Live: https://x402-seller-pmlm.onrender.com · Agent guide: /llms.txt · OpenAPI: /openapi.json · Discovery: /.well-known/x402
No API key, no signup. AI agents pay per request in USDC on Base (eip155:8453), Polygon (eip155:137),
Arbitrum (eip155:42161), Solana mainnet (CDP facilitator) or Avalanche (eip155:43114) and Sei (eip155:1329)
(free PayAI facilitator) using the
x402 protocol, settled through the Coinbase CDP facilitator and listed in the CDP x402 Bazaar.
| Endpoint | Price | Use it when | Returns |
|---|
GET /report?q=<question> | $0.01 | You need a quick, cited answer or background on a topic | 1-3 sentence answer, key_points tied to source ids, sources[] (typically 1-5: Wikipedia first, plus Stack Overflow, GitHub, Crossref papers, official docs when they match; off-topic sources dropped) with URLs, dates and supporting quotes, confidence |
GET /read?url=<https url> | $0.005 | You have a URL and need its text for an LLM | title, description, publishedAt, clean markdown, wordCount, headings[], links[] |
GET /check?url=<x402 endpoint> | $0.005 | You are about to pay for or list an x402 API | readiness score, per-check results, fixes[] (one unpaid probe; never pays the target) |
GET /news?q=<keywords> | $0.005 | You need what happened on a topic in the last 1-7 days | articles[] (title, url, outlet, publishedAt, match score, partialMatch), outlets, provider status. Optional hours (1-168, default 72), limit (1-25). Headlines + links only |
GET /price?token=<symbol, 0x address or Solana mint> | $0.002 | You need a verifiable USD price + 24h change for a token | priceUsd, change24hPct + priceUsd24hAgo (EVM), confidence, poolSpreadPct, totalDepthUsd, pools[] with explorer links, block/slot. Optional chain (ethereum, base, arbitrum, polygon, solana) |
GET /solana-price?token=<symbol or mint> | $0.002 | You need a Solana token price (incl. pump.fun / PumpSwap tokens) | priceUsd, confidence, thinLiquidity, pools[] (Orca Whirlpool, Raydium CLMM, PumpSwap, pump.fun curve) with depth, poolSpreadPct, solUsd, slot |
GET /balance?address=<0x, name.eth or Solana address> | $0.003 | You need what a wallet holds and what it is worth | per-chain native + tokens[] (balance, price, USD) and totalUsd; EVM = Ethereum, Base, Arbitrum, Polygon in one call. Optional chain, tokens (extra contracts/mints) |
GET /tx?hash=<0x hash or Solana signature> | $0.003 | You need to know if a tx/payment landed and what it did | status, timestamp, confirmations, from/to, decoded method (flags x402 / EIP-3009 USDC payments), fee in USD, decoded tokenTransfers[] (EVM) or SOL/token balance changes (Solana). Optional chain |
GET /gas[?chain=] | $0.002 | You need current fees before sending a tx | base fee, slow/standard/fast priority fees, maxFeePerGas, USD cost of a transfer / ERC-20 transfer / swap per EVM chain, Solana priority fees, cheapestEvmForErc20Transfer |
Never charged for errors: 400 bad input, 422 nothing found / target unreachable, 503 unavailable.
The x402 middleware only settles a payment when the handler returns 2xx.
Call it
curl -i "https://x402-seller-pmlm.onrender.com/report?q=history+of+the+transistor"
import { wrapFetchWithPayment } from "@x402/fetch";
const res = await fetchWithPayment("https://x402-seller-pmlm.onrender.com/report?q=what+is+RAG");
console.log(await res.json());
Run it yourself
Node 22+, a CDP API key (https://portal.cdp.coinbase.com), and a Base receive address.
cp .env.example .env
npm ci && npm run dev
| Env | Default | Notes |
|---|
X402_ENV | development | production = Base, Polygon, Arbitrum, Solana (CDP) + Avalanche, Sei (PayAI); development = Base Sepolia + Solana Devnet |
X402_NETWORKS | per X402_ENV | Optional comma-separated CAIP-2 override, e.g. eip155:8453,eip155:137 (supported: 8453, 137, 42161, 43114, 1329, 84532, Solana mainnet/devnet). Same X402_PAY_TO on every EVM chain |
X402_SOLANA_PAY_TO | built-in public address | Solana receive address (public key only; the secret never lives in this repo) |
PAYAI_FACILITATOR_URL | https://facilitator.payai.network | Facilitator for Avalanche/Sei (free tier, no API key) |
X402_PAY_TO | — | Your EVM receive address (else CDP provisions one; needs CDP_WALLET_SECRET) |
REPORT_PRICE / READ_PRICE / CHECK_PRICE / NEWS_PRICE / TOKEN_PRICE | $0.01 / $0.005 / $0.005 / $0.005 / $0.002 | Per-call prices |
SOL_PRICE / BALANCE_PRICE / TX_PRICE / GAS_PRICE | $0.002 / $0.003 / $0.003 / $0.002 | Per-call prices for /solana-price, /balance, /tx, /gas |
NEWS_GKG_HOURS | 24 | Hours of the GDELT GKG 15-minute news index kept in memory (0 = off). ~2.5 MB download per 15 min, ~50k headlines/day, ~60 MB RAM |
NEWS_GDELT_API | off | 1 = also query the GDELT DOC API (rate-limited; adds latency) |
TRAFFIC_FILE | ./data/traffic.json | Where /stats counts are saved (every 10 min + on shutdown). off = memory only. Render free has no persistent disk, so counts reset on each deploy unless you mount a disk here |
SOLANA_RPC_URLS | Solana Foundation + PublicNode | Comma-separated Solana RPC URLs (first healthy one wins) |
PUBLIC_URL | Render URL | Used in discovery docs |
DAILY_SPEND_CAP_USD | 50 | Runaway guard on confirmed settlements per UTC day |
GROK_API_KEY or OPENAI_API_KEY | — | Optional: LLM synthesis over the cited sources; without it /report is extractive |
SERPER_API_KEY | — | Optional: Serper (Google results API) as the first /search source (5 s timeout); on error/quota or if unset, falls back to Brave → DuckDuckGo → Bing → Bing RSS → Wikipedia, topping up short result lists |
Free routes: /health, /stats, /examples, /llms.txt, /openapi.json, /.well-known/x402, /robots.txt, /icon.png (/icon.svg).
Answer permalinks (/a/<id>)
Every paid /report answer gets a free shareable page at /a/<id> (clean HTML; ?format=json for the stored JSON) with a footer link back to the service. Stored in memory only (max 500, 30 days), so links reset on each Render deploy/restart. Only the answer is stored (question, answer, sources), never IP, user agent or payer. /a/example-mcp is a pinned demo. The paid response leads with bot-friendly fields: answer, answer_citations, key_points[{text,citations}], sources with publisher, published, quote, confidence + confidence_why, checked_at, permalink; the original fields (summary, bullets, ...) are unchanged.
Interest tracker (/stats)
Open /stats in a browser (or /stats?view=simple) for a plain-English page: one headline sentence, a per-tool table (looked at price / paid / bots-crawlers), Pacific times. Programs get JSON (default, or ?format=json). Payments signed by our own test wallet (SELF_PAYERS, default 0x4862…4940) and the unpaid probe just before them from the same visitor are tagged self and excluded from buyer counts (selfPaid shows them).
Per paid route and per hour / UTC day: unpaid 402s, paid 200s, settle failures, rejected payments, uncharged
errors and unique visitors, split by visitor class: client (anyone who sends a payment, or a non-bot user agent such
as node, python, curl, a browser), crawler (CDP Bazaar, x402scan, 402index, other x402 directories), pinger
(cron-job.org, UptimeRobot, ...), bot (search/AI crawlers, scanners, empty UA), head (HEAD/OPTIONS) and self
(scripts/rank-check.mjs). Visitors are sha256(random daily salt + IP + UA); raw IPs are never stored and the salt
never leaves memory. /health carries a compact traffic block; /stats has today, yesterday, last 7 days, 48 hourly
and 35 daily buckets, top user agents and definitions. Memory use is a few hundred KB.
Discovery and ranking
- Every paid route declares
extensions.bazaar (input schema + example, typed output schema + example) and
resource.serviceName / tags / iconUrl / mimeType, per the x402 Bazaar spec.
- CDP Bazaar indexes a route after its first CDP-settled payment and refreshes ranking every ~6 h
(30-day calls, unique payers, metadata quality, availability). Routes with no settlement for 30 days drop out.
node scripts/rank-check.mjs prints the recurring checklist (live status, Bazaar listing + rank per query with and
without the Base filter, CDP validate, on-chain sales, /stats interest tracker, x402scan presence).- What moves Bazaar search order (CDP docs + observed rankings): relevance of
serviceName, tags and description to
the query (hybrid text + semantic search), blended with 30-day unique buyers, settled calls, recency and metadata
completeness; recomputed about every 6 h; results are capped per domain; indexed metadata only refreshes after a new
CDP-settled payment.
Guard rails
- Settlements are logged to
payments.jsonl (gitignored) only after the facilitator confirms, with payer + tx hash.
- Circuit breaker: 3 failed settlements (verified payment, settle failed) in 10 minutes -> 503 (uncharged) for paid calls.
/news sources: the GDELT GKG 15-minute files (open data, cite gdeltproject.org; indexed in memory so no API rate
limits), Hacker News (Algolia API) and ~26 publisher RSS/Atom feeds (cached 10 min). Only headlines, links, outlet and
time are returned, never article text./price reads Uniswap v3 pool state (slot0, reserves) straight from public RPC nodes via Multicall: no third-party
price API, so every number is verifiable onchain at the returned block. Pools under $25k quote-side depth are ignored;
no qualifying pool -> 422 (uncharged). 24h change comes from the deepest pool's own TWAP oracle (observe) or an
archive slot0 read ~24 h of blocks back. Cached 30 s./solana-price (and /price for Solana) derives Orca Whirlpool, Raydium CLMM, PumpSwap and pump.fun bonding-curve
accounts by PDA and reads them from public Solana RPC (no indexer, no API key). Not covered: Raydium AMM v4, Meteora.
No 24h change on Solana (public RPC keeps no price history). Under $5k depth -> 422; under $25k -> thinLiquidity./balance, /tx, /gas read public RPC nodes only (Multicall3 on EVM). Balances cover native + a curated list of
major tokens per chain plus any tokens= you pass (public RPC does not index every token a wallet holds)./read and /check only fetch public https hosts (private/loopback/link-local IPs blocked, redirects re-checked, 3 MB / 15 s caps).
MIT-style: use freely. No secrets in this repo; never commit .env.