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

> ## Agent Instructions
> Flowsign is one word with a lowercase s.
> The REST API base URL is https://my.flowsign.app and every endpoint lives under /api/v1.
> When answering API questions, cite the HTTP method and endpoint path.
> API access needs the Enterprise plan and an API key with the API access permission.

# List custom fields

> Returns the organisation's active custom field definitions in display order. A plan without custom fields answers 402.



## OpenAPI

````yaml /api-reference/openapi.json get /api/v1/custom-fields
openapi: 3.0.3
info:
  title: Flowsign API
  version: 1.0.0
  description: >-
    Public v1 API for Flowsign. Every endpoint is authenticated with a Bearer
    API key (prefix `fsk_`). Errors use `{ error, details? }`; success responses
    wrap payload data as `{ data }`.


    An organisation is divided into workspaces. A key is issued for one
    workspace and acts there on every request (see `GET /api/v1/workspaces`);
    `X-Workspace-Id` is optional and may only name that workspace. Packages,
    templates, contacts and members are scoped to the key's workspace.
servers:
  - url: https://my.flowsign.app
    description: Production
security:
  - ApiKey: []
paths:
  /api/v1/custom-fields:
    get:
      tags:
        - Custom fields
      summary: List custom fields
      description: >-
        Returns the organisation's active custom field definitions in display
        order. A plan without custom fields answers 402.
      operationId: getCustom-fields
      parameters:
        - schema:
            type: string
            minLength: 1
            description: >-
              Narrows the list to the fields a package launched from this
              template carries: every `all` scope field plus the `templates`
              scope fields that name it.
            example: kX9dQ2mB7pLw
          required: false
          name: templateId
          in: query
        - schema:
            type: string
            description: >-
              The workspace the key was issued for, as returned by `GET
              /api/v1/workspaces`. Optional: omitting it acts in the key's
              workspace, and any other id is rejected with 401.
          required: false
          name: x-workspace-id
          in: header
      responses:
        '200':
          description: Success
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: array
                    items:
                      type: object
                      properties:
                        key:
                          type: string
                          description: >-
                            The key a package's `metadata` uses for this field.
                            Lowercase letters, digits and underscores, unique
                            within the organisation.
                          example: cost_centre
                        label:
                          type: string
                          description: The name shown for the field in the app.
                          example: Cost centre
                        helpText:
                          type: string
                          nullable: true
                          description: >-
                            Guidance shown alongside the field, or null when
                            none is set.
                          example: The cost centre this agreement is billed to.
                        isRequired:
                          type: boolean
                          description: >-
                            Whether a value must be set before a package
                            carrying the field is sent.
                          example: true
                        scope:
                          type: string
                          enum:
                            - all
                            - templates
                          description: >-
                            Which packages carry the field: `all` for every
                            package, `templates` for only packages launched from
                            one of `templateIds`.
                          example: templates
                        templateIds:
                          type: array
                          items:
                            type: string
                          description: >-
                            For `templates` scope, the templates whose packages
                            carry the field. Empty for `all` scope.
                          example:
                            - kX9dQ2mB7pLw
                        order:
                          type: integer
                          description: >-
                            Zero-based display position among the organisation's
                            custom fields.
                          example: 0
                      required:
                        - key
                        - label
                        - helpText
                        - isRequired
                        - scope
                        - templateIds
                        - order
                required:
                  - data
        '401':
          description: Missing or invalid API key
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '402':
          description: Caller's plan does not include this feature (publicApi / webhooks)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '403':
          description: API key present but caller lacks the required permission
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '422':
          description: Request failed schema validation; details keyed by field
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '429':
          description: Rate limit exceeded; see `Retry-After`
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
components:
  schemas:
    Error:
      type: object
      properties:
        error:
          type: string
          description: What went wrong, in plain words.
          example: 'Missing permission: canSendPackages'
        details:
          type: object
          additionalProperties:
            type: array
            items:
              type: string
          description: >-
            Validation problems keyed by field path. Present only on 422
            responses.
          example:
            recipients.0.email:
              - Invalid email
      required:
        - error
  securitySchemes:
    ApiKey:
      type: http
      scheme: bearer
      bearerFormat: fsk_*

````