Mavenlink Attachments API

openapi: 3.2.0
info:
  version: 1.0.0
  title: Kantata OX API Documentation Attachments 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: Attachments
  description: 'An Attachment is a file asset that is attached to another Kantata OX object. Depending on the type of object,

    the file is used or displayed in different ways. The objects that Attachments can be attached to are:

    Post and Expense.


    To create an Expense or Post with an Attachment, use the resulting attachment_id from the Attachment creation

    request in the parameters of the Expense or Post creation request.'
paths:
  /attachments:
    post:
      summary: Creating a new Attachment
      description: There are two different ways to upload file attachments.
      operationId: Create Attachment
      tags:
      - Attachments
      responses:
        '200':
          description: Attachment 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
                  attachments:
                    type: object
                    additionalProperties:
                      $ref: '#/components/schemas/Attachments__Base'
        '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:
                attachment:
                  type: object
                  properties:
                    type:
                      type: string
                      description: 'Indicates the type of Attachment within Kantata OX.  Allowed values are: receipt or post_attachment.

                        A receipt is attached to an Expense, and a post_attachment is attached to a Post.'
                    direct:
                      type: boolean
                      description: 'Whether or not this is a direct CDN upload.  If direct is set to true, the filename field is required.

                        If direct is set to false or is not present, the data field is required.'
                    data:
                      type: string
                      description: 'The multipart/form-data encoded file contents.  Only used if direct is not set to true.  Note that the

                        maximum allowed size for file data uploads is 10MB.  For larger files, use a direct CDN upload.'
                    filename:
                      type: string
                      description: The filename of the file to be uploaded.  Only used if direct is set to true.
                  required:
                  - type
        required: true
  /attachments/{id}:
    put:
      summary: Updating an existing Attachment
      description: 'This endpoint returns structured Attachment 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 `attachments` top-level JSON key.

        Please see our Response Format section for more information.'
      operationId: Update Attachment
      tags:
      - Attachments
      parameters:
      - in: path
        name: id
        required: true
        description: The ID of the Model.
        schema:
          type: integer
      responses:
        '200':
          description: Attachment 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
                  attachments:
                    type: object
                    additionalProperties:
                      $ref: '#/components/schemas/Attachments__Base'
        '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:
                attachment:
                  type: object
                  properties:
                    filename:
                      type: string
                      description: Used to rename an already existing attachment within Kantata OX.
        required: true
    delete:
      summary: Deleting an existing Attachment
      description: 'Destroys an attachment from its subject object.


        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 Attachment
      tags:
      - Attachments
      parameters:
      - in: path
        name: id
        required: true
        description: The ID of the Model.
        schema:
          type: integer
      responses:
        '204':
          description: Attachment 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'
  /attachments/{id}/sync:
    put:
      summary: Sync a created attachment
      description: 'Marks an upload as complete, and verifies its existence on the CDN.


        This endpoint returns structured Attachment 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 `attachments` top-level JSON key.

        Please see our Response Format section for more information.'
      operationId: Sync Attachment
      tags:
      - Attachments
      parameters:
      - in: path
        name: id
        required: true
        description: The ID of the Model.
        schema:
          type: integer
      responses:
        '200':
          description: Attachment 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
                  attachments:
                    type: object
                    additionalProperties:
                      $ref: '#/components/schemas/Attachments__Base'
        '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:
    Errors:
      type: object
      properties:
        errors:
          type: array
          items:
            $ref: '#/components/schemas/Error'
    Attachments__Base:
      title: Attachment
      description: 'Attachments are files that accompany other resources provided by the Kantata OX API.  Expenses can have an

        attachment (tracked as a receipt).  Posts can also have attachments, which are displayed along with the post

        in the activity feed or in task tracker.'
      type: object
      properties:
        created_at:
          type: string
          format: date-time
        creator_name:
          type: string
          description: 'The user who originally uploaded the attachment.

            Visible when the attachment belongs to a post.'
        deletable:
          type: boolean
          description: 'Whether the current user can delete the attachment.

            Visible when the attachment belongs to a post.'
        deleted_at:
          type: string
          format: date-time
        filename:
          type: string
          description: The original filename of the attachment when it was uploaded.
        filesize:
          type: integer
          format: int32
          description: The size of the attachment, in bytes.
        previewable:
          type: boolean
          description: Whether the attachment is a previewable thumbnailed image.
        updated_at:
          type: string
          format: date-time
        url:
          type: string
          description: The url from which to download the attachment from the CDN.
        view_in_new_tab:
          type: boolean
          description: Whether the attachment is a filetype that should be viewed in a new tab; usually PDFs.
    Error:
      type: object
      properties:
        type:
          type: string
        message:
          type: string
  securitySchemes:
    BearerToken:
      type: apiKey
      name: Bearer
      in: header
    OauthSecurity:
      type: oauth2
      flows:
        authorizationCode:
          scopes: {}
          authorizationUrl: https://app.mavenlink.com/oauth/authorize
          tokenUrl: https://app.mavenlink.com/oauth/token
x-tagGroups:
- name: '# Subscribed Events'
  tags:
  - Event Types
  - Events
- name: Account Locations
  tags:
  - Account Locations
- name: Account Settings & Members
  tags:
  - Access Group Memberships
  - Account Colors
  - Account Invitations
  - Account Memberships
  - Backup Approver Associations
  - Billable Utilizations
  - Cost Rates
  - Custom Branding
  - Organization Memberships
  - Organizations
  - Roles
  - Skill Categories
  - Skill Memberships
  - Skills
  - Task Status Sets
  - Task Statuses
  - User Group Memberships
  - Users
- name: Currencies
  tags:
  - Currencies
- name: Custom Fields
  tags:
  - Custom Field Choices
  - Custom Field Sets
  - Custom Field Values
  - Custom Fields
- name: Data Exporter
  tags:
  - Data Export Schema
  - Data Exports
- name: Estimates
  tags:
  - Estimate Scenario Resource Allocations
  - Estimate Scenario Resources
  - Estimate Scenarios
  - Estimates
- name: Expense Budgets
  tags:
  - Expense Budgets
- name: Expense Tracking
  tags:
  - Attachments
  - Expense Categories
  - Expense Report Submissions
  - Expenses
  - Vendors
- name: External References
  tags:
  - External References
- name: Financials
  tags:
  - Billing Milestones
  - Revenue Recognition Methods
- name: Foreign Exchange
  tags:
  - Exchange Tables
- name: Insights & Analytics
  tags:
  - Insights Access Group Memberships
  - Insights Dynamic Dashboards
  - Insights Report Exports
  - Insights Reports
- name: Invoices
  tags:
  - Client Invoice Defaults
  - External Payments
  - Invoices
  - Workspace Invoice Preferences
- name: Personal Settings
  tags:
  - Users
- name: Posts & Replies
  tags:
  - Attachments
  - Posts
  - User File Associations
- name: Project Snapshots
  tags:
  - Project Snapshots
- name: Project Templates
  tags:
  - Project Template Additional Tabs
  - Project Template Assignments
  - Project Template Expense Budgets
  - Project Templates
- name: Projects
  tags:
  - Participations
  - Project Accounting Records
  - Status Reports
  - Workspace Allocations
  - Workspace Baselines
  - Workspace Groups
  - Workspace Invoice Preferences
  - Workspace Resource Skills
  - Workspace Resources
  - Workspace Status Changes
  - Workspace Task Status Sets
  - Workspaces
- name: Rate Cards
  tags:
  - Activations
  - Rate Card Role (Rate for a Role)
  - Rate Card Set Version (Effective version by Date)
  - Rate Card Sets (Group of Rate Cards)
  - Rate Card Table Rows
  - Rate Card Versions
  - Rate Cards (Multiple Currencies)
- name: Recommendations
  tags:
  - Recommendations
- name: Resource Requests
  tags:
  - Resource Requests
- name: Scheduling
  tags:
  - Holiday Calendar Associations
  - Holiday Calendar Memberships
  - Holiday Calendars
  - Holidays
  - Time Off Entries
  - Workweek Memberships
  - Workweeks
- name: Surveys (Legacy)
  tags:
  - Survey Answers (Legacy)
  - Survey Questions (Legacy)
  - Survey Templates (Legacy)
  - Surveys Responses (Legacy)
- name: Tasks
  tags:
  - Assignments
  - Daily Scheduled Hours (Story Allocation Days)
  - Followers
  - Stories
  - Story Dependencies
  - Story State Changes
  - Story Tasks
- name: Time Tracking
  tags:
  - Line Item Locks
  - Time Entries
  - Timesheet Approvals
  - Timesheet Cancellations
  - Timesheet Rejections
  - Timesheet Submissions