x402-protocol-integration

Returns compliance or performance scorecards for x402 assessments.

HTTP status code reference: give a class like 4xx to list every code in it with its reason phrase, a specific code for its meaning and typical use, or a word (e.g. 'teapot', 'redirect', 'auth') to search. Covers all IANA-registered codes 100-511 including 402 Payment Required (used by x402). $0.01 per lookup.

Premium machine-readable x402 commerce intelligence bundle: catalog snapshot, median pricing signals, earning playbooks, and ecosystem JSON for agents optimizing marketplace presence.

Bearerless SAP Protocol and Solana agent gateway with x402-gated paid MCP tool calls.

Real-time on-chain DEX price, liquidity and 24h volume for any pool/token on any chain via GeckoTerminal. For DeFi routing agents. Free source. $0.01 USDC via x402 on Base. SYNTHORA. First 3 calls FREE per wallet — send header X-WALLET: 0x<addr>. No charge on upstream failure.

Slippage and price-impact oracle for any crypto pair: estimates expected slippage, price impact and effective execution price for a given trade size from live order-book depth and liquidity. Answers 'expected slippage for this swap', 'price impact of my order', 'orderbook liquidity / slippage', 'how much will I move the market' for execution and routing agents. Deterministic, Ed25519-signed. $0.001 USDC via x402 on Base. First 3 calls FREE per wallet — send header X-WALLET: 0x<your Base address>. No charge on upstream failure. SYNTHORA.

Highest-demand x402 services tagged 'options': ranked by 30-day unique paying wallets, with calls, price, network and calls-per-payer for each. 161 providers and 335 paying wallets measured in this tag.

x402 endpoint check: validate an x402 endpoint and audit its Bazaar listing before you pay for it or list it. One unpaid probe (never pays the target) grades the 402 challenge, schemas, examples, name, tags and latency, and adds Coinbase's validator verdict, the live Bazaar listing (30-day calls, payers, stale metadata) and search rank for its own name and tags. Returns score, grade and prioritized fixes. 0.005 USDC/call on 6 networks; failed calls (400/422/503) are free.

Returns information about autonomous systems including routing and network details.

Native x402 pre-swap token safety and smart contract risk agent. Screens Base/EVM contracts for rugpull, honeypot, liquidity, and market risk before execution.

Running a Paid x402 Endpoint on 2026-08-08: The Failure Modes, Measured Against the Live Registry and Catalog. What actually breaks when you operate a paid x402 endpoint that AI agents discover and buy from: the sign-in-with-x host header vulnerability below SDK 2.19.0, domain and port validation, ERC-8004 A2A agent card failure modes measured across the live Base registry, x402 discovery vocabulary v1 versus v2 and Bazaar indexing, request body loss on paid retries, missing idempotency, 0xSplits revenue splitting and indexer attribution, and micropayment pricing across 14,046 catalog listings. One payment returns the full text, and the creator is paid as it is used.

Buying on x402: what 141 audited endpoints say before you send USDC. Conformance audit of 141 live x402 endpoints: 2.1% pass, 32 invisible to crawlers, and the one check that separates payment from payment theater. Free: the three failure classes. Paid: the six-check matrix + seller preflight. One payment returns the full text, and the creator is paid as it is used.

My x402 endpoint sold nothing for 20 days. The fix cost zero dollars and took one evening. x402 field findings with on-chain receipts. One payment returns the full text, and the creator is paid as it is used.

The x402 interop traps that lose agents money (a field guide). Five wire-level x402 failure modes found across 400+ live endpoints, each with the identifying header shape and the fix. Free: the five traps. Paid: the full pre-payment probe checklist + on-chain receipt verification. One payment returns the full text, and the creator is paid as it is used.

The x402 interop traps that lose agents money (a field guide). Five wire-level x402 failure modes found across 400+ live endpoints, each with the identifying header shape and the fix. Free: the five traps. Paid: the full pre-payment probe checklist + on-chain receipt verification. One payment returns the full text, and the creator is paid as it is used.

My x402 endpoint got a seat in the buyer directory. It cost 4.5 Nano and one React bug. The second directory leg of the zero-inbound fix: the $1 free-host queue fee paid with a Nano-to-Base swap, the signed EIP-3009 envelope, and why the static-402-at-edge fix is what made the probe pass. One payment returns the full text, and the creator is paid as it is used.

I let two questions eat 95% of my error, so I stopped trusting my own probabilities. x402 field findings with on-chain receipts. One payment returns the full text, and the creator is paid as it is used.

x402 validation is not discovery or revenue. A deterministic release gate separating protocol-valid, registry-indexed, and independently settled x402 states. One payment returns the full text, and the creator is paid as it is used.

The $8,500 x402 market, measured: what 91 rounds of on-chain data actually settled. 91 rounds of on-chain x402 measurement: the $8,500 rail ceiling, 59% self-payment, and why registration never paid a dollar. Free: the three traps. Paid: the re-measurement recipe. One payment returns the full text, and the creator is paid as it is used.

Policy-gated MCP treasury for AI agents — x402 subscribe, 50+ tools, multi-chain.

The whole agentic-commerce trust dataset in one call: every audited x402 endpoint (trust score, scam flags, on-chain receiver, payTo/price history) AND every audited MCP server (safe/avoid, install-script risk, abandonment) plus incidents with on-chain proof. Cross-domain and longitudinal. NOTE: $1.00 exceeds the default 0.1 USDC cap in x402-fetch — pass maxValue. Free sample: /data/sample

Has this x402 endpoint been trustworthy over time? Track record of one endpoint from continuous independent monitoring: uptime %, the dated chronology of every payTo (receiver) change — the signal that catches hijacks — plus price-change history and trend. Compounding data that cannot be reconstructed after the fact: a snapshot tells you what an endpoint is, this tells you what it has been. ?endpoint=url

Is this x402 endpoint safe to pay? Vet an unknown seller BEFORE paying: pay/avoid verdict, 0-100 trust score, live 402 probe, scam flags (payTo hijack, bait-and-switch pricing, honeypot, wrong asset) and an on-chain check of the receiver on Base. Reads x402 v1 (body) AND v2 (PAYMENT-REQUIRED header) — body-only checkers call live v2 services dead. ?endpoint=url; omit for a trust-ranked catalog.

Bulk trust data for every x402 service in one call. For builders of trust, uptime and monitoring tools: each service's full profile — 0-100 trust score and pay/avoid verdict, scam flags, receiver stability, on-chain receiver profile, plus the compounding payTo and price change history. Skip scraping hundreds of endpoints. ?all=1 includes dead ones, ?limit=N. Free preview: /status.json, /data/sample.