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openapi: 3.2.0
info:
version: 1.0.0
title: Kantata OX API Documentation Custom Field Sets API
description: Kantata OX's API provides access to the majority of Kantata OX's data model.
termsOfService: https://www.kantata.com/terms-of-use
contact:
name: Kantata OX Support
url: https://knowledge.kantata.com/hc/en-us
license:
name: COPYRIGHT © 2026 Kantata, Inc.
url: https://www.kantata.com/terms-of-use
x-logo:
url: https://theme.zdassets.com/theme_assets/56104/04e93064d309f75d054b8cee885d1ea51e9be8f7.png
backgroundColor: '#FFFFFF'
altText: Kantata OX API Documentation
href: https://developer.kantata.com
servers:
- url: https://api.mavenlink.com/api/v1
tags:
- name: Custom Field Sets
description: 'Custom Field Sets contain custom fields and definitions of each fields'' subject type. The supported
subjects are currently *Workspace*, *Story*, *User*, and *WorkspaceGroup*.'
paths:
/custom_field_sets:
get:
summary: Fetching a list of Custom Field Sets
description: 'This endpoint returns structured Custom Field Set objects.
As with all Kantata OX API endpoints, the returned data will be referenced in sorted order in the `results` array
and will be indexed by ID in the `custom_field_sets` top-level JSON key.
Please see our Response Format section for more information.'
operationId: Get Custom Field Sets
tags:
- Custom Field Sets
parameters:
- in: query
name: created_after
description: Filter for records created after a specified datetime. The datetime must be in [ISO 8601](https://www.w3.org/TR/NOTE-datetime) format.
schema:
type: string
format: date-time
- in: query
name: created_before
description: Filter for records created before a specified datetime. The datetime must be in [ISO 8601](https://www.w3.org/TR/NOTE-datetime) format.
schema:
type: string
format: date-time
- in: query
name: external_reference_external_message
description: Filter the objects based on the external message of their associated external references. This is an exact match.
schema:
type: string
- in: query
name: external_reference_external_status
description: Filter by the status of the external object in the external system.
schema:
type: string
- in: query
name: external_reference_service_model
description: Filter by the type of the external object this external reference belongs to.
schema:
type: string
- in: query
name: external_reference_service_model_ref
description: Filter by the id of the external object this external reference belongs to.
schema:
type: integer
format: int32
- in: query
name: external_reference_service_model_refs
description: Filter for objects that correlate to the specified external object IDs. Provide a comma-separated list of up to 200 external IDs.
schema:
type: string
- in: query
name: external_reference_service_name
description: Filter by the name of the provider for integration.
schema:
type: string
- in: query
name: external_reference_status
description: Filter by the status of the integration, this can be successful or fail.
schema:
type: string
- in: query
name: has_external_references
description: Filter by whether or not the object has external references.
schema:
type: boolean
- in: query
name: include
description: 'Any of the below associations can be included in your request by providing the `include` param, e.g. `include=association1,association2`.
- `custom_fields` (CustomField) - The custom fields that belonging to the custom field set.
- `external_references` (ExternalReference) - Includes references to external integrations for this object.'
schema:
type: string
- in: query
name: only
description: 'Allows you to request one or more resources directly by ID. Multiple IDs can be supplied
in a comma separated list, like `GET /api/v1/workspaces.json?only=5,6,7`.'
schema:
type: string
- in: query
name: order
description: 'Supply `order` with the name of a valid sort field for the endpoint and a direction.
Valid values: `alphabetical:asc`, `alphabetical:desc`, `created_at:asc`, and `created_at:desc`.'
schema:
type: string
default: created_at:desc
- in: query
name: page
schema:
type: integer
format: int32
default: 1
- in: query
name: per_page
schema:
type: integer
format: int32
default: 20
maximum: 200
- in: query
name: updated_after
description: Filter for records updated after a specified datetime. The datetime must be in [ISO 8601](https://www.w3.org/TR/NOTE-datetime) format.
schema:
type: string
format: date-time
- in: query
name: updated_before
description: Filter for records updated before a specified datetime. The datetime must be in [ISO 8601](https://www.w3.org/TR/NOTE-datetime) format.
schema:
type: string
format: date-time
- in: query
name: with_subject_type
description: 'Set by a specific subject type: Workspace, Story, User or WorkspaceGroup.'
schema:
type: string
- in: query
name: without_external_reference_service_name
description: Exclude by the existence of an external reference with the specified service name.
schema:
type: string
responses:
'200':
description: A list of Custom Field Sets have been retrieved.
content:
application/json:
schema:
type: object
properties:
count:
type: integer
format: int32
meta:
type: object
properties:
count:
type: integer
format: int32
page_count:
type: integer
format: int32
page_number:
type: integer
format: int32
page_size:
type: integer
format: int32
results:
type: array
items:
type: object
properties:
key:
type: string
id:
type: string
custom_field_sets:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomFieldSet'
external_references:
type: object
additionalProperties:
$ref: '#/components/schemas/ExternalReference'
custom_fields:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomField'
'400':
description: Bad Request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'401':
description: Unauthorized request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'403':
description: Forbidden request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'404':
description: Page Not Found
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'422':
description: Unprocessable Entity
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'503':
description: Service is unavailable
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
post:
summary: Creating a new Custom Field Set
description: 'To create a custom field, the current user must be the Account Administrator.
This endpoint returns structured Custom Field Set objects.
As with all Kantata OX API endpoints, the returned data will be referenced in sorted order in the `results` array
and will be indexed by ID in the `custom_field_sets` top-level JSON key.
Please see our Response Format section for more information.'
operationId: Create Custom Field Set
tags:
- Custom Field Sets
parameters:
- in: query
name: include
description: 'Any of the below associations can be included in your request by providing the `include` param, e.g. `include=association1,association2`.
- `custom_fields` (CustomField) - The custom fields that belonging to the custom field set.
- `external_references` (ExternalReference) - Includes references to external integrations for this object.'
schema:
type: string
responses:
'200':
description: Custom Field Set has been created.
content:
application/json:
schema:
type: object
properties:
count:
type: integer
format: int32
meta:
type: object
properties:
count:
type: integer
format: int32
page_count:
type: integer
format: int32
page_number:
type: integer
format: int32
page_size:
type: integer
format: int32
results:
type: array
items:
type: object
properties:
key:
type: string
id:
type: string
custom_field_sets:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomFieldSet'
external_references:
type: object
additionalProperties:
$ref: '#/components/schemas/ExternalReference'
custom_fields:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomField'
'400':
description: Bad Request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'401':
description: Unauthorized request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'403':
description: Forbidden request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'404':
description: Page Not Found
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'422':
description: Unprocessable Entity
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'503':
description: Service is unavailable
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
requestBody:
content:
application/json:
schema:
type: object
properties:
custom_field_set:
type: object
properties:
name:
type: string
description: The name of the custom field set.
subject_type:
type: string
description: 'The type of objects contained by the custom field set. The supported subjects
are currently Workspace, Story, User, and WorkspaceGroup.'
required:
- name
- subject_type
required: true
/custom_field_sets/{id}:
get:
summary: Fetching a single Custom Field Set
description: 'This endpoint returns structured Custom Field Set objects.
As with all Kantata OX API endpoints, the returned data will be referenced in sorted order in the `results` array
and will be indexed by ID in the `custom_field_sets` top-level JSON key.
Please see our Response Format section for more information.'
operationId: Get Custom Field Set
tags:
- Custom Field Sets
parameters:
- in: path
name: id
required: true
description: The ID of the Model.
schema:
type: integer
- in: query
name: include
description: 'Any of the below associations can be included in your request by providing the `include` param, e.g. `include=association1,association2`.
- `custom_fields` (CustomField) - The custom fields that belonging to the custom field set.
- `external_references` (ExternalReference) - Includes references to external integrations for this object.'
schema:
type: string
responses:
'200':
description: The Custom Field Set has been retrieved.
content:
application/json:
schema:
type: object
properties:
count:
type: integer
format: int32
meta:
type: object
properties:
count:
type: integer
format: int32
page_count:
type: integer
format: int32
page_number:
type: integer
format: int32
page_size:
type: integer
format: int32
results:
type: array
items:
type: object
properties:
key:
type: string
id:
type: string
custom_field_sets:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomFieldSet'
external_references:
type: object
additionalProperties:
$ref: '#/components/schemas/ExternalReference'
custom_fields:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomField'
'400':
description: Bad Request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'401':
description: Unauthorized request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'403':
description: Forbidden request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'404':
description: Page Not Found
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'422':
description: Unprocessable Entity
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'503':
description: Service is unavailable
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
put:
summary: Updating an existing Custom Field Set
description: 'To update a custom field, the current user must be the Account Administrator.
NOTE: `subject_type` cannot be changed.
This endpoint returns structured Custom Field Set objects.
As with all Kantata OX API endpoints, the returned data will be referenced in sorted order in the `results` array
and will be indexed by ID in the `custom_field_sets` top-level JSON key.
Please see our Response Format section for more information.'
operationId: Update Custom Field Set
tags:
- Custom Field Sets
parameters:
- in: path
name: id
required: true
description: The ID of the Model.
schema:
type: integer
- in: query
name: include
description: 'Any of the below associations can be included in your request by providing the `include` param, e.g. `include=association1,association2`.
- `custom_fields` (CustomField) - The custom fields that belonging to the custom field set.
- `external_references` (ExternalReference) - Includes references to external integrations for this object.'
schema:
type: string
responses:
'200':
description: Custom Field Set has been updated.
content:
application/json:
schema:
type: object
properties:
count:
type: integer
format: int32
meta:
type: object
properties:
count:
type: integer
format: int32
page_count:
type: integer
format: int32
page_number:
type: integer
format: int32
page_size:
type: integer
format: int32
results:
type: array
items:
type: object
properties:
key:
type: string
id:
type: string
custom_field_sets:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomFieldSet'
external_references:
type: object
additionalProperties:
$ref: '#/components/schemas/ExternalReference'
custom_fields:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomField'
'400':
description: Bad Request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'401':
description: Unauthorized request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'403':
description: Forbidden request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'404':
description: Page Not Found
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'422':
description: Unprocessable Entity
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'503':
description: Service is unavailable
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
requestBody:
content:
application/json:
schema:
type: object
properties:
custom_field_set:
type: object
properties:
name:
type: string
description: The name of the custom field set.
subject_type:
type: string
description: Subject type cannot be changed.
required: true
delete:
summary: Deleting an existing Custom Field Set
description: 'The response will contain no content and an HTTP 204 status code if the request was
successful, or a standard Kantata OX error message explaining why the object could not be deleted.'
operationId: Delete Custom Field Set
tags:
- Custom Field Sets
parameters:
- in: path
name: id
required: true
description: The ID of the Model.
schema:
type: integer
responses:
'204':
description: Custom Field Set has been deleted.
'400':
description: Bad Request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'401':
description: Unauthorized request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'403':
description: Forbidden request
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'404':
description: Page Not Found
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'422':
description: Unprocessable Entity
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
'503':
description: Service is unavailable
content:
application/json:
schema:
$ref: '#/components/schemas/Errors'
components:
schemas:
ExternalReference:
title: External Reference
description: 'External References allows users see which objects (one of `Assignment`, `BillingMilestone`, `CustomField`, `CustomFieldChoice`, `CustomFieldSet`, `CustomFieldValue`, `Estimate`, `EstimateScenario`, `EstimateScenarioResource`, `Expense`, `ExpenseBudget`, `Invoice`, `Participation`, `Post`, `RateCard`, `Role`, `Skill`, `StatusReport`, `Story`, `StoryAllocationDay`, `Submission`, `SurveyAnswer`, `SurveyQuestion`, `SurveyResponse`, `SurveyTemplate`, `TimeEntry`, `TimeOffEntry`, `User`, `Vendor`, `Workspace`, `WorkspaceAllocation`, `WorkspaceGroup`, or `WorkspaceResource`
are synced with third party systems. This allows you to view the sync status of items in addition to the integration
specifics for a synced object.
Objects that are synced with a third party system have external integration
attributes that include the corresponding ID of the third party object with
which it is synced, a link that allows you to view the object in the third
party system, the status of the external object in the external system,
the status of the sync, and a link to exceptions.'
type: object
properties:
created_at:
type: string
format: date-time
description: The date and time the reference was created.
external_link:
type: string
description: A URL that links to either the external object or event.
external_message:
type: string
description: An optional message about the external object.
external_status:
type: string
description: The status of the external object in the external system.
last_synced_at:
type: string
format: date-time
locked:
type: boolean
description: 'An optional field, indicating whether the subject should be locked. To prevent changes to the
object in Kantata OX, set this to true. This currently only applies to expense report rejections.'
service_model:
type: string
description: The type of the external object to which this reference belongs.
service_model_ref:
type: string
description: The ID of the external object to which this reference belongs.
service_name:
type: string
description: The provider name of the integration.
status:
type: string
description: The status of the integration. Options are 'pending', 'successful', or 'failed'.
subject_id:
type: integer
format: int32
description: The ID of the Kantata OX object to which this external reference belongs.
subject_ref:
type: object
description: '`subject_ref` will only be included in the response if `subject` is in the list of included associations. See <a href=''#section/Includes''>include</a> section for usage.'
properties:
key:
type: string
id:
type: string
subject_type:
type: string
description: 'The type of Kantata OX object to which this external reference belongs.
One of `Assignment`, `BillingMilestone`, `CustomField`, `CustomFieldChoice`, `CustomFieldSet`, `CustomFieldValue`, `Estimate`, `EstimateScenario`, `EstimateScenarioResource`, `Expense`, `ExpenseBudget`, `Invoice`, `Participation`, `Post`, `RateCard`, `Role`, `Skill`, `StatusReport`, `Story`, `StoryAllocationDay`, `Submission`, `SurveyAnswer`, `SurveyQuestion`, `SurveyResponse`, `SurveyTemplate`, `TimeEntry`, `TimeOffEntry`, `User`, `Vendor`, `Workspace`, `WorkspaceAllocation`, `WorkspaceGroup`, or `WorkspaceResource`.'
updated_at:
type: string
format: date-time
description: The date and time the reference was last updated.
CustomField:
title: Custom Field
description: 'The [Custom Fields](https://mavenlink.zendesk.com/hc/en-us/articles/202924760-Custom-Fields-Overview-#arrange) object allows you to
view, create, update, and delete extra fields for additional Estimate, Project, Group, Resource, Task, and User information.
If Custom Fields represent the fields themselves, [Custom Field Values](/tag/Custom-Field-Values)
represent the values in/of those fields.'
type: object
properties:
choice_ids:
type: array
items:
type: string
description: '`choice_ids` will only be included in the response if `choices` is in the list of included associations. See <a href=''#section/Includes''>include</a> section for usage.'
created_at:
type: string
format: date-time
creator_id:
type: string
description: '`creator_id` will only be included in the response if `creator` is in the list of included associations. See <a href=''#section/Includes''>include</a> section for usage.'
custom_field_set_id:
type: string
description: '`custom_field_set_id` will only be included in the response if `custom_field_set` is in the list of included associations. See <a href=''#section/Includes''>include</a> section for usage.'
default_text:
type: string
description: 'The message in an empty custom field, before a `string`, `date`, `number`, or `currency` value is entered in.
This only appears in the UI.
Visible when whether the custom field is an input field..'
external_reference_ids:
type: array
items:
type: string
description: '`external_reference_ids` will only be included in the response if `external_references` is in the list of included associations. See <a href=''#section/Includes''>include</a> section for usage.'
name:
type: string
description: The name of the custom field.
read_access:
type: integer
format: int32
description: "The `read_access` [permission setting on each custom field](https://mavenlink.zendesk.com/hc/en-us/articles/202924760#see)\ndetermines the minimum permission needed to view a custom field and its value.\n* `Workspace` (Project), `Resource`, and `Story` (Task) custom fields are project-specific objects,\nso their minimum permissions are set at the [project level](https://mavenlink.zendesk.com/hc/en-us/articles/115002779293-Project-Permissions):\n - `project_collaboration` (default)\n - `time_logging`\n - `financial`\n - `project_admin`\n\nMost account-level permissions supercede project-level permissions. Therefore, Account Administrators\nare able to view all Project, Resource, and Task custom fields and values across the account,\nregardless of project participation or `read_access` settings.\n* `Estimate`, `WorkspaceGroup` (Group), and `User` custom fields are account-wide objects,\nso their minimum permissions are set at the [account level](https://mavenlink.zendesk.com/hc/en-us/articles/203041364):\n - `account_collaboration`\n - `project_creator`\n - `project_lead`\n - `reports_viewer`\n - `reports_viewer_with_cost`\n - `account_admin` (default)."
unique_constraint:
type: boolean
description: 'Indicates whether a custom field value must be unique across Estimates, Projects, Groups, Resources, Tasks, or Users.
This is set to `false` by default.
Does not apply to Custom Fields with choices.
Visible when whether the custom field is an input field..'
updated_at:
type: string
format: date-time
value_type:
type: string
description: "The format of the [custom field's value](/tag/Custom-Field-Values):\n | Value Type | Format | Sample |\n | -------------------- |:----------------------------------------:| --------------:|\n | `string` | `<text_string>` | `\"foo\"` |\n | `date` | `<ISO_8601 Date Format>` | `\"2014-02-25\"` |\n | `number` | `<integer_value>` | `13` |\n | `currency` | `[<int_value_in_cents>, <currency_code>]`| `[998, \"USD\"]` |\n | `single` and `multi` | `[<choice_ids>]` | `[1, 2, 4]` |\n\nThis is set to `string`, by default."
write_access:
type: integer
format: int32
description: The permission level required for a user to create, update, or delete a custom field's value.
CustomFieldSet:
title: Custom Field Set
description: 'Custom Field Sets contain custom fields and definitions of each fields'' subject type. The supported
subjects are currently Estimate, Project, Project Group, Resource, Task, and User.'
type: object
properties:
created_at:
type: string
format: date-time
custom_field_ids:
type: array
items:
type: string
description: '`custom_field_ids` will only be included in the response if `custom_fields` is in the list of included associations. See <a href=''#section/Includes''>include</a> section for usage.'
external_ref
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# Full source: https://raw.githubusercontent.com/api-evangelist/mavenlink/refs/heads/main/openapi/mavenlink-custom-field-sets-api-openapi.yml