Skribble

Skribble Signature Observer API

Endpoints for managing observers on a signature request.

Documentation GitHub OpenAPI

Operations 4

POST /signature-requests/{SR_ID}/observers Add an observer to a signature request #

GET /signature-requests/{SR_ID}/observers List observers of a signature request #

GET /signature-requests/{SR_ID}/observers/{OBSERVER_ID} Get an observer of a signature request #

DELETE /signature-requests/{SR_ID}/observers/{OBSERVER_ID} Remove an observer from a signature request #

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Skribble Signature Observer API
  version: 3.1.0
  contact:
    name: Skribble Engineering
    url: https://skribble.com
    email: support@skribble.com
  license:
    name: Apache 2.0
    url: https://www.apache.org/licenses/LICENSE-2.0.html
  termsOfService: https://www.skribble.com/en-eu/terms-of-use/
  description: 'Operations tagged Signature Observer across 2 of this provider''s published API definitions: skribble-sign-v3-openapi.yml, skribble-sign-v3-openapi.yml. Each path carries the servers of the definition it was published in.'
servers:
- url: https://api.skribble.com/v3
  description: Production - Switzerland
- url: https://api.skribble.de/v3
  description: Production - Germany
security: []
tags:
- name: Signature Observer
  description: Endpoints for managing observers on a signature request.
paths:
  /signature-requests/{SR_ID}/observers:
    post:
      tags:
      - Signature Observer
      summary: Add an observer to a signature request
      description: 'Adds an observer to the specified signature request.


        Observers receive email notifications about signing progress and can view

        documents, but cannot sign them.


        Adding a **group** observer requires the group-observers feature to be enabled

        for the business. If it is not, the request fails with `403 Forbidden`

        (problem type `feature-not-enabled`).'
      operationId: addSignatureObserver
      security:
      - bearer: []
      parameters:
      - $ref: '#/components/parameters/SignatureIDPath'
      requestBody:
        description: Request body to create a SignatureObserver object
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateSignatureObserverRequest'
            examples:
              UserById:
                $ref: '#/components/examples/CreateUserByIdObserver'
              UserByMail:
                $ref: '#/components/examples/CreateUserByMailObserver'
              Group:
                $ref: '#/components/examples/CreateGroupObserver'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SignatureObserverResponse'
              examples:
                User:
                  $ref: '#/components/examples/SampleUserObserver'
                Group:
                  $ref: '#/components/examples/SampleGroupObserver'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/FeatureNotEnabled'
        '404':
          $ref: '#/components/responses/NotFound'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '500':
          $ref: '#/components/responses/ServerError'
        '503':
          $ref: '#/components/responses/ServiceUnavailable'
    get:
      tags:
      - Signature Observer
      summary: List observers of a signature request
      description: Returns all observers added to the `SignatureRequest` with the ID `SR_ID`.
      operationId: listSignatureObservers
      security:
      - bearer: []
      parameters:
      - $ref: '#/components/parameters/SignatureIDPath'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/SignatureObserverResponse'
              examples:
                Observers:
                  $ref: '#/components/examples/SampleObserverArray'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '500':
          $ref: '#/components/responses/ServerError'
        '503':
          $ref: '#/components/responses/ServiceUnavailable'
    servers:
    - url: https://api.skribble.com/v3
      description: Production - Switzerland
    - url: https://api.skribble.de/v3
      description: Production - Germany
  /signature-requests/{SR_ID}/observers/{OBSERVER_ID}:
    get:
      tags:
      - Signature Observer
      summary: Get an observer of a signature request
      description: 'Returns the observer identified by `OBSERVER_ID` from the `SignatureRequest`

        with the ID `SR_ID`.'
      operationId: getSignatureObserver
      security:
      - bearer: []
      parameters:
      - $ref: '#/components/parameters/SignatureIDPath'
      - $ref: '#/components/parameters/ObserverIDPath'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SignatureObserverResponse'
              examples:
                User:
                  $ref: '#/components/examples/SampleUserObserver'
                Group:
                  $ref: '#/components/examples/SampleGroupObserver'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '500':
          $ref: '#/components/responses/ServerError'
        '503':
          $ref: '#/components/responses/ServiceUnavailable'
    delete:
      tags:
      - Signature Observer
      summary: Remove an observer from a signature request
      description: 'Deletes the observer identified by `OBSERVER_ID` from the `SignatureRequest`

        with the ID `SR_ID`.'
      operationId: deleteSignatureObserver
      security:
      - bearer: []
      parameters:
      - $ref: '#/components/parameters/SignatureIDPath'
      - $ref: '#/components/parameters/ObserverIDPath'
      responses:
        '200':
          description: OK
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '500':
          $ref: '#/components/responses/ServerError'
        '503':
          $ref: '#/components/responses/ServiceUnavailable'
    servers:
    - url: https://api.skribble.com/v3
      description: Production - Switzerland
    - url: https://api.skribble.de/v3
      description: Production - Germany
components:
  schemas:
    ProblemResponse:
      title: Problem
      type: object
      description: 'Error response envelope returned for all 4xx and 5xx responses with a JSON body.

        Follows a Problem+JSON-style shape. The `key` field is optional and only present

        for errors that carry a machine-readable code.'
      required:
      - type
      - method
      - path
      - status
      - message
      properties:
        type:
          type: string
          format: uri
          description: 'URI identifying the problem category. The host of this URI depends on

            the environment the request was made against (e.g. `api.skribble.com`

            and `api.skribble.de` for the production regions; other environments

            use their respective hosts). Match on the path segment after `/problem/`

            rather than the full URI. Known values:


            - `https://api.skribble.com/problem/problem-with-message` — generic error with a message

            - `https://api.skribble.com/problem/entity-not-found` — requested resource does not exist

            - `https://api.skribble.com/problem/feature-not-enabled` — a required feature is not enabled for the business

            - `https://api.skribble.com/problem/constraint-violation` — request violates a domain constraint

            - `https://api.skribble.com/problem/parameterized` — parameterized error with details

            - `https://api.skribble.com/problem/limit-exceeded` — a usage limit was exceeded'
          example: https://api.skribble.com/problem/problem-with-message
        method:
          type: string
          description: HTTP method of the failing request.
          example: POST
        path:
          type: string
          description: Request URI of the failing request.
          example: /v2/signature-requests
        status:
          type: integer
          description: HTTP status code, mirroring the response status line.
          example: 400
        key:
          type: string
          description: 'Optional machine-readable error key. Present for a subset of errors that carry

            a stable code. Prefer matching on this field over parsing `message`, which is

            not part of the stable contract.


            Known keys, grouped by category:


            Authentication (`403`):


            - `error.auth.token_expired`: the access token has expired

            - `error.auth.token_invalid`: the access token is malformed or otherwise invalid

            - `error.auth.credentials_invalid`: the supplied credentials were rejected


            Rate limiting (`429`):


            - `error.rate_limit.exceeded`: a generic rate limit was exceeded

            - `error.rate_limit.reminder`: the per-signature-request reminder limit was exceeded


            File upload / attachment (`400`):


            - `file.attachment.unsupported`: the uploaded attachment type is not supported

            - `file.malware.detected`: malware was detected in the uploaded file


            PDF processing (`400`):


            - `file.pdf.general_error`: the PDF could not be loaded (corrupt or unreadable)

            - `file.pdf.encryption.unknown_password`: the PDF is encrypted with an unknown password

            - `file.pdf.encryption.no_changes_allowed`: the PDF''s signature permissions (DocMDP) do not allow the required changes

            - `file.pdf.encryption.unknown_permissions`: the PDF is encrypted with an unknown permissions type

            - `file.pdf.signature_verification.failed`: verification of an existing PDF signature failed


            Signature request (`400`):


            - `error.sr.last_document_cannot_be_removed`: the request would remove the only remaining document from the signature request; an SR must keep at least one document'
          example: file.attachment.unsupported
        message:
          type: string
          description: Human-readable error message.
          example: Validation failed for JSON object
    GroupObserverResponse:
      title: Group Observer Response
      type: object
      required:
      - id
      - type
      - invited_at
      - invited_by
      - group_info
      properties:
        id:
          type: string
          description: Unique observer identifier.
          example: ob_456
        type:
          type: string
          description: Observer type.
          const: GROUP
          example: GROUP
        invited_at:
          type: string
          format: date-time
          description: Timestamp when the observer was invited.
          example: '2026-02-02T12:34:56Z'
        invited_by:
          type: string
          description: Identifier of the user or API key that invited the observer.
          example: api_demo_example
        group_info:
          type: object
          description: Information about the group observer.
          required:
          - id
          - name
          properties:
            id:
              type: string
              description: Group ID.
              example: gr_456
            name:
              type: string
              description: Group name.
              example: Group 1
            version_id:
              type: string
              description: Group version identifier.
              example: gv_12
    UserObserverResponse:
      title: User Observer Response
      type: object
      required:
      - id
      - type
      - invited_at
      - invited_by
      - user_info
      properties:
        id:
          type: string
          description: Unique observer identifier.
          example: ob_123
        type:
          type: string
          description: Observer type.
          const: USER
          example: USER
        invited_at:
          type: string
          format: date-time
          description: Timestamp when the observer was invited.
          example: '2026-02-02T12:34:56Z'
        invited_by:
          type: string
          description: Identifier of the user or API key that invited the observer.
          example: api_demo_example
        user_info:
          type: object
          description: Information about the user observer.
          properties:
            id:
              type: string
              description: User ID.
              example: '123'
            email:
              type: string
              format: email
              description: User email address.
              example: you@example.info
    CreateSignatureObserverRequest:
      title: Signature Observer
      type: object
      description: 'Defines an observer target which can either be a USER or a GROUP.


        - For type USER, either email or user_id must be provided (but not both). When using email, a user will be automatically created if not present and returned.

        - For type GROUP, group_id must be provided and no user fields are allowed.'
      required:
      - type
      properties:
        type:
          type: string
          description: Type of observer target.
          enum:
          - USER
          - GROUP
          example: USER
      oneOf:
      - title: User Observer
        type: object
        required:
        - type
        properties:
          type:
            const: USER
        oneOf:
        - title: User by Email
          required:
          - email
          properties:
            email:
              type: string
              format: email
              description: Email address of the user.
              example: observer@example.info
        - title: User by ID
          required:
          - user_id
          properties:
            user_id:
              type: string
              description: Unique user identifier.
              example: usr_123
      - title: Group Observer
        type: object
        required:
        - type
        - group_id
        properties:
          type:
            const: GROUP
          group_id:
            type: string
            description: Unique group identifier.
            example: gr_456
    SignatureObserverResponse:
      description: 'Response object representing an observer that has been added to a signature request.


        Depending on the type, either user_info or group_info is present.'
      oneOf:
      - $ref: '#/components/schemas/UserObserverResponse'
      - $ref: '#/components/schemas/GroupObserverResponse'
      discriminator:
        propertyName: type
        mapping:
          USER: '#/components/schemas/UserObserverResponse'
          GROUP: '#/components/schemas/GroupObserverResponse'
  examples:
    SampleUserObserver:
      summary: User by ID or Mail
      value:
        id: ob_123
        type: USER
        invited_at: '2026-02-02T12:34:56Z'
        invited_by: admin@example.com
        user_info:
          id: usr_123
          email: observer@example.info
    SampleObserverArray:
      summary: List
      value:
      - id: ob_123
        type: USER
        invited_at: '2026-02-02T12:34:56Z'
        invited_by: admin@example.com
        user_info:
          id: usr_123
          email: observer@example.info
      - id: ob_124
        type: GROUP
        invited_at: '2026-02-02T12:40:00Z'
        invited_by: admin@example.com
        group_info:
          id: gr_456
          name: Group 1
          version_id: gv_12
    SampleGroupObserver:
      summary: Group
      value:
        id: ob_124
        type: GROUP
        invited_at: '2026-02-02T12:40:00Z'
        invited_by: admin@example.com
        group_info:
          id: gr_456
          name: Group 1
          version_id: gv_12
    CreateGroupObserver:
      summary: Group Observer
      value:
        type: GROUP
        group_id: gr_456
    CreateUserByIdObserver:
      summary: User by ID Observer
      value:
        type: USER
        user_id: '123'
    CreateUserByMailObserver:
      summary: User by Mail Observer
      value:
        type: USER
        email: observer@example.info
  responses:
    NotFound:
      description: Not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ProblemResponse'
          example:
            type: https://api.skribble.com/problem/entity-not-found
            method: GET
            path: /v2/signature-requests/00000000-0000-0000-0000-000000000000
            status: 404
            message: SignatureRequest not found
    Unauthorized:
      description: Unauthorized
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ProblemResponse'
          example:
            type: https://api.skribble.com/problem/problem-with-message
            method: GET
            path: /v2/signature-requests
            status: 401
            message: Unauthorized
    ServerError:
      description: Internal server error
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ProblemResponse'
          example:
            type: https://api.skribble.com/problem/problem-with-message
            method: POST
            path: /v2/signature-requests
            status: 500
            message: Internal server error
    BadRequest:
      description: Bad request
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ProblemResponse'
          example:
            type: https://api.skribble.com/problem/problem-with-message
            method: POST
            path: /v2/signature-requests
            status: 400
            message: Validation failed for JSON object
    FeatureNotEnabled:
      description: 'The requested operation depends on a feature that is not enabled for the

        business. The response carries the problem type

        `https://api.skribble.com/problem/feature-not-enabled`.'
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ProblemResponse'
          example:
            type: https://api.skribble.com/problem/feature-not-enabled
            method: POST
            path: /v2/signature-requests
            status: 403
            message: '''expires_at'' is not supported. Feature is not enabled.'
    TooManyRequests:
      description: Too many requests
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ProblemResponse'
          example:
            type: https://api.skribble.com/problem/problem-with-message
            method: POST
            path: /v2/signature-requests
            status: 429
            message: Too many requests
    ServiceUnavailable:
      description: Service unavailable
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ProblemResponse'
          example:
            type: https://api.skribble.com/problem/problem-with-message
            method: POST
            path: /v2/signature-requests
            status: 503
            message: Service unavailable
  parameters:
    SignatureIDPath:
      name: SR_ID
      in: path
      description: Unique ID received when creating the Signature Request object
      required: true
      schema:
        type: string
        format: uuid
      example: cccccccc-4a6a-a958-a42e-6ea4172a378b
    ObserverIDPath:
      name: OBSERVER_ID
      in: path
      description: Unique ID returned when the Signature Observer is created.
      required: true
      schema:
        type: string
      example: ob_123
  securitySchemes:
    bearer:
      type: http
      scheme: bearer
      bearerFormat: JWT
x-refined-from:
- skribble-sign-v3-openapi.yml
- skribble-sign-v3-openapi.yml