Live API for AI agents

Test Stripe's HTTP 402 rails.
$1.

12 API endpoints. Real payments. Full transparency. Built for AI agents.

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How it works

Three steps. No SDK. No setup ceremony.

1. Pay

Buy credits with Stripe. $1 buys 5 calls. Test card works in dev.

2. Get a key

You receive an ap_live_... API key on the success page. Save it once.

3. Call any endpoint

Bearer auth, JSON in, JSON or binary out. 1 credit per success.

Pricing

Pay-per-call, no subscriptions. Credits never expire.

$1
5 credits

Just enough to feel it.

Most popular
$5
30 credits

Best value for testing.

$20
150 credits

Power user.

12 ready-to-use endpoints

Each one costs 1 credit. No usage limits beyond your balance.

/qr-code

Generate QR codes from text

/og-image

Create social media OG images

/screenshot

Capture website screenshots

/pdf-from-url

Convert URLs to PDF

/word-count

Count words and reading time

/extract-metadata

Extract page meta tags

/extract-emails

Find emails on a page

/website-tech

Detect frameworks & CMS

/whois

Domain registration data

/domain-check

Check domain availability

/youtube-transcript

Get YouTube transcripts

/summarize

AI-powered summarization

Try it in 30 seconds

One key. One header. One endpoint. Pick your language.

# Buy credits at 402s.shop, then call any endpoint:

curl -X POST https://402s.shop/api/v1/qr-code \
  -H "Authorization: Bearer ap_live_..." \
  -H "Content-Type: application/json" \
  -d '{"text":"https://402s.shop"}' \
  --output qr.png

Why HTTP 402?

HTTP 402 Payment Required has been in the spec since 1996. Stripe's new agent rails finally give it a real implementation. We expose it so your agents can pay programmatically — full WWW-Authenticate header, X-Credits-Remaining, the works.

HTTP/1.1 402 Payment Required
WWW-Authenticate: Bearer realm="402s.shop", charge="$1"
X-Credits-Remaining: 0

FAQ

When an API call needs payment, the server returns HTTP 402 Payment Required with a WWW-Authenticate header pointing to a top-up URL. Agents read the header, fund credits, and retry. Each successful call returns the remaining balance in X-Credits-Remaining so the agent can budget itself.