How layers work
L1 Normalizer always
L2 Patterns always
L3 Classifier always
L4 LLM Judge ★ credits
L1 and L2 are always included on every scan (near-zero compute). L3 (transformer classifier, ~50ms) and L4 (LLM judge, ~300ms) consume monthly credits. When credits run out scans fall back to L1+L2. Credits don't roll over.
Built for AI agents
Agents discover plans and upgrade autonomously via the API — no human required.
Hit your scan limit and the 402 response tells your agent exactly what to do next.
# Agent receives HTTP 402 when free scans run out
# The response body contains machine-readable upgrade instructions:
{
"error": "free_tier_exhausted",
"x402": {
"accepts": [
{ "scheme": "signup", "description": "Developer plan: 1,000 scans/month, free" },
{ "scheme": "stripe-payment-link", "description": "Starter: 10,000 scans/month, $9/month" }
]
}
}
# Agent self-upgrades by POSTing to /v1/signup or /v1/billing/checkout
Frequently asked questions
Do I need a credit card to start?
No. The first 10 scans require no sign-up at all. After that, create a free Developer account with just an email address — no card needed until you upgrade to Starter or Pro.
What counts as a scan?
One call to POST /v1/scan counts as 1 scan. Each item in a POST /v1/scan/batch request also counts as 1 scan. Scans that return an error do not count toward your quota. Using a Layer 4 LLM judge credit also counts against your monthly credit allowance, not against your scan quota.
What are L4 judge credits and when are they used?
Layer 4 is an LLM-powered judge that resolves ambiguous cases — text that looks suspicious but didn't trigger Layers 1–3 conclusively. It's the most accurate layer but adds ~300ms and has a small per-call API cost. Credits are only consumed when the judge actually runs; clean text and clear-cut detections use no credits. When your credits run out, scans still run through L1–L3 for the rest of the month.
What happens when I hit my monthly limit?
The API returns HTTP 402 with a machine-readable response explaining how to upgrade. Your quota resets on the first of each month. You can upgrade at any time via POST /v1/billing/checkout.
Can I upgrade or cancel at any time?
Yes. Upgrades take effect immediately. Cancellations take effect at the end of your current billing period and your account reverts to the Developer plan. Manage everything via the customer portal at GET /v1/billing/portal.
How do AI agents pay autonomously?
When an agent exhausts its quota it receives a structured HTTP 402 response with an x402 field listing payment options. The agent can POST to /v1/signup for a free key, or surface the Stripe payment link to a human operator for paid plans. Once subscribed, the webhook upgrades the key automatically.
Is there a free trial for paid plans?
The Developer plan (1,000 scans/month free) acts as a permanent free tier. There is no time-limited trial — use Developer for as long as you need before upgrading.