Arthur Tags API

openapi: 3.1.0
info:
  title: Arthur Tags API
  version: 2.0.0
  description: Arthur Tags API - the tags surface of the Arthur API v2, the UK property management platform
    from Arthur Online (an Aareon company). Derived operation-for-operation from the provider's public
    Postman Documenter collection at https://developer.arthuronline.co.uk/. Every request is scoped to
    an Arthur entity via the mandatory X-EntityID header and authorised with an OAuth 2.0 Authorization
    Code access token.
  contact:
    name: Arthur Online API Support
    url: https://support.arthuronline.co.uk/
  termsOfService: https://www.arthuronline.co.uk/terms-and-conditions/
  x-derived-from: collections/arthur-online.postman_collection.json
  x-derived-by: API Evangelist enrichment pipeline
  x-derived-date: '2026-07-26'
servers:
- url: https://api.arthuronline.co.uk/v2
  description: Arthur API v2 production
security:
- arthurOAuth: []
tags:
- name: Tags
paths:
  /tags/{resource}:
    get:
      operationId: listTagsOnResource
      summary: List Tags On Resource
      tags:
      - Tags
      parameters:
      - name: resource
        in: path
        required: true
        description: Arthur resource.
        schema:
          type: string
      - $ref: '#/components/parameters/EntityId'
      - $ref: '#/components/parameters/Page'
      - $ref: '#/components/parameters/Limit'
      - $ref: '#/components/parameters/Sort'
      - $ref: '#/components/parameters/Direction'
      description: "This endpoint retrieves a list of tags related to the following resources:\n\nProperties\
        \ \n Units \n Tenancies \n Tasks \n Applicants \n Viewings"
      responses:
        '200':
          description: The request was completed successfully without errors.
          content:
            application/json:
              schema:
                type: object
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
    post:
      operationId: addTagOnResource
      summary: Add Tag On Resource
      tags:
      - Tags
      parameters:
      - name: resource
        in: path
        required: true
        description: Arthur resource.
        schema:
          type: string
      - $ref: '#/components/parameters/EntityId'
      - $ref: '#/components/parameters/Strict'
      description: "Use this endpoint to create a new tag record on a resource . The API will return the\
        \ saved data and a unique tag ID.\n\nTags can be added to resources such as tenancies, tasks,\
        \ units, applicants, viewings, and properties.\nIf field color not provided it will select a random\
        \ color.\n\nSupported Fields \n The following fields are supported for the request body\n\nField\
        \ \n Example \n Type \n Required? \n\nname \n All fixed \n String \n Yes \n\ncolor \n Blue \n\
        \ String \n No"
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                name:
                  type: string
                  example: All fixed
                color:
                  type: string
                  example: Blue
              required:
              - name
            example:
              name: Almost done
      responses:
        '200':
          description: The request was completed successfully without errors.
          content:
            application/json:
              schema:
                type: object
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
  /tags/{tag_id}:
    get:
      operationId: viewTag
      summary: View Tag
      tags:
      - Tags
      parameters:
      - name: tag_id
        in: path
        required: true
        description: Arthur tag id.
        schema:
          type: integer
      - $ref: '#/components/parameters/EntityId'
      description: 'This API endpoint retrieves the details of a single tag, identified by its unique 
        tag_id .


        Use this endpoint to view the specific details of a tag.'
      responses:
        '200':
          description: The request was completed successfully without errors.
          content:
            application/json:
              schema:
                type: object
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
    put:
      operationId: updateTag
      summary: Update Tag
      tags:
      - Tags
      parameters:
      - name: tag_id
        in: path
        required: true
        description: Arthur tag id.
        schema:
          type: integer
      - $ref: '#/components/parameters/EntityId'
      - $ref: '#/components/parameters/Strict'
      description: "This endpoint updates an existing tag using the same fields as the 'Add Tag' endpoint.\
        \ The API will return the updated data for the tag in the response.\n\nSupported Fields \n The\
        \ following fields are supported for the request body\n\nField \n Example \n Type \n Required?\
        \ \n\nname \n All fixed \n String \n No \n\ncolor \n Blue \n String \n No"
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                name:
                  type: string
                  example: All fixed
                color:
                  type: string
                  example: Blue
            example:
              name: Almost done updated
      responses:
        '200':
          description: The request was completed successfully without errors.
          content:
            application/json:
              schema:
                type: object
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
components:
  securitySchemes:
    arthurOAuth:
      type: oauth2
      description: OAuth 2.0 Authorization Code flow. Access tokens are valid for 14 days; refresh tokens
        for 21 days. Register an application in Arthur Settings > OAuth Applications to obtain a client_id
        and client_secret.
      flows:
        authorizationCode:
          authorizationUrl: https://auth.arthuronline.co.uk/oauth/authorize
          tokenUrl: https://auth.arthuronline.co.uk/oauth/token
          refreshUrl: https://auth.arthuronline.co.uk/oauth/token
          scopes: {}
  parameters:
    EntityId:
      name: X-EntityID
      in: header
      required: true
      description: The Arthur entity (account) the request is scoped to. Mandatory on every API call.
      schema:
        type: string
    Page:
      name: page
      in: query
      required: false
      description: Page number, between 1 and the total number of pages.
      schema:
        type: integer
        minimum: 1
    Limit:
      name: limit
      in: query
      required: false
      description: Items per page, between 1 and 100.
      schema:
        type: integer
        minimum: 1
        maximum: 100
    Sort:
      name: sort
      in: query
      required: false
      description: Field to sort the collection by.
      schema:
        type: string
    Direction:
      name: direction
      in: query
      required: false
      description: Sort direction.
      schema:
        type: string
        enum:
        - ASC
        - DESC
    Strict:
      name: strict
      in: query
      required: false
      description: When true, abort the request instead of auto-creating an unknown Simple type. POST
        and PUT only.
      schema:
        type: boolean
  schemas:
    Pagination:
      type: object
      description: Pagination block returned on every list response.
      properties:
        page:
          type: integer
        current:
          type: integer
        count:
          type: integer
        pageCount:
          type: integer
        limit:
          type: integer
    Error:
      type: object
      description: Arthur error envelope.
      properties:
        status:
          type: integer
        error:
          type: string
          description: Machine-readable error code, e.g. expired_token.
        message:
          type: string
  responses:
    BadRequest:
      description: The request was invalid or malformed.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    Unauthorized:
      description: Missing, invalid or expired access token.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error: expired_token
            message: This token has expired.
    NotFound:
      description: The request was sent to a location that does not exist in the API.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'