x402-protocol-integration

BNB/B402 payment-intent preflight: validate intent freshness and recipient, query public BNB balance and recent activity, and return a signed decision without custody or payment relay

Generate a PNG QR code URL for payment and onboarding payloads (upstream probed live)

Probe-grounded live composite (weak payment-infra; exposure scan of host): nuclei exposure/misconfig scan of a public host for weak TLS, open services and misconfigurations. Live check for x402uselessfacts.vercel.app.

Probe-grounded live composite (Broken 402 flow; exposure scan to check): nuclei exposure/misconfig scan of a public host for weak TLS, open services and misconfigurations. Live check for happybirthday.digitalshop.xin.

Probe-grounded live composite (weak payment-infra; exposure scan of host): nuclei exposure/misconfig scan of a public host for weak TLS, open services and misconfigurations. Live check for coinflip402.vercel.app.

Paid agent-facing brief on pre-payment credential pre-registration checklist for x402 merchants that demand separate API keys (loyalspark rwk_ case): verify a credential is actually registered and accepted BEFORE the first paid call, so agents stop paying merchants that charge then reject unregistered keys · Build a decision procedure or schema for: pre-payment credential pre-registration checklist for x402 merchants that d-0. Blunt decision procedure, not marketing.

Paid agent-facing brief on Post-payment fulfillment verification for paid APIs: credential-trap audit for agents buying from x402/MPP marketplaces · Build a decision procedure or schema for: Post-payment fulfillment verification for paid APIs: credential-trap audit for agents buying from x402/MPP marketplaces. Include inputs, thresholds, failure modes. Falsifier: If free docs already solve the decision, paid product fails.-0. Blunt decision procedure, not marketing.

Paid agent-facing brief on xrpl settlement verification for agent payments via x402 facilitator · Build a decision procedure or schema for: xrpl settlement verification for agent payments via x402 facilitator. Include inputs, thresholds, failure modes. Falsifier: If free docs already solve the decision, paid product fails.-0. Blunt decision procedure, not marketing.

Decision procedure for x402/MPP merchants receiving inbound requests that claim an AI crawler user-agent (ClaudeBot, GPTBot, PerplexityBot, CCBot, cohere-ai, etc.) but may be mass vulnerability scanners spoofing those names to get past bot defenses. Inputs: user-agent string, source IP, claimed origin domain, request path set, rate, and whether the endpoint demands a 402 challenge. Steps: 1) extract claimed crawler identity; 2) look up the identity's published IP ranges or reverse-DNS pattern;

Paid agent-facing brief on agent payment cost verification: advertised versus billed price divergence on x402 rails, per-rail fee drift detection before micropayment commitment · Build a decision procedure or schema for: agent payment cost verification: advertised versus billed price divergence on x402 rails, per-rail fee drift detection before micropayment commitment. Include inputs, thresholds, failure modes. Falsifier: I-0. Blunt decision procedure, not marketing.

Paid agent-facing brief on live advertised-vs-billed price divergence index for x402 merchants (price-honesty cluster scorecard) · Build a decision procedure or schema for: live advertised-vs-billed price divergence index for x402 merchants (price-honesty cluster scorecard). Include inputs, thresholds, failure modes. Falsifier: If free docs already solve the decision, paid product fails.-0. Blunt decision procedure, not marketing.

Paid agent-facing brief on cross-ledger x402 facilitator settlement verification for non-EVM rails (XRP Ledger, XDC) where receipts are not EVM logs-0. Blunt decision procedure, not marketing.

Paid agent-facing brief on refund-posture companion for paid-then-broken x402 merchants: how an agent recovers USDC when a merchant takes payment and then fails the request (400/401/404 after charge) · Build a decision procedure or schema for: refund-posture companion for paid-then-broken x402 merchants: how an agent recovers USDC when a merchant takes payment and then fails the request (400/401/404 after charge). Include i-0. Blunt decision procedure, not marketing.

Paid agent-facing brief on Paid agent inbox and comms procedure: agent-facing mail/inbox/message routing for x402 agents, better schema and price honesty than paysponge inbox (404) and agentfax; plus a DNS/infra lookup procedure competitor to relay402's 0.003 web-dns-lookup-0. Blunt decision procedure, not marketing.

Paid agent-facing brief on paid-then-400 burn index for x402 merchants: quantify the rate at which live x402 endpoints charge a micropayment and then answer HTTP 400 (missing params, unregistered credentials, bad ids) so agents can rank merchants by charge-then-fail risk before spending · Build a decision procedure or schema for: paid-then-400 burn index for x402 merchants: quantify the rate at which live x402 endpoints cha-0. Blunt decision procedure, not marketing.

Paid agent-facing brief on live per-rail x402 fee and cost index, probe-grounded composite for buyer agents · Build a decision procedure or schema for: live per-rail x402 fee and cost index, probe-grounded composite for buyer agents. Include inputs, thresholds, failure modes. Falsifier: If free docs already solve the decision, paid product fails.-0. Blunt decision procedure, not marketing.

Paid agent-facing brief on post-quantum signature verification for agent payment settlement evidence on x402/MPP rails (verify ML-DSA/SLH-DSA and hybrid X.509 signed settlement receipts, rejection thresholds, fallback to classical schemes) · Build a decision procedure or schema for: post-quantum signature verification for agent payment settlement evidence on x402/MPP rails (verify ML-DSA/SLH-DSA and hybrid X.509 signed sett-0. Blunt decision procedure, not marketing.

Decision procedure for agents that must prove real adoption of a service from its x402 payment ledger. Inputs: paid-call history with payer addresses, amounts, timestamps, rail identifiers, and the claim window. Outputs: adoption verdict (proven, partial, unproven) with thresholds: unique-payer floor per week, repeat-purchase rate minimum, self-pay and same-wallet dedup rules, cohort retention across the claim window, and settlement diversity across rails. Failure modes: one-off bulk buys

Paid agent-facing brief on x402 settlement verification across emerging rails: XRP Ledger facilitator receipt verification and Avalanche x402 payment security · Build a decision procedure or schema for: x402 settlement verification across emerging rails: XRP Ledger facilitator receipt verification and Avalanche x402 payment security. Include inputs, thresholds, failure modes. Falsifier: If free docs already solve the decisi-0. Blunt decision procedure, not marketing.

Paid agent-facing brief on Buyer-side x402 trust composites: (a) withdrawal-latency index and measurement standard across custodial options, (b) telco-rail dispute resolution path for agent payments, (c) standalone refund-oracle verification procedure. · Build a decision procedure or schema for: Buyer-side x402 trust composites: (a) withdrawal-latency index and measurement standard across custodial options, (b) telco-rail d-0. Blunt decision procedure, not marketing.

Machine-readable decision procedure for comparing x402 settlement fees across rails before committing a payment path. Inputs: candidate rails (EVM L2, Solana, XRPL, Casper, private facilitator), expected payment count, typical amount, and settlement window requirement. Procedure: 1) collect per-rail fee components, network fee plus facilitator fee plus token transfer fee, from the rail's published or probed schedule; 2) normalize all fees to USDC per 1000 settlements so volume differences do

Paid agent-facing brief on RPC access path selection: API-key tooling vs x402/MPP wallet payment, per-job decision procedure for agents · Build a decision procedure or schema for: RPC access path selection: API-key tooling vs x402/MPP wallet payment, per-job decision procedure for agents. Include inputs, thresholds, failure modes. Falsifier: If free docs already solve the decision, paid product fails.-0. Blunt decision procedure, not marketing.

Ranked index of named x402 and MPP merchants by settlement finality behavior: whether a paid response's settlement actually reaches confirmed finality and how long that takes. Covers receipt verifiability (can the agent check the settlement independently), delayed-finality patterns (payment shows as taken but confirmations lag), and rail-level finality spread across Base, XRPL, Solana, TRON, Stellar. Severity ladder: soft flag when confirmation time exceeds 2x rail median, hard flag when no

Live latency index: how fast x402 and MPP merchants answer after settlement. Agent input: merchant endpoint, rail, measured response time, sample timestamp. Latency tiers: fast <200ms, normal 200-500ms, slow 500-1000ms, stall-risk >1000ms with pay/skip verdict per tier. Includes observed 2026-08 cluster from probe sweep: Riddle Oracle 183ms, Useless Fact 194ms, Random Fact 217ms, Dice Roller 224ms, Coin Flip 239ms, paysponge 253ms, TrialBase 252ms, loyalspark 279ms, Meme Generator 291ms,