default) aborts on conflict, MakeMultivalue keeps all values, UseFirstField keeps the first and discards the rest.
• UseFirstField is lossy and requires allowDataLoss = true; otherwise the request is rejected with 400.
• removeFromTemplates (default false) also removes the source fields from any templates that contain them. The source field definitions themselves are preserved regardless — the merge creates a new field, it does not delete the originals. Callers that want the sources gone must call DeleteFieldDefinition on each after the merge succeeds.
• autoRename (default false) asks the repository to auto-select a non-conflicting name on collision; whether the repository honors this for merges is version-dependent, so callers should pre-validate newFieldName and treat an "already exists" error as a genuine collision.
• At least two source fields are required.
• Required OAuth scope: repository.Write

• Replaces the field's full list-item set wholesale. No partial add/remove endpoints are exposed.
• Duplicates and empty-string values are rejected with 400.
• Required OAuth scope: repository.Write

• Partial-update merge semantics. null = leave unchanged; "" = clear a string property.
• FieldType cannot be changed via this endpoint — use the dedicated ChangeFieldType endpoint.
• ListValues cannot be changed via this endpoint — use the dedicated ListValues endpoints.
• Required OAuth scope: repository.Write

• Entries in set are written (creating or overwriting). Entries in remove are deleted. Properties not mentioned in either are left unchanged.
• Empty set and empty remove is a no-op and returns the current bag.
• Returns the full custom-properties bag after the change.
• The bag is application-defined; the API does not validate key semantics. Recommend namespaced keys (e.g. com.acme.invoice.region, myapp.kind) to avoid collisions.
• Required OAuth scope: repository.Write