Pass/Fail before you waste budget on a doomed callGET /api/preflight · x402 API by promptqualityscore
Pass/Fail before you waste budget on a doomed call. Decide whether to make a paid LLM call before you make it. Preflight scores your prompt against an 8-dimension quality rubric (pass/fail at 28/80) and optionally pulls the target endpoint's on-chain trust signals — total payments, unique payers, last activity. Two-in-one circuit breaker for agents that don't want to waste budget on weak prompts or sketchy endpoints. (rev 2)
What does this x402 API do?
Pass/Fail before you waste budget on a doomed call. This is an x402-gated GET API resource from promptqualityscore. TOLL·402 confirmed a protocol-valid HTTP 402 quote on 2026-07-21. The listing records $0.05 USD-denominated per request on Base. No settled paid call has been verified.
- Published price
- $0.05 USD-denominated per request
- Networks
- Base
- Latest evidence
- TOLL·402 confirmed a protocol-valid HTTP 402 quote on 2026-07-21
- Resource ID
- da37486aca95bc8167a6694a
Start with a quote-only recipe. Payment signing stays in your project.
const response = await fetch("https://promptqualityscore.com/api/preflight", {
method: "GET",
});
console.log(response.status);
console.log(Object.fromEntries(response.headers));
console.log((await response.text()).slice(0, 1000));
// A valid 402 is a quote, not a completed paid call.This sends no payment. Inspect the 402 response before adding a wallet-enabled client.
- Live 402 quote confirmed
GET returned a protocol-valid 402 quote (402). No payment was made.
- Origin reachable
HEAD https://promptqualityscore.com/ returned 200.
- Observed in 402-index
Discovered through bazaar.
- Registry record checked
Registry health: healthy.
What evidence supports this listing?
Each record has an exact-route quote outcome. Unresolved templates and potentially mutating methods are labeled instead of being invoked without provider-specific test input. A quote is still separate from a settled paid call. Read the discovery and verification methodology →
Which networks and payment options does it accept?
The normalized listing price is $0.05 USD-denominated per request. Raw protocol requirements remain visible below for implementation and audit use.