the402 endpoint detail

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launchcheck-x402.fly.dev v1 proposal-check

https://launchcheck-x402.fly.dev/v1/proposal-check

answers 402

Stress-test a product, feature, API, implementation, or business proposal before meaningful investment. ProposalCheck evaluates the core thesis, assumptions, differentiation, feasibility, economics, scope, dependencies, validation strategy, kill criteria, and recommended build sequence, then returns a structured green-light, revise, or rethink decision.

We sent a real POST request to this endpoint and it answered 402 with payment requirements we could parse.
Price
$2.00
Network
base
Pay to
0x87F929c4eCac1556a507cE6b92eF95c52B28DBa4
Spec dialect
v2 (declares x402Version 2)
Transport
PAYMENT-REQUIRED header
HTTP method
POST
Response latency
80 ms
Payment options
1 usable of 1
Last checked
2026-08-15T14:28:19.410Z (7d ago)
Category
other

Re-check it yourself:
curl "https://api.the402.dev/validate?url=https%3A%2F%2Flaunchcheck-x402.fly.dev%2Fv1%2Fproposal-check"