JSON Guardian - Schema Enforcement API for LLM Outputs

The Problem We Solve

❌ Without JSON Guardian

AI returns string instead of JSON object
Missing required fields break your pipeline
Malformed JSON crashes production
Manual error handling eats dev time
Unpredictable LLM outputs cause outages

✅ With JSON Guardian

Auto-repair common syntax errors
Enforce schemas with smart defaults
Validate in under 10 milliseconds
Set it and forget it
Production-grade reliability

Dead Simple Integration

// Validate LLM output against your schema
const response = await fetch('https://api.jsonguardian.com/api/v1/validate', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'X-API-Key': 'your-api-key'
  },
  body: JSON.stringify({
    schema: yourSchema,
    data: llmOutput
  })
});

const { valid, parsed_data, errors } = await response.json();
// ✅ Validated, repaired, and ready to use!

Works with JavaScript, Python, Go, Rust, PHP, Ruby, and any language with HTTP.

Why Choose JSON Guardian?

⚡

Blazing Fast

Written in Rust. Sub-10ms latency. Handles 3,000+ requests per second.

🛠️

Smart Repairs

Automatically fixes trailing commas, missing brackets, unquoted keys, and more.

🔒

Secure & Private

We don't log or store your JSON data. Processed in-memory and discarded.

💰

Cost Effective

No LLM calls means pennies per million validations. Save 95%+ vs other solutions.

📊

Real-Time Metrics

Track usage, monitor performance, and get alerts via our dashboard.

🌍

Global Edge

Deployed worldwide for low-latency responses wherever your users are.

Simple, Transparent Pricing

Free

$0/mo

✓ 10,000 requests/month
✓ All core features
✓ Email support
✓ No credit card required
✓ Community support

Start Free

Starter

$9/mo

✓ 100,000 requests/month
✓ All features
✓ Priority email support
✓ 99.9% uptime SLA
✓ Usage analytics

Get Started

Pro

$29/mo

✓ 1,000,000 requests/month
✓ All features
✓ Priority support (24hr)
✓ 99.9% uptime SLA
✓ Advanced analytics

Scale Up

All prices in USD. Cancel anytime. 7-day money-back guarantee.

Frequently Asked Questions

Is my data safe? ▼

Absolutely. We don't log or store your JSON data. All requests are processed in-memory and immediately discarded. We only track usage counts for billing purposes. Your data never touches our database.

How fast is the API? ▼

JSON Guardian is built in Rust for maximum performance. Average response time is under 10ms, with p99 latency under 50ms even under heavy load. We handle 3,000+ requests per second per instance.

What if I need more requests? ▼

Contact us for custom enterprise plans with higher limits. We offer volume discounts for high-usage customers. Email support@jsonguardian.com to discuss your needs.

What about vendor lock-in? ▼

Our API uses standard REST conventions. If you ever need to switch, it's just changing a URL. We also provide data export for your usage history. No lock-in, no tricks.

Do you offer refunds? ▼

Yes! All paid plans come with a 7-day money-back guarantee. If you're not satisfied, just email us within 7 days of purchase for a full refund, no questions asked.