Webhooks

If you’re not looking to build on top of the API, you can use the no-code webapp at https://app.useinkless.com/

Overview

Webhooks allow your application to receive real-time notifications when important events occur in your e-sign workflow, such as when a document is signed or a finalized PDF is generated. By registering a webhook, you can automate downstream actions (e.g., send emails, update your CRM, etc.) whenever these events happen.

Registering a Webhook

To receive webhook notifications, you must first register your webhook endpoint using the /registerWebhook API.

Endpoint

POST /registerWebhook

Request Headers

x-api-key: (required) Your API key for authentication.

Request Body

{
  "user_id": "your-user-id",
  "url": "https://yourdomain.com/webhook-endpoint",
  "eventType": "document.signed", // or "document.finalized"
  "secret": "optional-secret-key"
}

user_id: Your user ID (provided when you sign up for API access).
url: The HTTPS endpoint that will receive webhook events.
eventType: The event to subscribe to. Supported values:
- document.signed — triggered when a recipient signs a document.
- document.finalized — triggered when the final, signed PDF is available.
secret (optional): If provided, webhook payloads will be signed so you can verify authenticity.

Example Request

curl -X POST https://api.useinkless.com/registerWebhook \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "user_id": "user-123",
    "url": "https://yourdomain.com/webhook",
    "eventType": "document.signed"
  }'

Response

{
  "message": "Webhook registered",
  "webhook": {
    "webhook_id": "abc123",
    "url": "https://yourdomain.com/webhook",
    "eventType": "document.signed"
  }
}

Supported Webhook Events

Event Name	Description
`document.signed`	Triggered when a recipient signs a document.
`document.finalized`	Triggered when the final signed PDF is available to owner.

Webhook Payloads

When your webhook is triggered, your endpoint will receive a POST request with a JSON payload. The structure depends on the event.

document.signed Event

{
  "event": "document.signed",
  "pdf_id": "pdf-123",
  "recipient": {
    "name": "Recipient Name",
    "email": "recipient@example.com",
    "recipientHash": "hash123"
  },
  "completed_fields": [
    // ... array of completed field objects
  ],
  "status": "signed"
}

event: The event type.
pdf_id: The unique identifier for the document.
recipient: The recipient who signed (name, email, and a unique hash).
completed_fields: Information about completed fields (see API reference for structure).
status: The current status of the document.

document.finalized Event

{
  "event": "document.finalized",
  "pdf_id": "pdf-123",
  "final_pdf_url": "https://s3.amazonaws.com/your-bucket/final_document.pdf"
}

event: The event type.
pdf_id: The unique identifier for the document.
final_pdf_url: A secure, time-limited URL to download the finalized PDF.

Authenticating Webhook Requests

If you provided a secret when registering your webhook, each webhook request will include a signature header (x-webhook-signature) that you can use to verify the authenticity of the payload. (See below for verification instructions.)

Handling Webhooks

Your endpoint should: Respond with HTTP 200 OK as soon as possible. Validate the payload signature if a secret is used. Process the event according to your business logic. Example Webhook Handler (Node.js/Express)

app.post('/webhook', express.json(), (req, res) => {
  const event = req.body.event;
  if (event === 'document.signed') {
    // Handle document signed
  } else if (event === 'document.finalized') {
    // Handle finalized PDF
  }
  res.status(200).send('OK');
});

Authentication

All API endpoints are authenticated using Bearer tokens or API keys. Email hello@useinkless.com to get started with your API key. If you need more details or want to see sample payloads for other events, please reach out to support.

Get Started

API Documentation

Endpoints

Overview

Registering a Webhook

Endpoint

Request Headers

Request Body

Supported Webhook Events

Webhook Payloads

document.signed Event

document.finalized Event

Authenticating Webhook Requests

Handling Webhooks

Authentication

​Overview

​Registering a Webhook

​Endpoint

​Request Headers

​Request Body

​Supported Webhook Events

​Webhook Payloads

​document.signed Event

​document.finalized Event

​Authenticating Webhook Requests

​Handling Webhooks

​Authentication

Overview

Registering a Webhook

Endpoint

Request Headers

Request Body

Supported Webhook Events

Webhook Payloads

document.signed Event

document.finalized Event

Authenticating Webhook Requests

Handling Webhooks

Authentication