API Documentation

Welcome to the X0 Start API documentation. Our platform provides powerful tools to help you validate your business ideas through email subscription, feedback collection, and AI-powered chat.

For Subscribers

Already have an account? Visit your site settings page to get your personalized API token and site-specific setup instructions with live verification.

Getting Started

X0 Start offers two main ways to integrate with your website:

Widget Integration

Add our JavaScript widget to your site for instant access to email subscription forms, feedback widgets, and AI chatbot with minimal code.

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REST API

Build custom integrations using our RESTful API endpoints for complete control over data collection and user interactions.

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AI Integration

Build for AI Agents

X0 Start is built to be AI-friendly. We provide machine-readable specifications that allow AI agents to automatically discover and integrate with your site's API.

OpenAPI Spec llms.txt

Authentication

All API requests require authentication using a site-specific API token. This token is provided when you create a site in your X0 Start account.

Authentication Methods

1. HTTP Header (Recommended for API calls)

X-Site-Token: your_api_token_here

2. Meta Tag (For widget verification)

<meta name="x0-site-verification" content="your_api_token_here" />

3. Script URL Parameter (For static sites)

<script src="https://www.x0start.com/widget.js?token=your_api_token_here"></script>

Security Note: Keep your API token secure. While it's safe to use in client-side code for widget integration, avoid exposing it unnecessarily in public repositories.

Widget Integration

Our widget provides pre-built UI components that you can easily add to your website. It includes email subscription forms, feedback widgets, and an AI-powered chatbot.

JavaScript API

Load the widget script and use the global DomainWidget object to programmatically render components.

Step 1: Add the Script

<!-- Add to your HTML head or body -->
<meta name="x0-site-verification" content="YOUR_API_TOKEN" />
<script src="https://www.x0start.com/widget.js" async defer></script>

Step 2: Render Widgets

// Email Subscription Form
DomainWidget.renderEmailCapture('email-container', {
  title: 'Join Our Waitlist',
  description: 'Be the first to know when we launch!',
  buttonText: 'Sign Up',
  includeName: true
});

// Feedback Form
DomainWidget.renderFeedbackForm('feedback-container', {
  title: 'Share Your Thoughts',
  description: 'We value your feedback!'
});

// Chatbot (Inline)
DomainWidget.renderChatbot('chatbot-container', {
  inline: true,
  welcomeMessage: 'Hi! How can I help you today?'
});

// Chatbot (Floating Button)
DomainWidget.renderChatbot('chatbot-floating', {
  inline: false,
  defaultOpen: false
});

HTML Attributes

For a simpler setup, use HTML data attributes. The widget will automatically detect and render these elements.

<!-- Email Subscription -->
<div data-domain-widget="email-capture"
     data-title="Join Our Waitlist"
     data-description="Be the first to know!"
     data-button-text="Sign Up"
     data-include-name="true"></div>

<!-- Feedback Form -->
<div data-domain-widget="feedback-form"
     data-title="Share Your Thoughts"></div>

<!-- Floating Chatbot -->
<div data-domain-widget="chatbot"
     data-default-open="false"></div>

Widget Customization Options

Option	Type	Default	Description
`theme` Optional	String	'light'	Color scheme: 'light' or 'dark'

Option	Type	Default	Description
`title` Optional	String	'Join Our Waitlist'	Main title
`description` Optional	String	null	Description text
`includeName` Optional	Boolean	false	Show name field
`nameRequired` Optional	Boolean	false	Make name required
`buttonText` Optional	String	'Subscribe'	Button text
`successMessage` Optional	String	'Thanks!'	Success message
`type` Optional	String	null	Category/Tag for the subscription
`enableOptions` Optional	Boolean	false	Enable selection options
`options` Optional	Array	[]	List of options for selection
`multipleSelection` Optional	Boolean	false	Allow multiple option selection

Option	Type	Default	Description
`title` Optional	String	'Have Feedback?'	Main title
`description` Optional	String	'We'd love to hear'	Description
`buttonText` Optional	String	'Send Feedback'	Button text
`successMessage` Optional	String	'Thank you!'	Success message
`type` Optional	String	null	Feedback category (e.g., "bug", "feature")
`options` Optional	Object/JSON	null	Additional metadata fields

Option	Type	Default	Description
`title` Optional	String	'Chat with us'	Header title
`inline` Optional	Boolean	false	Inline vs floating
`defaultOpen` Optional	Boolean	false	Open by default
`welcomeMessage` Optional	String	'Hi there!'	Initial message

Option	Type	Default	Description
`title` Optional	String	null	Main title of the widget
`description` Optional	String	null	Text displayed below the title
`includeRating` Optional	Boolean	true	Show interactive 5-star rating input (defaults to 5 stars if false)
`reviewPlaceholder` Optional	String	'Share your experience...'	Placeholder for review textarea (500 char limit with counter)
`buttonText` Optional	String	'Submit Review'	Text for the submission button
`successMessage` Optional	String	'Thank you for your review!'	Message shown on successful submission
`thankYouSubtitle` Optional	String	'Your feedback is important to us!'	Subtitle shown in thank you banner after submission

Option	Type	Default	Description
`title` Optional	String	null	Main title of the widget
`displayMode` Optional	String	'carousel'	Display mode: 'carousel' (slideshow), 'grid' (responsive grid), or 'list' (vertical stack)
`showRating` Optional	Boolean	true	Display star ratings for each review
`showPosition` Optional	Boolean	true	Display reviewer position
`showCompany` Optional	Boolean	true	Display reviewer company
`showWebsite` Optional	Boolean	true	Display reviewer website link with favicon
`showFavicon` Optional	Boolean	true	Display website favicon next to website link
`autoRotate` Optional	Boolean	true	Auto-rotate reviews in carousel mode (pauses on hover)
`rotateInterval` Optional	Number	5000	Milliseconds between auto-rotation (carousel mode only)
`maxReviews` Optional	Number	20	Maximum number of reviews to fetch and display
`showOnlyFeatured` Optional	Boolean	false	Only show reviews marked as featured

REST API

Use our REST API for custom integrations. All endpoints require the X-Site-Token header.

Base URL: https://api.x0start.com

POST /api/v1/subscribe

Capture email addresses for waitlists, newsletters, or early access programs.

Headers

Content-Type: application/json
X-Site-Token: YOUR_API_TOKEN

Request Body

{
  "email": "[email protected]",
  "name": "John Doe",
  "type": "waitlist",
  "options": {
    "selected": ["Feature A"],
    "custom": "Additional info"
  }
}

cURL Example

curl -X POST https://api.x0start.com/api/v1/subscribe \
  -H "Content-Type: application/json" \
  -H "X-Site-Token: YOUR_API_TOKEN" \
  -d '{"email": "[email protected]", "type": "waitlist"}'

POST /api/v1/feedback

Collect user feedback and suggestions.

Request Body

{
  "feedback": "This is great!",
  "name": "Jane Doe",
  "email": "[email protected]",
  "type": "general",
  "options": {
    "category": "suggestion",
    "priority": "high"
  }
}

Request Parameters

Parameter	Type	Required	Description
`feedback`	String	Yes	The main content of the feedback or inquiry.
`name`	String	No	Name of the person submitting the feedback.
`email`	String	No	Contact email address.
`type`	String	No	Category classification (e.g., 'service_inquiry', 'bug', 'feature').
`options`	Object	No	Additional metadata or structured key-value pairs.

POST /api/v1/chat

Send messages to the AI chatbot and receive responses.

Request Body

{
  "message": "What features do you offer?",
  "sessionId": "unique-session-id",
  "endUserId": "user-123",
  "domain": "example.com"
}

cURL Example

curl -X POST https://api.x0start.com/api/v1/chat \
  -H "Content-Type: application/json" \
  -H "X-Site-Token: YOUR_API_TOKEN" \
  -d '{"message": "Hello!", "sessionId": "session-123"}'

POST /api/v1/reviews

Submit a customer review or testimonial.

Request Body

{
  "reviewer_name": "Jane Smith",
  "reviewer_email": "[email protected]",
  "reviewer_position": "CEO",
  "reviewer_company": "Acme Inc",
  "reviewer_website": "https://acme.com",
  "rating": 5,
  "review_text": "Excellent product! Highly recommend.",
  "invitation_token": "optional-token-if-from-invitation"
}

cURL Example

curl -X POST https://api.x0start.com/api/v1/reviews \
  -H "X-Site-Token: YOUR_SITE_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "reviewer_name": "Jane Smith",
    "reviewer_email": "[email protected]",
    "rating": 5,
    "review_text": "Excellent product!"
  }'

GET /api/v1/reviews

Get visible reviews for display on your website.

Request Body

Query Parameters:
- limit: Number of reviews to return (default: 20)
- featured_only: Only return featured reviews (true/false)

cURL Example

curl -X GET "https://api.x0start.com/api/v1/reviews?limit=10&featured_only=true" \
  -H "X-Site-Token: YOUR_SITE_TOKEN"

Widget Events

Listen to custom events emitted by the widgets to track user interactions.

Email Subscription Success

document.getElementById('email-container')
  .addEventListener('dw-email-capture-success', function(event) {
    console.log('Email captured:', event.detail.email);
  });

Feedback Submission Success

document.getElementById('feedback-container')
  .addEventListener('dw-feedback-success', function(event) {
    console.log('Feedback submitted:', event.detail);
  });

Review Submission Success

document.addEventListener('x0:review:success', (event) => {
  console.log('Review submitted:', event.detail);
  // Track in analytics, show custom thank you, etc.
});

Complete Examples

Landing Page with All Widgets

<!DOCTYPE html>
<html>
<head>
  <meta name="x0-site-verification" content="YOUR_API_TOKEN">
  <title>My Startup</title>
</head>
<body>
  <h1>Welcome to My Startup</h1>
  
  <div id="email-widget"></div>
  <div id="feedback-widget"></div>
  <div id="chatbot"></div>

  <script src="https://www.x0start.com/widget.js" async></script>
  <script>
    window.addEventListener('DOMContentLoaded', function() {
      if (typeof DomainWidget !== 'undefined') {
        initWidgets();
      } else {
        window.addEventListener('domain-widget-loaded', initWidgets);
      }
      
      function initWidgets() {
        DomainWidget.renderEmailCapture('email-widget', {
          title: 'Join Our Waitlist',
          includeName: true
        });
        
        DomainWidget.renderFeedbackForm('feedback-widget');
        DomainWidget.renderChatbot('chatbot', { inline: false });
      }
    });
  </script>
</body>
</html>

Need Help?

If you have questions or need assistance with integration, please don't hesitate to reach out.

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