Developer Guide

SignAndGo API
Integration Guide for Developers

Embed document signing directly into your application. Create envelopes, track status, and receive real-time webhooks -- all through a clean REST API.

|12 min read

API Overview

The SignAndGo API lets you programmatically create envelopes, upload documents, add recipients, track signing progress, and download completed PDFs. It is designed for developers building integrations with property management systems, CRMs, accounting software, and custom business applications.

RESTful

Standard REST endpoints with JSON responses. No proprietary SDKs required.

Secure

HTTPS only. Bearer token auth. HMAC-signed webhooks. Data in Sydney.

Real-Time

Webhooks notify your system instantly when signing events occur.

Authentication

All API requests require a valid API key passed as a Bearer token in the Authorization header.

Example Request
curl -X GET "https://signandgo-backend-308289583348.australia-southeast1.run.app/api/v1/envelopes" \
  -H "Authorization: Bearer sag_your_api_key_here" \
  -H "Content-Type: application/json"

Getting Your API Key

1

Log into your SignAndGo dashboard.

2

Navigate to Settings, then Developer API.

3

Click "Create API Key" and give it a descriptive name.

4

Select the required scopes: read, write, sign, admin.

5

Copy and securely store the generated key. It starts with sag_ and is only shown once.

API Key Scopes

ScopePermissions
readView envelopes, download signed documents
writeCreate envelopes, upload documents, add recipients
signTrigger signing flows, send invitations
adminManage webhooks, API key administration

Creating Envelopes

The primary integration point is creating envelopes -- uploading a document, specifying recipients, and optionally placing signature fields.

POST /api/v1/envelopes/external
curl -X POST "https://signandgo-backend-308289583348.australia-southeast1.run.app/api/v1/envelopes/external" \
  -H "Authorization: Bearer sag_your_api_key_here" \
  -F "file=@contract.pdf" \
  -F 'recipients=[{"name":"Jane Smith","email":"jane@example.com","role":"signer"}]' \
  -F "subject=Please sign this contract" \
  -F "message=Hi Jane, please review and sign the attached contract."

Response

{
  "envelope_id": "env_abc123",
  "status": "sent",
  "recipients": [
    {
      "name": "Jane Smith",
      "email": "jane@example.com",
      "signing_url": "https://www.signandgo.com.au/sign/tok_xyz789",
      "status": "sent"
    }
  ],
  "created_at": "2026-03-03T10:00:00Z"
}

If you do not place fields explicitly, SignAndGo enables free-form signing mode, where signers can click on the document to place their signature, initials, and date.

Webhooks

Receive real-time notifications when signing events occur.

Registering a Webhook

POST /api/v1/webhooks
{
  "url": "https://your-app.com/webhooks/signandgo",
  "events": ["signed", "completed", "declined"]
}

Webhook Events

  • envelope.sent -- Document sent to recipient
  • envelope.viewed -- Recipient opened document
  • envelope.signed -- Recipient signed
  • envelope.completed -- All signed
  • envelope.declined -- Recipient declined

Verifying Webhook Signatures

Every webhook payload includes an X-SignAndGo-Signature header containing an HMAC-SHA256 hash of the request body. Verify this against your webhook secret to ensure the payload is authentic.

import hmac, hashlib

def verify_signature(payload, signature, secret):
    expected = hmac.new(
        secret.encode(), payload, hashlib.sha256
    ).hexdigest()
    return hmac.compare_digest(expected, signature)

Integration Use Cases

Property Management Systems

Automatically generate and send tenancy agreements when a new lease is created. Receive a webhook when the tenant signs and update the lease status in your system.

CRM Integration

Send contracts from your CRM when a deal reaches "Won" stage. Track signing progress without leaving your CRM. Auto-attach the signed PDF to the deal record.

SaaS Onboarding

Embed signing into your customer onboarding flow. Generate service agreements dynamically, send for signing, and activate the account when the webhook confirms completion.

Inspection Platforms

Inspection tools like InspectAndGo use the API to send inspection reports for signing, then receive the signed document back via webhook for archival.

Start Building with the SignAndGo API

API access is available on the Business plan ($99/month) and above. Start with a free account to explore the platform.

Frequently Asked Questions

How do I get a SignAndGo API key?

Navigate to Settings then Developer API in your SignAndGo dashboard. Click 'Create API Key', select the required scopes (read, write, sign, admin), and copy the generated key. API keys start with 'sag_' and should be kept secret.

What authentication does the SignAndGo API use?

The API uses Bearer token authentication. Include your API key in the Authorization header: 'Authorization: Bearer sag_your_key_here'. All requests must be made over HTTPS.

Can I create envelopes via the API?

Yes. Use POST /api/v1/envelopes/external with a multipart form including the PDF document, recipient details, and optional field placements. The API returns an envelope ID and signing URLs for each recipient.

How do webhooks work in SignAndGo?

Register a webhook URL via the API or dashboard. SignAndGo will POST event payloads to your URL when documents are viewed, signed, declined, or completed. Payloads are HMAC-SHA256 signed with the X-SignAndGo-Signature header for verification.

Published 3 March 2026. API endpoints and responses may be updated -- always check the latest documentation.

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