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openapi: 3.2.0
info:
version: 1.0.0
title: Kantata OX API Documentation Custom Field Values 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 Values
description: 'If Custom Fields represent the fields themselves,
Custom Field Values represent the values in/of those fields. The Custom Field Values object allows
you to view, create, update, and delete these values.'
paths:
/custom_field_values:
get:
summary: Fetching a list of Custom Field Values
description: 'Returns all values for the specified set of
Custom Fields.
This endpoint has its own rate limit. See the Knowledge Base for more information.
Custom fields are organized into sets,
by the objects they store additional information for (Estimate, Project, Group, Resource, Task, or User).
Use the `subject_type` parameter to specify which set of Custom Fields to return values for:
* `Estimate`
* `Story` (Task)
* `User`
* `Workspace` (Project)
* `WorkspaceGroup` (Group)
* `Resource`
Custom field values for _archived_ Projects and Tasks are included in returned values.
Values are sorted from less to more recently updated.
##### Note:
The `read_access` permission setting on each custom field
determines the minimum permission needed to view a custom field and its value.
* `Workspace` (Project), `Resource`, and `Story` (Task) custom fields are project-specific objects,
so their minimum permissions are set at the project level:
- `project_collaboration` (default)
- `time_logging`
- `financial`
- `project_admin`
Most account-level permissions supercede project-level permissions. Therefore, Account Administrators
are able to view all Project, Resource, and Task custom fields and values across the account,
regardless of project participation or `read_access` settings.
* `Estimate`, `WorkspaceGroup` (Group), and `User` custom fields are account-wide objects, so their minimum permissions are
set at the account level:
- `account_collaboration`
- `project_creator`
- `project_lead`
- `reports_viewer`
- `reports_viewer_with_cost`
- `account_admin` (default)
This endpoint returns structured Custom Field Value 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_values` top-level JSON key.
Please see our Response Format section for more information.'
operationId: Get Custom Field Values
tags:
- Custom Field Values
parameters:
- in: query
name: subject_type
required: true
description: 'You must specify which set of Custom Fields to return values for:
* `Estimate`
* `Story` (Task)
* `User`
* `Workspace` (Project)
* `WorkspaceGroup` (Group)
* `Resource`
This parameter is required.'
schema:
type: string
- 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_field` (CustomField) - Retrieves the custom field the value is for. The response will include `custom_field_id`, which references the data in the `custom_fields` top-level key.
- `external_references` (ExternalReference) - Includes references to external integrations for this object.
- `selected_choices` (CustomFieldChoice) - Retrieves the custom field choice that corresponds to the custom field value. The response will include `selected_choice_ids`, which references the data in the `custom_field_choices` top-level key.
- `setter` (User) - Retrieves the user that set the custom field value. The response will include `setter_id`, which references the data in the `users` top-level key.
- `subject` (polymorphic) - Retrieves the object which the custom field value is for. The response will include `subject_ref`, which references the data in the top-level key specified in the `key` field of `subject_ref`. The possible objects are as follows:
* `Estimate`
* `Workspace` (Project)
* `WorkspaceGroup` (Group)
* `Resource`
* `Story` (Task)
* `User`.'
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: `created_at:asc`, `created_at:desc`, `subject_id:asc`, `subject_id:desc`, `updated_at:asc`, and `updated_at:desc`.'
schema:
type: string
default: created_at:asc
- 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_custom_field_id
description: Filters for values of the Custom Field(s) with the specified ID(s). Give multiple Custom Field IDs in a comma-separated list.
schema:
type: string
- in: query
name: with_setter_id
description: Filters for Custom Field Values set by a user with the specified ID(s). Give multiple user IDs in a comma-separated list.
schema:
type: string
- in: query
name: with_subject_id
description: "Filters for Custom Field Values associated with the specified ID(s) of an Estimate, Project,\n Group, Resource, Task, or User. Give multiple IDs in a comma-separated list."
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 Values 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_values:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomFieldValue'
external_references:
type: object
additionalProperties:
$ref: '#/components/schemas/ExternalReference'
custom_fields:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomField'
users:
type: object
additionalProperties:
$ref: '#/components/schemas/User'
custom_field_choices:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomFieldChoice'
stories:
type: object
additionalProperties:
$ref: '#/components/schemas/Story'
workspaces:
type: object
additionalProperties:
$ref: '#/components/schemas/Workspace'
workspace_groups:
type: object
additionalProperties:
$ref: '#/components/schemas/WorkspaceGroup'
'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 Value
description: 'Creates a new value for the specified custom field. Creating a value can also override existing values,
effectively making this an update request as well.
When creating new single or multi choice values that
override existing values, note that new values are not _added_ to existing values, but instead _replace_ existing values.
Additionally, every new value has a unique, new ID.
This endpoint has its own rate limit. See the Knowledge Base for more information.
**Bulk Create or Update**
This endpoint supports bulk creating or updating up to 100 objects. In the request body, set the top-level key to its plural form and place the objects in an array. Example:
```
{
"custom_field_values": [
{
"subject_type": "Workspace",
"subject_id": 123,
"custom_field_id": 456,
"value": "Hello world"
},
{
"subject_type": "Workspace",
"subject_id": 123,
"custom_field_id": 789,
"value": "Hello world"
}
]
}
```
This endpoint returns structured Custom Field Value 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_values` top-level JSON key.
Please see our Response Format section for more information.'
operationId: Create Custom Field Value
tags:
- Custom Field Values
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_field` (CustomField) - Retrieves the custom field the value is for. The response will include `custom_field_id`, which references the data in the `custom_fields` top-level key.
- `external_references` (ExternalReference) - Includes references to external integrations for this object.
- `selected_choices` (CustomFieldChoice) - Retrieves the custom field choice that corresponds to the custom field value. The response will include `selected_choice_ids`, which references the data in the `custom_field_choices` top-level key.
- `setter` (User) - Retrieves the user that set the custom field value. The response will include `setter_id`, which references the data in the `users` top-level key.
- `subject` (polymorphic) - Retrieves the object which the custom field value is for. The response will include `subject_ref`, which references the data in the top-level key specified in the `key` field of `subject_ref`. The possible objects are as follows:
* `Estimate`
* `Workspace` (Project)
* `WorkspaceGroup` (Group)
* `Resource`
* `Story` (Task)
* `User`.'
schema:
type: string
responses:
'200':
description: Custom Field Value 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_values:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomFieldValue'
external_references:
type: object
additionalProperties:
$ref: '#/components/schemas/ExternalReference'
custom_fields:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomField'
users:
type: object
additionalProperties:
$ref: '#/components/schemas/User'
custom_field_choices:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomFieldChoice'
stories:
type: object
additionalProperties:
$ref: '#/components/schemas/Story'
workspaces:
type: object
additionalProperties:
$ref: '#/components/schemas/Workspace'
workspace_groups:
type: object
additionalProperties:
$ref: '#/components/schemas/WorkspaceGroup'
'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_value:
type: object
properties:
subject_type:
type: string
description: 'You must specify which set of Custom Fields to return values for:
* `Estimate`
* `Story` (Task)
* `User`
* `Workspace` (Project)
* `WorkspaceGroup` (Group)
* `Resource`
This parameter is required.'
subject_id:
type: integer
format: int32
description: The ID of the Estimate, Project, Group, Resource, Task, or User the custom field is for.
custom_field_id:
type: integer
format: int32
description: The ID of the Custom Field to create or update the value for.
value:
type: string
description: 'The value to create or update to for the specified custom field.
Values can be created or updated in these formats:
| Value Type | Format | Sample |
| -------------------- |:----------------------------------------:| --------------:|
| `string` | `<text_string>` | `"foo"` |
| `date` | `<ISO_8601 Date Format>` | `"2014-02-25"` |
| `number` | `<integer_value>` | `13` |
| `currency` | `[<int_value_in_cents>, <currency_code>]`| `[998, "USD"]` |
| `single` and `multi` | `[<choice_ids>]` | `[1, 2, 4]` |
##### Note:
The `write_access` [permission setting on each custom field](https://mavenlink.zendesk.com/hc/en-us/articles/202924760#see)
determines the minimum permission needed to edit the value of each custom field.
* Editing `Workspace` (Project), `Resource`, and `Story` (Task) custom fields are project-specific changes,
so permissions are set at the project level:
- `project_collaboration`
- `time_logging`
- `financial`
- `project_admin` (default)
Most account-level permissions supercede project-level permissions. Therefore, Account Administrators
are able to edit all Project, Resource, and Task custom fields and values across the account,
regardless of project participation or `write_access` settings.
* Editing `Estimate`, `WorkspaceGroup` (Group), and `User` custom fields are account-wide changes,
so permissions are set at the account level:
- `account_collaboration`
- `project_creator`
- `project_lead`
- `reports_viewer`
- `reports_viewer_with_cost`
- `account_admin` (default).'
required:
- subject_type
- subject_id
- custom_field_id
- value
required: true
delete:
summary: Delete multiple custom field values
description: 'The IDs of the custom field values to delete can be provided in the `ids` query parameter or via the request body.
Request body example:
```{
"ids": "1,2,3"
}```
If any specified custom field values cannot be deleted, the entire request will fail and an error message
will be returned that specifies which ones could not be deleted and why.
This endpoint returns structured Custom Field Value 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_values` top-level JSON key.
Please see our Response Format section for more information.'
operationId: Delete Custom Field Values
tags:
- Custom Field Values
parameters:
- in: query
name: ids
required: false
description: 'A comma-separated list of IDs of custom field values. You can provide up to 100 IDs. The IDs can be
provided in this query parameter or via the request body.'
schema:
type: string
responses:
'204':
description: Custom Field Value 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'
/custom_field_values/{id}:
get:
summary: Fetching a single Custom Field Value
description: 'This endpoint returns structured Custom Field Value 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_values` top-level JSON key.
Please see our Response Format section for more information.'
operationId: Get Custom Field Value
tags:
- Custom Field Values
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_field` (CustomField) - Retrieves the custom field the value is for. The response will include `custom_field_id`, which references the data in the `custom_fields` top-level key.
- `external_references` (ExternalReference) - Includes references to external integrations for this object.
- `selected_choices` (CustomFieldChoice) - Retrieves the custom field choice that corresponds to the custom field value. The response will include `selected_choice_ids`, which references the data in the `custom_field_choices` top-level key.
- `setter` (User) - Retrieves the user that set the custom field value. The response will include `setter_id`, which references the data in the `users` top-level key.
- `subject` (polymorphic) - Retrieves the object which the custom field value is for. The response will include `subject_ref`, which references the data in the top-level key specified in the `key` field of `subject_ref`. The possible objects are as follows:
* `Estimate`
* `Workspace` (Project)
* `WorkspaceGroup` (Group)
* `Resource`
* `Story` (Task)
* `User`.'
schema:
type: string
responses:
'200':
description: The Custom Field Value 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_values:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomFieldValue'
external_references:
type: object
additionalProperties:
$ref: '#/components/schemas/ExternalReference'
custom_fields:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomField'
users:
type: object
additionalProperties:
$ref: '#/components/schemas/User'
custom_field_choices:
type: object
additionalProperties:
$ref: '#/components/schemas/CustomFieldChoice'
stories:
type: object
additionalProperties:
$ref: '#/components/schemas/Story'
workspaces:
type: object
additionalProperties:
$ref: '#/components/schemas/Workspace'
workspace_groups:
type: object
additionalProperties:
$ref: '#/components/schemas/WorkspaceGroup'
'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 Value
description: 'Updates an existing value for the specified custom field. Up to 100 values can be updated at one time.
This endpoint returns structured Custom Field Value 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_values` top-level JSON key.
Please see our Response Format section for more information.'
operationId: Update Custom Field Value
tags:
- Custom Field Values
parameters:
- in: path
name: id
required: true
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# Full source: https://raw.githubusercontent.com/api-evangelist/mavenlink/refs/heads/main/openapi/mavenlink-custom-field-values-api-openapi.yml