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

# Update custom field

> Update a custom field's name, required flag, default, or options. The type can't change, except between dropdown and multiselect. Options that tasks still use can't be removed or renamed; the request is rejected instead of changing task values.



## OpenAPI

````yaml /openapi.json put /custom-field/{id}
openapi: 3.1.0
info:
  title: Kaneo API
  version: 1.0.0
  description: Kaneo Project Management API - Manage projects, tasks, labels, and more
servers:
  - url: https://cloud.kaneo.app/api
    description: Kaneo API Server
security:
  - bearerAuth: []
paths:
  /custom-field/{id}:
    put:
      tags:
        - Custom Fields
      summary: Update custom field
      description: >-
        Update a custom field's name, required flag, default, or options. The
        type can't change, except between dropdown and multiselect. Options that
        tasks still use can't be removed or renamed; the request is rejected
        instead of changing task values.
      operationId: updateCustomField
      parameters:
        - schema:
            type: string
          required: true
          name: id
          in: path
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                name:
                  type: string
                  description: New name for the field. Cannot be blank.
                type:
                  type: string
                  enum:
                    - text
                    - number
                    - date
                    - dropdown
                    - boolean
                    - multiselect
                  description: >-
                    Only `dropdown` and `multiselect` can switch between each
                    other. Task values are converted, and switching to
                    `dropdown` is rejected while a task has more than one option
                    picked. Any other type change is rejected.
                required:
                  type: boolean
                  description: >-
                    Whether every task must have a value. Turning it on needs a
                    default, which fills tasks that have no value yet.
                defaultValue:
                  type:
                    - string
                    - 'null'
                  description: >-
                    Value new tasks start with. Send `null` or an empty string
                    to clear it. Multiselect defaults are a JSON array of
                    options.
                options:
                  type: array
                  items:
                    type: string
                  description: >-
                    The full option list for dropdown and multiselect fields, in
                    display order. Adding and reordering options is always
                    allowed. Removing or renaming an option that a task still
                    uses is rejected with 400, so task values are never changed
                    silently.
      responses:
        '200':
          description: The updated custom field
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CustomFieldDefinition'
        '400':
          description: >-
            Invalid body, a type change, or removing an option that tasks still
            use
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
        '401':
          description: Missing or invalid credentials
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
        '403':
          description: No access to the project, or missing project:update permission
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
        '404':
          description: Custom field not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
        '429':
          $ref: '#/components/responses/ApiKeyRateLimited'
components:
  schemas:
    CustomFieldDefinition:
      type: object
      properties:
        id:
          type: string
        projectId:
          type: string
        name:
          type: string
        type:
          type: string
        required:
          type: boolean
        defaultValue:
          type:
            - string
            - 'null'
        options: {}
        position:
          type: number
        createdAt:
          type: string
          format: date-time
        updatedAt:
          type: string
          format: date-time
      required:
        - id
        - projectId
        - name
        - type
        - required
        - defaultValue
        - position
        - createdAt
        - updatedAt
    ApiError:
      type: object
      properties:
        message:
          type: string
          description: Human-readable description of the error.
          example: Task not found
        code:
          type: string
          description: >-
            Stable UPPER_SNAKE_CASE code. Derived from the status unless a more
            specific code applies, such as VALIDATION_ERROR or
            MISSING_PERMISSION.
          example: NOT_FOUND
        issues:
          type: array
          items:
            type: object
            properties:
              path:
                type: string
                description: >-
                  Dotted path to the invalid input, prefixed with the request
                  part (body, query, params, header).
                example: body.title
              message:
                type: string
                example: Required
            required:
              - path
              - message
          description: Every validation issue, for VALIDATION_ERROR.
        missingPermissions:
          type: array
          items:
            type: string
          description: >-
            Permissions the caller lacks for this route, as resource:action, for
            MISSING_PERMISSION and API_KEY_SCOPE.
          example:
            - task:update
      required:
        - message
        - code
  responses:
    ApiKeyRateLimited:
      description: >-
        The API key exceeded its rate limit or usage quota. Wait the number of
        seconds in Retry-After before retrying. The X-RateLimit headers are sent
        only when the rate limit was hit.
      headers:
        Retry-After:
          description: >-
            Seconds to wait before retrying. Omitted when an exhausted usage
            quota never refills.
          schema:
            type: integer
        X-RateLimit-Limit:
          description: Requests the API key may make per window.
          schema:
            type: integer
        X-RateLimit-Remaining:
          description: Requests left in the current window.
          schema:
            type: integer
        X-RateLimit-Reset:
          description: Unix time in seconds when the current window resets.
          schema:
            type: integer
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: API key or session token (Bearer)

````

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