prompt-guard
Drop-in middleware for Claude & GPT apps

Stop prompt injection & data leaks in one call.

prompt-guard inspects every user message and model output, blocks injection attempts and jailbreaks, and redacts PII before it reaches the LLM. Free tier covers 5,000 requests a month.

npm i @prompt-guard/core

Try to break my agent

Send it an attack. Watch it get blocked — and any PII redacted — in real time.

Live, running the same @prompt-guard/core engine the API uses. Public demo is rate-limited.

Blocks prompt injection

Instruction overrides, DAN-style jailbreaks, system-prompt exfiltration, delimiter injection, tool hijacking — caught by a curated library of real attack patterns, not a brittle regex list.

Redacts PII before the model sees it

Emails, phone numbers, Luhn-checked cards, SSNs, IPs, and provider API keys are replaced with typed placeholders. Your users' secrets never hit the LLM or your logs.

One wrapper call

guard(message) returns a safe/unsafe verdict plus sanitized text in under a millisecond. Drop it in front of any Claude/GPT call. No model tokens, no added latency, no COGS.

A real jailbreak library, updated weekly

Anyone can ship a list of bad words. prompt-guard maintains a versioned library of attack patterns observed in the wild across 8 categories — instruction override, role jailbreaks, system-prompt exfiltration, delimiter injection, data exfiltration, encoding evasion, refusal suppression, and tool hijacking.

Browse the pattern library →

Simple, usage-based pricing

Start free. Upgrade when you ship.

USD $INR ₹

Free

Free
5,000 requests / mo
  • Injection + jailbreak detection
  • PII detection & redaction
  • Weekly pattern-library updates
  • Community support
Start free
Most popular

Pro

$29/mo
250,000 requests / mo
  • Everything in Free
  • Blocked-attempts dashboard
  • Output (model-response) scanning
  • Email support
  • 99.9% uptime
Upgrade to Pro

Scale

$99/mo
2,000,000 requests / mo
  • Everything in Pro
  • Custom policies & allow-lists
  • Priority pattern requests
  • SLA + Slack support
  • GST invoicing
Talk to us

Prices exclusive of GST. Razorpay (UPI/cards/netbanking) for India · Stripe for global. Cancel anytime.

Ship your LLM app without the 3am incident

Add one line. Block the attack you haven't thought of yet.