Add signature annotation
A Signature Annotation serves as a designated placeholder within a document where the recipient is required to sign. You can include one or more signature annotations in a document. These annotations can be added alongside other types of annotations, such as text fields, date fields, and checkboxes. For further details, visit Annotation. Before adding the annotation, you need to define your signature in the Sign.Plus platform.
You will also need to add a document to the envelope and set a recipient using signing steps. You will get the recipient_id from the response of the signing steps and the document_id from the response of the document upload. Note that you can only add a signature annotation on a recipient that has a SIGNER role.
Coordinates of the annotation are passed in % of the page dimensions (from 0 to 100) counting from the top left corner
Add annotation
curl --request POST \
  --url https://restapi.sign.plus/v2/envelope/{envelope_id}/annotation \
  --header 'Authorization: Bearer <api-key>' \
  --header 'Content-Type: application/json' \
  --data '{
  "recipient_id": "<string>",
  "document_id": "<string>",
  "page": 1,
  "x": 50,
  "y": 20,
  "width": 20,
  "height": 60,
  "required": true,
  "type": "SIGNATURE",
  "signature": {
    "id": ""
  },
  "initials": null,
  "text": null,
  "datetime": null,
  "checkbox": null
}'
On success, the API will return the inserted annotation.

API Reference

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