curl --request PATCH \
  --url https://app.vumasign.com/api/v1/templates/{templateId}/fields/{fieldId} \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'If-Match: <if-match>' \
  --data '
{
  "data_key": "staff.full_name"
}
'

import requests

url = "https://app.vumasign.com/api/v1/templates/{templateId}/fields/{fieldId}"

payload = { "data_key": "staff.full_name" }
headers = {
    "If-Match": "<if-match>",
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.patch(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'PATCH',
  headers: {
    'If-Match': '<if-match>',
    Authorization: 'Bearer <token>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({data_key: 'staff.full_name'})
};

fetch('https://app.vumasign.com/api/v1/templates/{templateId}/fields/{fieldId}', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://app.vumasign.com/api/v1/templates/{templateId}/fields/{fieldId}"

	payload := strings.NewReader("{\n  \"data_key\": \"staff.full_name\"\n}")

	req, _ := http.NewRequest("PATCH", url, payload)

	req.Header.Add("If-Match", "<if-match>")
	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

{
  "warnings": [],
  "id": "01960000-0000-4000-8000-0000000007e1",
  "name": "Employment contract",
  "created_at": "2026-09-01T08:30:00.000Z",
  "documents": [
    {
      "id": "01960000-0000-4000-8000-00000000d0c5",
      "page_count": 1
    }
  ],
  "pages": [
    {
      "document_id": "01960000-0000-4000-8000-00000000d0c5",
      "page": 1,
      "width": 595.28,
      "height": 841.89,
      "rotation": 0
    }
  ],
  "roles": [
    {
      "name": "Employee",
      "routing_type": "sign",
      "kind": "party"
    }
  ],
  "subjects": [
    {
      "key": "employee",
      "label": "Employee"
    }
  ],
  "questions": [],
  "fields": [
    {
      "id": "01960000-0000-4000-8000-00000000f1e1",
      "type": "text",
      "label": "Full name",
      "required": true,
      "role": "Employee",
      "document_id": "01960000-0000-4000-8000-00000000d0c5",
      "page": 1,
      "subject": "employee",
      "data_key": "staff.full_name",
      "question_id": null,
      "options": null,
      "rect": {
        "x": 0.1007929,
        "y": 0.2107045,
        "w": 0.5288973,
        "h": 0.0213805
      },
      "context": {
        "label": "Full name",
        "row": null,
        "column": "Full name",
        "option": null,
        "section": "Employment contract",
        "nearby": [
          "<<text:Employee:Full name:subject(employee):key(full_name)>>",
          "Full name"
        ],
        "widget_name": null,
        "tooltip": null
      }
    }
  ],
  "coverage": {
    "prefillable": 1,
    "core": 0,
    "organisation": 1,
    "legacy": 0,
    "unnamed": 0,
    "questions": 0,
    "unnamed_groups": 0,
    "unnamed_options": 0,
    "collisions": 0
  }
}

{
  "error": {
    "code": "unauthenticated",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "unauthenticated",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "unauthenticated",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "unauthenticated",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "unauthenticated",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "unauthenticated",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "unauthenticated",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "unauthenticated",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "unauthenticated",
    "message": "<string>"
  }
}