> ## Documentation Index
> Fetch the complete documentation index at: https://docs.joinluminous.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Update unit class

> Update an existing unit class.



## OpenAPI

````yaml /api-reference/build.yaml post /unit-classes/{id}
openapi: 3.0.0
info:
  title: Luminous API
  version: 1.0.0
  description: API documentation for Luminous
servers:
  - url: https://{companyName}.api.joinluminous.com/external/api/v1
    variables:
      companyName:
        default: companyName
        description: Your company-specific subdomain
security: []
tags:
  - name: Products
    description: Get and manage products
  - name: Pricing
    description: Manage price schedules, levels, and customizations
  - name: BOMs
    description: Manage Bills of Materials (BOMs)
  - name: Labels
    description: Label rendering via Labelary ZPL service
  - name: Companies
    description: Manage business accounts and their associated data
  - name: Contacts
    description: Manage contact information for individuals
  - name: Suppliers
    description: Manage suppliers (factories) — vendors used on purchase orders
  - name: Supplier SKUs
    description: Manage per-supplier SKU and unit-cost overrides for products
  - name: Locations
    description: Manage warehouses and locations
  - name: Inventory
    description: Get and adjust product stock levels
  - name: Lots
    description: Create, update, and delete product lots (batches)
  - name: Transfer Orders
    description: Manage transfer orders
  - name: Fulfillment Orders
    description: Manage fulfillment orders and picklists
  - name: Purchase Orders
    description: Get and modify purchase orders
  - name: Receiving Reports
    description: Manage receiving reports
  - name: Payment Obligations
    description: Manage payment obligations for purchase orders
  - name: Sales Orders
    description: Manage sales orders and sales order shipments
  - name: Purgatory
    description: >-
      Inspect and resolve non-posted sales orders in the purgatory staging
      workflow
  - name: PickFlow Shipping
    description: >-
      Provider-agnostic shipping rates, services, packages, and label purchase
      for PickFlow
  - name: Cycle Counts
    description: >-
      Create, drive, and post PickFlow cycle counts — batches, per-warehouse
      sessions, and CSV import/export
  - name: Print Stations
    description: List paired print stations and enqueue print jobs to them
  - name: Invoices
    description: Get and manage invoices
  - name: Work Orders
    description: >-
      Manage work orders — production lifecycle, steps, materials, links,
      shipments, and comments
  - name: Production Batches
    description: Group and manage work orders as production batches
  - name: Bills
    description: >-
      Accounts payable bill management, payments, attachments, allocations, and
      variance
  - name: Prepayments
    description: Manage vendor prepayments and applications
  - name: Vendor Credits
    description: Manage vendor credits and applications
  - name: Vendor Returns
    description: Manage vendor returns and credit generation
  - name: Customer Returns
    description: Manage customer returns (sales returns), receiving, and restock behavior
  - name: Stock Snapshot
    description: Point-in-time stock snapshots with export support
  - name: Consumption
    description: Consumption reports and exports
  - name: Inventory Aging
    description: Cost-layer-based inventory aging reports
  - name: Bills Reports
    description: Accounts payable bills aging reports
  - name: Forecast
    description: Materialized forecast data
  - name: Reports
    description: Close the books, inventory discrepancy, transaction COGS, and EDI reports
  - name: Tags
    description: Add/remove tags across various resources
  - name: Custom Fields
    description: Get and set custom fields across various resources
  - name: Currency
    description: Currency configuration, exchange rates, and conversion
  - name: Integration Mappings
    description: Manage integration mappings for external systems
  - name: Integration Field Mappings
    description: Manage field-level mappings between Luminous and external systems
paths:
  /unit-classes/{id}:
    post:
      tags:
        - Unit Classes
      summary: Update unit class
      description: Update an existing unit class.
      operationId: updateUnitClass
      parameters:
        - in: path
          name: id
          required: true
          schema:
            type: integer
          description: Unit class ID
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - name
              properties:
                name:
                  type: string
                base_class:
                  type: boolean
      responses:
        '200':
          description: Updated
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: object
                    description: >-
                      A grouping of related units of measure (e.g. "Length",
                      "Weight"). Each class may have a base unit and a list of
                      UOMs.
                    properties:
                      id:
                        type: integer
                      created_at:
                        type: string
                        format: date-time
                      updated_at:
                        type: string
                        format: date-time
                      status:
                        type: string
                        nullable: true
                      name:
                        type: string
                      base_class:
                        type: boolean
                        description: True for the system base class (read-only).
                      unit_of_measures:
                        type: array
                        description: Present when the relation is loaded.
                        items:
                          type: object
                          description: >-
                            A single unit of measure (e.g. "Pound", "Kilogram")
                            belonging to a unit class.
                          properties:
                            id:
                              type: integer
                            created_at:
                              type: string
                              format: date-time
                            updated_at:
                              type: string
                              format: date-time
                            status:
                              type: string
                              nullable: true
                            unit_class_id:
                              type: integer
                            unit_class:
                              type: object
                              description: Present when the relation is loaded.
                              nullable: true
                              properties:
                                id:
                                  type: integer
                                name:
                                  type: string
                                base_class:
                                  type: boolean
                            name:
                              type: string
                            description:
                              type: string
                              nullable: true
                            base_unit:
                              type: boolean
                              description: True if this UOM is the base unit for its class.
                            unit_conversion_rules:
                              type: array
                              description: Present when the relation is loaded.
                              items:
                                type: object
                                description: >
                                  A rule converting from one unit of measure to
                                  another. `type=SYSTEM` rules apply globally
                                  for a class (e.g.

                                  1 lb = 0.453592 kg). `type=SKU` rules override
                                  system rules for a specific product
                                  (`product_id`).
                                properties:
                                  id:
                                    type: integer
                                  created_at:
                                    type: string
                                    format: date-time
                                  updated_at:
                                    type: string
                                    format: date-time
                                  status:
                                    type: string
                                    nullable: true
                                  base_unit_of_measure_id:
                                    type: integer
                                  base_unit_of_measure:
                                    type: object
                                    description: Present when the relation is loaded.
                                    nullable: true
                                    properties:
                                      id:
                                        type: integer
                                      name:
                                        type: string
                                      unit_class_id:
                                        type: integer
                                      base_unit:
                                        type: boolean
                                  converted_unit_of_measure_id:
                                    type: integer
                                  converted_unit_of_measure:
                                    type: object
                                    description: Present when the relation is loaded.
                                    nullable: true
                                    properties:
                                      id:
                                        type: integer
                                      name:
                                        type: string
                                      unit_class_id:
                                        type: integer
                                      base_unit:
                                        type: boolean
                                  conversion_factor:
                                    type: number
                                    description: >-
                                      Multiply a quantity in
                                      `base_unit_of_measure` by this factor to
                                      get the quantity in
                                      `converted_unit_of_measure`.
                                  type:
                                    type: string
                                    enum:
                                      - SYSTEM
                                      - SKU
                                  product_id:
                                    type: integer
                                    nullable: true
                                    description: >-
                                      Required when `type=SKU`; null when
                                      `type=SYSTEM`.
                                  product:
                                    type: object
                                    nullable: true
                                    description: >-
                                      Present when the relation is loaded. Shape
                                      mirrors the standard product resource.
                                    additionalProperties: true
                                  product_alternate_skus:
                                    type: array
                                    description: Present when the relation is loaded.
                                    items:
                                      type: object
                                      additionalProperties: true
                      base_unit_of_measure:
                        description: Present when the relation is loaded.
                        nullable: true
                        allOf:
                          - type: object
                            description: >-
                              A single unit of measure (e.g. "Pound",
                              "Kilogram") belonging to a unit class.
                            properties:
                              id:
                                type: integer
                              created_at:
                                type: string
                                format: date-time
                              updated_at:
                                type: string
                                format: date-time
                              status:
                                type: string
                                nullable: true
                              unit_class_id:
                                type: integer
                              unit_class:
                                type: object
                                description: Present when the relation is loaded.
                                nullable: true
                                properties:
                                  id:
                                    type: integer
                                  name:
                                    type: string
                                  base_class:
                                    type: boolean
                              name:
                                type: string
                              description:
                                type: string
                                nullable: true
                              base_unit:
                                type: boolean
                                description: >-
                                  True if this UOM is the base unit for its
                                  class.
                              unit_conversion_rules:
                                type: array
                                description: Present when the relation is loaded.
                                items:
                                  type: object
                                  description: >
                                    A rule converting from one unit of measure
                                    to another. `type=SYSTEM` rules apply
                                    globally for a class (e.g.

                                    1 lb = 0.453592 kg). `type=SKU` rules
                                    override system rules for a specific product
                                    (`product_id`).
                                  properties:
                                    id:
                                      type: integer
                                    created_at:
                                      type: string
                                      format: date-time
                                    updated_at:
                                      type: string
                                      format: date-time
                                    status:
                                      type: string
                                      nullable: true
                                    base_unit_of_measure_id:
                                      type: integer
                                    base_unit_of_measure:
                                      type: object
                                      description: Present when the relation is loaded.
                                      nullable: true
                                      properties:
                                        id:
                                          type: integer
                                        name:
                                          type: string
                                        unit_class_id:
                                          type: integer
                                        base_unit:
                                          type: boolean
                                    converted_unit_of_measure_id:
                                      type: integer
                                    converted_unit_of_measure:
                                      type: object
                                      description: Present when the relation is loaded.
                                      nullable: true
                                      properties:
                                        id:
                                          type: integer
                                        name:
                                          type: string
                                        unit_class_id:
                                          type: integer
                                        base_unit:
                                          type: boolean
                                    conversion_factor:
                                      type: number
                                      description: >-
                                        Multiply a quantity in
                                        `base_unit_of_measure` by this factor to
                                        get the quantity in
                                        `converted_unit_of_measure`.
                                    type:
                                      type: string
                                      enum:
                                        - SYSTEM
                                        - SKU
                                    product_id:
                                      type: integer
                                      nullable: true
                                      description: >-
                                        Required when `type=SKU`; null when
                                        `type=SYSTEM`.
                                    product:
                                      type: object
                                      nullable: true
                                      description: >-
                                        Present when the relation is loaded.
                                        Shape mirrors the standard product
                                        resource.
                                      additionalProperties: true
                                    product_alternate_skus:
                                      type: array
                                      description: Present when the relation is loaded.
                                      items:
                                        type: object
                                        additionalProperties: true
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                type: object
                properties:
                  message:
                    type: string
        '404':
          description: Unit class not found
          content:
            application/json:
              schema:
                type: object
                properties:
                  message:
                    type: string
        '422':
          description: Validation error
          content:
            application/json:
              schema:
                type: object
                properties:
                  message:
                    type: string
      security:
        - BearerAuth: []
components:
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      description: >-
        Authenticate using a bearer token. To create a token, navigate to
        /settings/api-tokens and click Create API Token.

````