Call before paying an unfamiliar x402 endpoint, or to pick between providers. $0.02, usually <1 s plus one probe: live unpaid probe (status, latency, TLS, PAYMENT-REQUIRED decoded and sanity-checked), seller reputation from indexed on-chain USDC payments to its Base payTo (24 h/7 d count, distinct payers, total and median USD, top-payer share), Bazaar listing and price, and a looks legit/caution/avoid verdict citing each fact. Errors: 400/503 JSON {error}, not charged.

Call before buying, swapping into or accepting any Base ERC-20, to learn if you can sell it back. $0.02, ~1-3 s, measured on-chain: honeypot test (simulated buy then sell via the deepest pool: sell ok? round-trip loss vs fees), per-pool transfer tax from real recent swap receipts, USD liquidity per pool (Uniswap v2/v3, Aerodrome, Slipstream), sell quotes, and an ok/caution/avoid verdict citing each fact. Errors: 400/503 JSON {error}, not charged.