SignNow

Access the SignNow API with managed OAuth authentication. Upload documents, send signature invites, manage templates, and automate e-signature workflows.

Quick Start

# Get current user info
python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/signnow/user')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Base URL

https://gateway.maton.ai/signnow/{resource}

The gateway proxies requests to api.signnow.com and automatically injects your OAuth token.

Authentication

All requests require the Maton API key in the Authorization header:

Authorization: Bearer $MATON_API_KEY

Environment Variable: Set your API key as MATON_API_KEY:

export MATON_API_KEY="YOUR_API_KEY"

Getting Your API Key

1. Sign in or create an account at maton.ai
2. Go to maton.ai/settings
3. Copy your API key

Connection Management

Manage your SignNow OAuth connections at https://ctrl.maton.ai.

List Connections

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://ctrl.maton.ai/connections?app=signnow&status=ACTIVE')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Create Connection

python <<'EOF'
import urllib.request, os, json
data = json.dumps({'app': 'signnow'}).encode()
req = urllib.request.Request('https://ctrl.maton.ai/connections', data=data, method='POST')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
req.add_header('Content-Type', 'application/json')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Get Connection

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://ctrl.maton.ai/connections/{connection_id}')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Response:

{
  "connection": {
    "connection_id": "5ff5474b-5f21-41ba-8bf3-afb33cce5a75",
    "status": "ACTIVE",
    "creation_time": "2026-02-08T20:47:23.019763Z",
    "last_updated_time": "2026-02-08T20:50:32.210896Z",
    "url": "https://connect.maton.ai/?session_token=...",
    "app": "signnow",
    "metadata": {}
  }
}

Open the returned url in a browser to complete OAuth authorization.

Delete Connection

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://ctrl.maton.ai/connections/{connection_id}', method='DELETE')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Specifying Connection

If you have multiple SignNow connections, specify which one to use with the Maton-Connection header:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/signnow/user')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
req.add_header('Maton-Connection', '5ff5474b-5f21-41ba-8bf3-afb33cce5a75')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

If omitted, the gateway uses the default (oldest) active connection.

API Reference

User Operations

Get Current User

GET /signnow/user

Response:

{
  "id": "59cce130e93a4e9488522ca67e3a6779f3e48a72",
  "first_name": "Chris",
  "last_name": "Kim",
  "active": "1",
  "verified": true,
  "emails": ["chris@example.com"],
  "primary_email": "chris@example.com",
  "document_count": 0,
  "subscriptions": [...],
  "teams": [...],
  "organization": {...}
}

Get User Documents

GET /signnow/user/documents

Response:

[
  {
    "id": "c63a7bc73f03449c987bf0feaa36e96212408352",
    "document_name": "Contract",
    "page_count": "3",
    "created": "1770598603",
    "updated": "1770598603",
    "original_filename": "contract.pdf",
    "owner": "chris@example.com",
    "template": false,
    "roles": [],
    "field_invites": [],
    "signatures": []
  }
]

Document Operations

Upload Document

Documents must be uploaded as multipart form data with a PDF file:

python <<'EOF'
import urllib.request, os, json

def encode_multipart_formdata(files):
    boundary = '----WebKitFormBoundary7MA4YWxkTrZu0gW'
    lines = []
    for (key, filename, content) in files:
        lines.append(f'--{boundary}'.encode())
        lines.append(f'Content-Disposition: form-data; name="{key}"; filename="{filename}"'.encode())
        lines.append(b'Content-Type: application/pdf')
        lines.append(b'')
        lines.append(content)
    lines.append(f'--{boundary}--'.encode())
    lines.append(b'')
    body = b'\r\n'.join(lines)
    content_type = f'multipart/form-data; boundary={boundary}'
    return content_type, body

with open('document.pdf', 'rb') as f:
    file_content = f.read()

content_type, body = encode_multipart_formdata([('file', 'document.pdf', file_content)])
req = urllib.request.Request('https://gateway.maton.ai/signnow/document', data=body, method='POST')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
req.add_header('Content-Type', content_type)
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Response:

{
  "id": "c63a7bc73f03449c987bf0feaa36e96212408352"
}

Get Document

GET /signnow/document/{document_id}

Response:

{
  "id": "c63a7bc73f03449c987bf0feaa36e96212408352",
  "document_name": "Contract",
  "page_count": "3",
  "created": "1770598603",
  "updated": "1770598603",
  "original_filename": "contract.pdf",
  "owner": "chris@example.com",
  "template": false,
  "roles": [],
  "viewer_roles": [],
  "attachments": [],
  "fields": [],
  "signatures": [],
  "texts": [],
  "checks": []
}

Update Document

PUT /signnow/document/{document_id}
Content-Type: application/json

{
  "document_name": "Updated Contract Name"
}

Response:

{
  "id": "c63a7bc73f03449c987bf0feaa36e96212408352",
  "signatures": [],
  "texts": [],
  "checks": []
}

Download Document

GET /signnow/document/{document_id}/download?type=collapsed

Returns the PDF file as binary data.

Query parameters:

• type - Download type: collapsed (flattened PDF), zip (all pages as images)

Get Document History

GET /signnow/document/{document_id}/historyfull

Response:

[
  {
    "unique_id": "c4eb89d84b2b407ba8ec1cf4d25b8b435bcef69d",
    "user_id": "59cce130e93a4e9488522ca67e3a6779f3e48a72",
    "document_id": "c63a7bc73f03449c987bf0feaa36e96212408352",
    "email": "chris@example.com",
    "created": 1770598603,
    "event": "created_document"
  }
]

Move Document to Folder

POST /signnow/document/{document_id}/move
Content-Type: application/json

{
  "folder_id": "5e2798bdd3d642c3aefebe333bb5b723d6db01a4"
}

Response:

{
  "result": "success"
}

Merge Documents

Combines multiple documents into a single PDF:

POST /signnow/document/merge
Content-Type: application/json

{
  "name": "Merged Document",
  "document_ids": ["doc_id_1", "doc_id_2"]
}

Returns the merged PDF as binary data.

Delete Document

DELETE /signnow/document/{document_id}

Response:

{
  "status": "success"
}

Template Operations

Create Template from Document

POST /signnow/template
Content-Type: application/json

{
  "document_id": "c63a7bc73f03449c987bf0feaa36e96212408352",
  "document_name": "Contract Template"
}

Response:

{
  "id": "47941baee4f74784bc1d37c25e88836fc38ed501"
}

Create Document from Template

POST /signnow/template/{template_id}/copy
Content-Type: application/json

{
  "document_name": "New Contract from Template"
}

Response:

{
  "id": "08f5f4a2cc1a4d6c8a986adbf90be2308807d4ae",
  "name": "New Contract from Template"
}

Signature Invite Operations

Send Freeform Invite

Send a document for signature:

POST /signnow/document/{document_id}/invite
Content-Type: application/json

{
  "to": "signer@example.com",
  "from": "sender@example.com"
}

Response:

{
  "result": "success",
  "id": "c38a57f08f2e48d98b5de52f75f7b1dd0a074c00",
  "callback_url": "none"
}

Note: Custom subject and message require a paid subscription plan.

Create Signing Link

Create an embeddable signing link (requires document fields):

POST /signnow/link
Content-Type: application/json

{
  "document_id": "c63a7bc73f03449c987bf0feaa36e96212408352"
}

Note: Document must have signature fields added before creating a signing link.

Folder Operations

Get All Folders

GET /signnow/folder

Response:

{
  "id": "2ea71a3a9d06470d8e5ec0df6122971f47db7706",
  "name": "Root",
  "system_folder": true,
  "folders": [
    {
      "id": "5e2798bdd3d642c3aefebe333bb5b723d6db01a4",
      "name": "Documents",
      "document_count": "5",
      "template_count": "2"
    },
    {
      "id": "fafdef6de6d947fc84627e4ddeed6987bfeee02d",
      "name": "Templates",
      "document_count": "0",
      "template_count": "3"
    },
    {
      "id": "6063688b1e724a25aa98befcc3f2cb7795be7da1",
      "name": "Trash Bin",
      "document_count": "0"
    }
  ],
  "total_documents": 0,
  "documents": []
}

Get Folder by ID

GET /signnow/folder/{folder_id}

Response:

{
  "id": "5e2798bdd3d642c3aefebe333bb5b723d6db01a4",
  "name": "Documents",
  "user_id": "59cce130e93a4e9488522ca67e3a6779f3e48a72",
  "parent_id": "2ea71a3a9d06470d8e5ec0df6122971f47db7706",
  "system_folder": true,
  "folders": [],
  "total_documents": 5,
  "documents": [...]
}

Webhook (Event Subscription) Operations

List Event Subscriptions

GET /signnow/event_subscription

Response:

{
  "subscriptions": [
    {
      "id": "b1d6700dfb0444ed9196e913b2515ae8d5f731a7",
      "event": "document.complete",
      "created": "1770598678",
      "callback_url": "https://example.com/webhook"
    }
  ]
}

Create Event Subscription

POST /signnow/event_subscription
Content-Type: application/json

{
  "event": "document.complete",
  "callback_url": "https://example.com/webhook"
}

Response:

{
  "id": "b1d6700dfb0444ed9196e913b2515ae8d5f731a7",
  "created": 1770598678
}

Available Events:

• document.create - Document created
• document.update - Document updated
• document.delete - Document deleted
• document.complete - Document signed by all parties
• invite.create - Invite sent
• invite.update - Invite updated

Delete Event Subscription

DELETE /signnow/event_subscription/{subscription_id}

Response:

{
  "id": "b1d6700dfb0444ed9196e913b2515ae8d5f731a7",
  "status": "deleted"
}

Code Examples

JavaScript

const response = await fetch(
  'https://gateway.maton.ai/signnow/user',
  {
    headers: {
      'Authorization': `Bearer ${process.env.MATON_API_KEY}`
    }
  }
);
const data = await response.json();

Python

import os
import requests

response = requests.get(
    'https://gateway.maton.ai/signnow/user',
    headers={'Authorization': f'Bearer {os.environ["MATON_API_KEY"]}'}
)
data = response.json()

Python (Upload Document)

import os
import requests

with open('document.pdf', 'rb') as f:
    response = requests.post(
        'https://gateway.maton.ai/signnow/document',
        headers={'Authorization': f'Bearer {os.environ["MATON_API_KEY"]}'},
        files={'file': ('document.pdf', f, 'application/pdf')}
    )
doc = response.json()
print(f"Uploaded document: {doc['id']}")

Python (Send Invite)

import os
import requests

doc_id = "c63a7bc73f03449c987bf0feaa36e96212408352"
response = requests.post(
    f'https://gateway.maton.ai/signnow/document/{doc_id}/invite',
    headers={
        'Authorization': f'Bearer {os.environ["MATON_API_KEY"]}',
        'Content-Type': 'application/json'
    },
    json={
        'to': 'signer@example.com',
        'from': 'sender@example.com'
    }
)
result = response.json()
print(f"Invite sent: {result['id']}")

Notes

• Documents must be in PDF format for upload
• Supported file types: PDF, DOC, DOCX, ODT, RTF, PNG, JPG
• System folders (Documents, Templates, Archive, Trash Bin) cannot be renamed or deleted
• Creating signing links requires documents to have signature fields
• Custom invite subject/message requires a paid subscription
• Rate limit in development mode: 500 requests/hour per application
• IMPORTANT: When piping curl output to jq or other commands, environment variables like $MATON_API_KEY may not expand correctly in some shell environments

Error Handling

SignNow errors include detailed messages:

{
  "errors": [
    {
      "code": 65578,
      "message": "Invalid file type."
    }
  ]
}

Troubleshooting: Invalid API Key

When you receive a "Invalid API key" error, ALWAYS follow these steps before concluding there is an issue:

1. Check that the MATON_API_KEY environment variable is set:

echo $MATON_API_KEY

1. Verify the API key is valid by listing connections:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://ctrl.maton.ai/connections')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Resources

• SignNow API Reference
• SignNow Developer Portal
• SignNow Postman Collection
• SignNow SDKs