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# List SchemaFieldDefinition items

GET https://{tenant_name}.benchling.com/api/v3/well-plate-schema/{well_plate_schema_id}/field-definitions/items

List SchemaFieldDefinition items.

Reference: https://docs.benchling.com/docs/api/benchling-api/well-plate-schema/fielddefinitions-list

## Authentication

- `Authorization` header (bearer token, required) — Bearer authentication of the form `Bearer <token>`, where token is your auth token.

## Request

### Path parameters

- `well_plate_schema_id` (string, required) — ID of the WellPlateSchema.

### Query parameters

- `archived.anyOf` (boolean, optional) — If true, returns archived items. If false, returns unarchived items. If both true and false, returns archived and unarchived items. Comma-separated list.

### Headers

- `EARLY-ACCESS` (string, optional) — Set to true to access beta operations via /api/v3.

## Response

### 200

OK

- `items` (list of SchemaFieldDefinition, optional)

## Errors

### 400 Well Plate Schema Field Definitions List Request Bad Request Error

Bad Request

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 403 Well Plate Schema Field Definitions List Request Forbidden Error

Forbidden

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 404 Well Plate Schema Field Definitions List Request Not Found Error

Not Found

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 429 Well Plate Schema Field Definitions List Request Too Many Requests Error

Too Many Requests

- `detail` (TooManyRequestsErrorBodyDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)
- `violated-policies` (list of enum, optional) — The budget policies that rejected the request, in canonical order: `user`, `integration`, then `tenant`.
  - Allowed values: `user`, `integration`, `tenant`

### 500 Well Plate Schema Field Definitions List Request Internal Server Error

Internal Server Error

- `detail` (InternalServerErrorBodyDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `errorId` (string, optional)

## Types

### SchemaFieldDefinition

### GeneralErrorDetail

### TooManyRequestsErrorBodyDetail

### InternalServerErrorBodyDetail

### AaPartLinkFieldDefinition

A schema field definition for linking to AA parts.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent AA part. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (ObjectRef, optional) — Union of AaSequenceSchema, SystemCategory
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### AaSequenceLinkFieldDefinition

A schema field definition for linking to AA sequences.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent AA sequence. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (AaSequenceSchemaRef, optional, nullable)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### AnyEntityLinkFieldDefinition

A schema field definition for linking to any entity type without schema or type constraints.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### AttachmentLinkFieldDefinition

A schema field definition for linking to file attachments.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### BaseFieldDefinition

A basic schema field definition for primitive data types. Used for fields with types like TEXT, INTEGER, FLOAT, BOOLEAN, DATE, DATETIME, JSON, and LONG_TEXT. Each field has a user-facing `name` and a `systemName` for warehouse/API access. Fields can be archived when no longer needed. For fields that link to other objects, use `SchemaLinkFieldDefinition`; for dropdown selections, use `DropdownLinkFieldDefinition`.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional) — Determines whether multiple values are allowed
- `isRequired` (boolean, optional) — Determines whether values must be provided
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.
- `type` (enum, optional)
  - Allowed values: `AA_PART_LINK`, `AA_SEQUENCE_LINK`, `ASSAY_REQUEST_LINK`, `ASSAY_RESULT_LINK`, `ASSAY_RUN_LINK`, `BATCH_LINK`, `BLOB_LINK`, `BOOLEAN`, `CUSTOM_ENTITY_LINK`, `DATE`, `DATETIME`, `DNA_SEQUENCE_LINK`, `ENTITY_LINK`, `ENTRY_LINK`, `FLOAT`, `INTEGER`, `JSON`, `LONG_TEXT`, `MIXTURE_LINK`, `MOLECULE_LINK`, `BASE_MOLECULE_LINK`, `PART_LINK`, `RNA_PART_LINK`, `RNA_SEQUENCE_LINK`, `SAMPLE_LINK`, `DROPDOWN`, `STORAGE_LINK`, `TEXT`, `TRANSCRIPTION_LINK`, `TRANSLATION_LINK`

### BooleanFieldDefinition

A field definition for true/false values. Each field has a user-facing `name` and a `systemName` for warehouse and API access. Stores a single boolean value with no additional type-specific properties.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### CustomEntityLinkFieldDefinition

A schema field definition for linking to custom entities.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent custom entity. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (CustomEntitySchemaRef, optional, nullable)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### DateFieldDefinition

A field definition for date-only values, without a time component. Each field has a user-facing `name` and a `systemName` for warehouse and API access. For values that also capture a time and timezone, see `DateTimeFieldDefinition`.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### DateTimeFieldDefinition

A field definition for date and time values with timezone support. Each field has a user-facing `name` and a `systemName` for warehouse and API access. For date-only values without a time component, see `DateFieldDefinition`.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### DecimalFieldDefinition

A field definition for decimal number values. Supports optional numeric constraints via `numericMin` and `numericMax`, an optional `unit` for associating a measurement unit, and `displayPrecision` to control the number of decimal places shown (0 to 10). For whole number values, see `IntegerFieldDefinition`.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `displayPrecision` (integer, optional, nullable) — The number of decimal places to display. Null means no display rounding. Valid range: 0 to 10.
- `id` (string, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `numericMax` (double, optional, nullable) — The maximum allowed value, inclusive. Null means no upper bound.
- `numericMin` (double, optional, nullable) — The minimum allowed value, inclusive. Null means no lower bound.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.
- `unit` (UnitRef, optional, nullable) — The unit of measurement associated with this field's values. Null means the field is unitless.

### DnaOligoLinkFieldDefinition

A schema field definition for linking to DNA oligos.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent DNA Oligo. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (DnaOligoSchemaRef, optional) — The linked item must be of this schema. This is required because we do not allow linking to a generic DNA Oligo.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### DnaPartLinkFieldDefinition

A schema field definition for linking to DNA parts.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent DNA sequence. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (ObjectRef, optional) — Union of DnaSequenceSchema, SystemCategory
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### DnaSequenceLinkFieldDefinition

A schema field definition for linking to DNA sequences.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent DNA sequence. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (DnaSequenceSchemaRef, optional, nullable)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### DropdownLinkFieldDefinition

A schema field definition that links to a dropdown for value selection.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (DropdownRef, optional)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### EntryLinkFieldDefinition

A schema field definition for linking to notebook entries.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### EquipmentLinkFieldDefinition

A schema field definition for linking to equipment.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent Equipment. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (EquipmentSchemaRef, optional, nullable)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### FieldsetLinkFieldDefinition

A schema field definition for linking to entities that implement a fieldset (custom schema interface).

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent entity. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (FieldsetRef, optional)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### IntegerFieldDefinition

A field definition for whole number values. Supports optional numeric constraints via `numericMin` and `numericMax`, and an optional `unit` for associating a measurement unit. For decimal values with display precision control, see `DecimalFieldDefinition`.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `numericMax` (double, optional, nullable) — The maximum allowed value, inclusive. Null means no upper bound.
- `numericMin` (double, optional, nullable) — The minimum allowed value, inclusive. Null means no lower bound.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.
- `unit` (UnitRef, optional, nullable) — The unit of measurement associated with this field's values. Null means the field is unitless.

### JsonFieldDefinition

A field definition for storing structured JSON data. Each field has a user-facing `name` and a `systemName` for warehouse and API access. Stores an arbitrary JSON value rather than a single scalar; for plain text, see `TextFieldDefinition` or `LongTextFieldDefinition`.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### LongTextFieldDefinition

A field definition for multi-line text values with no length restrictions. Each field has a user-facing `name` and a `systemName` for warehouse and API access. For short, single-line text, see `TextFieldDefinition`.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### MixtureLinkFieldDefinition

A schema field definition for linking to mixtures.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent mixture. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (MixtureSchemaRef, optional, nullable)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### MoleculeLinkFieldDefinition

A schema field definition for linking to molecules.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent molecule. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (MoleculeSchemaRef, optional, nullable)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### OligoConjugateLinkFieldDefinition

A schema field definition for linking to oligo conjugates.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent Oligo Conjugate. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (OligoConjugateSchemaRef, optional, nullable)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### OligoDuplexLinkFieldDefinition

A schema field definition for linking to oligo duplexes.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent Oligo Duplex. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (OligoDuplexSchemaRef, optional, nullable)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### ProteinLinkFieldDefinition

A schema field definition for linking to Proteins.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent Protein. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### RequestLinkFieldDefinition

A schema field definition for linking to assay requests.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### ResultLinkFieldDefinition

A schema field definition for linking to assay results.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (ResultSchemaRef, optional, nullable)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### RnaOligoLinkFieldDefinition

A schema field definition for linking to RNA oligos.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent RNA Oligo. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (RnaOligoSchemaRef, optional) — The linked item must be of this schema. This is required because we do not allow linking to a generic RNA Oligo.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### RnaPartLinkFieldDefinition

A schema field definition for linking to RNA parts.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent RNA sequence. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (ObjectRef, optional) — Union of RnaSequenceSchema, SystemCategory
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### RnaSequenceLinkFieldDefinition

A schema field definition for linking to RNA sequences.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent RNA sequence. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (RnaSequenceSchemaRef, optional) — The linked item must be of this schema. This is required because we do not allow linking to a generic RNA Sequence.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### RunLinkFieldDefinition

A schema field definition for linking to assay runs.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (RunSchemaRef, optional, nullable)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### StorableLinkFieldDefinition

A schema field definition for linking to storable inventory items.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### SystemCategoryLinkFieldDefinition

A schema field definition for linking to entities that implement a system category (static schema interface).

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### TextFieldDefinition

A field definition for short, single-line text values. Each field has a user-facing `name` and a `systemName` for warehouse and API access. For multi-line text with no length restrictions, see `LongTextFieldDefinition`.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### TranscriptionLinkFieldDefinition

A schema field definition for linking to transcriptions (RNA sequences created from DNA).

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent RNA sequence. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (RnaSequenceSchemaRef, optional)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### TranslationLinkFieldDefinition

A schema field definition for linking to translations (AA sequences created from RNA).

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable) — The reason this field definition was archived, if applicable.
- `archived` (boolean, optional) — Whether this field definition has been archived.
- `createdAt` (string, optional, nullable)
- `derivationType` (enum, optional) — How this field's value is determined: DIRECT (user-entered), COMPUTED (auto-calculated), or SNAPSHOT (frozen at creation).
  - Allowed values: `DIRECT`, `COMPUTED`, `SNAPSHOT`
- `description` (string, optional, nullable) — An optional user-provided description of this field definition.
- `id` (string, optional)
- `isMulti` (boolean, optional)
- `isParent` (boolean, optional) — Means the link is from a child to a parent AA sequence. Important for the registry's lot-numbering functionality.
- `isRequired` (boolean, optional) — When true, a value must be provided for this field when creating or updating an entity.
- `linkDefinition` (ObjectRef, optional) — Union of AaSequenceSchema, SystemCategory
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing display name of this field definition.
- `systemName` (string, optional) — The machine-readable identifier used as the warehouse column name and for API access.

### ObjectRef

- `__typename` (string, optional)
- `id` (string, optional)

### AaSequenceSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### CustomEntitySchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### UnitRef

- `__typename` (string, optional)
- `id` (string, optional)

### DnaOligoSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### DnaSequenceSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### DropdownRef

- `__typename` (string, optional)
- `id` (string, optional)

### EquipmentSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### FieldsetRef

- `__typename` (string, optional)
- `id` (string, optional)

### MixtureSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### MoleculeSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### OligoConjugateSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### OligoDuplexSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### ResultSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### RnaOligoSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### RnaSequenceSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

### RunSchemaRef

- `__typename` (string, optional)
- `id` (string, optional)

## Examples

**Response**

```json
{
  "items": [
    {
      "__typename": "__typename",
      "archiveReason": "archiveReason",
      "archived": true,
      "createdAt": "createdAt",
      "derivationType": "DIRECT",
      "description": "description",
      "id": "id",
      "isMulti": true,
      "isParent": true,
      "isRequired": true,
      "modifiedAt": "modifiedAt",
      "name": "name",
      "systemName": "systemName"
    }
  ]
}
```

**SDK Code**

```python
import requests

url = "https://{tenant_name}.benchling.com/api/v3/well-plate-schema/well_plate_schema_id/field-definitions/items"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.json())
```

```javascript
const url = 'https://{tenant_name}.benchling.com/api/v3/well-plate-schema/well_plate_schema_id/field-definitions/items';
const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```