x402 Checker (AI Nock) is an MCP server with 43 tools an agent can call, among them arxiv, bid, bizdays. It answers at https://x402-checker.nock-for-mak.workers.dev/mcp over streamable HTTP, and it listed its tools to an anonymous client, so no sign-in was needed for that. Our probes reached it 6 of 6 times since 11 September 2026; the last check, on 22 October 2026, succeeded.
Free check/board/name; paid bid/report 0.05, 1c fx/wx/lookups, news 0.001.
Description as the publisher wrote it.
| Tool | What it does |
|---|---|
arxiv | Paid $0.01 USDC exact on Base: academic paper search via public arXiv Atom API. q= required (or id=2605.11781). Optional cat=cs.CR, sort=relevance|date|updated, hits=1..8. Metadata only; no PDF fetch. Complements /hn. payTo 0x3903F05a176765 Inputs: q, id, cat, sort, hits |
bid | Paid $0.05 USDC exact on Base: bid on the pay-to-rank board. Each verified bid ADDS to that origin's 24h total. Listing URL must return HTTP 402 (or be this origin). http(s) only. No telegram/discord/whatsapp. payTo 0x3903F05a17676566958B0a Inputs: url, name, description, topic, slot |
bizdays | Paid $0.01 USDC exact on Base: US federal business-day calendar. date=YYYY-MM-DD (default today UTC) or start=&end= range (cap 366). Holidays 2025-2027 baked in, observed weekday rules. No API keys. payTo 0x3903F05a17676566958B0a3E0c21E0bd4 Inputs: date, start, end, tz |
block | Paid $0.01 USDC exact on Base: block header via public RPC. Default n=latest. Accepts latest|earliest|safe|finalized, a decimal, 0x number, or hash=. Rejects pending. Returns number, hash, timestamp, miner, txCount, gasUsed, gasLimit, baseF Inputs: n, hash |
board | FREE pay-to-rank board by AI Nock. Rank listings by USDC bid total in the last 24 hours. Empty JSON still sells: how/next point at unpaid POST /bid $0.05, POST /name $0.05, free GET /check (listing gate), GET /find $0.01. payTo on the JSON. |
check | FREE x402 wash/honesty probe by AI Nock. Fetches an http(s) 402 URL with no payment headers. Returns payTo, amount, network, asset, facilitator if present, payToKind, a short risk note, and JSON next always: report $0.05, bid $0.05, name $0 Inputs: url |
check_batch | Paid $0.01 USDC exact on Base: batch x402 honesty probes (max 10 URLs). Each result is the same shape as free check (next.report $0.05, next.bid $0.05, next.name $0.05, next.board free, next.check_batch $0.01; when has402 also next.sanction Inputs: urls |
cron | Paid $0.01 USDC exact on Base: unix cron parser. expr required. Optional tz (default UTC) and n (1-20, default 5). Returns next fire times in UTC and America/Denver. No API keys. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: expr, tz, n |
crypto_news | Paid $0.001 USDC exact on Base: public crypto RSS recap (CoinDesk, The Block, Decrypt, Base blog). Optional topic filter. Cache ~15 minutes. No API keys. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: topic |
cve | Paid $0.01 USDC exact on Base: CVE / NVD vulnerability lookup via public NIST NVD 2.0. id=CVE-2021-44228 or q=log4j. Optional severity=low|medium|high|critical, hits=1..8. NVD-only metadata; no exploit/PoC. Complements /sanctions /tsec. pay Inputs: id, q, severity, hits |
dex | Paid $0.01 USDC exact on Base: DexScreener pairs by token address=0x or search q=. Optional chain= filter. Ranked by liquidityUsd (max 5). Not investment advice. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: address, q, chain |
domain | Paid $0.01 USDC exact on Base: DNS/RDAP/TLS/SPF/DMARC dossier for a public hostname. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: host |
email | Paid $0.01 USDC exact on Base: email syntax + MX via DoH (no SMTP). Disposable domains and MX-absent = invalid. Fail closed on lookup errors. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: addr |
ens | Paid $0.01 USDC exact on Base: resolve an ENS or Basename (must end in .eth, including foo.base.eth). Public HTTP resolvers. Unresolved names return resolved:false after payment. Not POST /name (that is this origin's 30-day agent registrar) Inputs: name |
find | Paid $0.01 USDC exact on Base: search this origin's free + paid catalog by keyword q=. Optional limit=1..20. House discovery (board/bid/name + SKUs). Not a global index. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: q, limit |
fng | Paid $0.01 USDC exact on Base: Crypto Fear & Greed Index via public alternative.me. Optional limit=1..30 (default 1). Not investment advice. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: limit |
fx | Paid $0.01 USDC exact on Base: fiat FX via Frankfurter/ECB. from= (default USD), to= comma list (default EUR), amount= (default 1). Fiat only — use /price for crypto. Not investment advice. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: from, to, amount |
gas | Paid $0.01 USDC exact on Base: live Base gas oracle via public RPC (gasPrice, maxPriorityFee, feeHistory). Optional chain=base. Returns gwei fields + suggestedMaxFee. Read-only. No API keys. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: chain |
geo | Paid $0.01 USDC exact on Base: forward geocode with q= or reverse with lat=&lon= via public Nominatim (OpenStreetMap). Attribution required. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: q, lat, lon |
gh | Paid $0.01 USDC exact on Base: GitHub public REST lookup via api.github.com (keyless). mode=search|repo|user (default search). search: q=. repo: owner=&repo= or full=owner/repo. user: user= or login=. Public metadata only; no token, no priv Inputs: mode, q, owner, repo, full, user |
headers | Paid $0.01 USDC exact on Base: raw HTTP header dump of a public URL (not an honesty probe, not markdown). payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: url |
hn | Paid $0.01 USDC exact on Base: Hacker News search via public Algolia HN API. q= required. Optional tags=story|comment|ask_hn|show_hn|poll|job|front_page|all, sort=relevance|date, hits=1..8. Complements /crypto-news. payTo 0x3903F05a17676566 Inputs: q, tags, sort, hits |
json | Paid $0.01 USDC exact on Base: validate JSON data against a JSON Schema (tiny built-in subset, no $ref). payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: schema, data |
md | Paid $0.01 USDC exact on Base: fetch a public http(s) URL and return simple HTML-to-text markdown. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: url |
name_lookup | FREE ENS-style agent name lookup by AI Nock. n= lowercase [a-z0-9-] 3-32. If unset/unclaimed: taken false plus how/next pointing at unpaid POST /name $0.05 (HTTP 402), free GET /board, free GET /check (origin gate), GET /find $0.01. payTo + Inputs: n, name |
name_register | Paid $0.05 USDC exact on Base: register or extend an ENS-style agent name for 30 days. origin must be https and return HTTP 402 (or be this origin). Re-register from anyone after payment overwrites/extends. payTo 0x3903F05a17676566958B0a3E0 Inputs: name, origin, ownerHint |
now | Paid $0.01 USDC exact on Base: UTC clock (unix, ms, iso). No params. Alias of REST GET /now and /time. For IANA zones use tool tz. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. |
pm | Paid $0.01 USDC exact on Base: Polymarket market odds via public gamma-api. q= search or slug= event/market slug (not both). Optional limit=1..5. Unknown is paid 200 with found:false. Read-only. No trading. Not investment advice. payTo 0x39 Inputs: q, slug, limit |
price | Paid $0.01 USDC exact on Base: spot USD quotes via public DeFiLlama. Default ids=ETH,USDC,BTC. Optional ids= aliases (ETH,USDC,BTC,SOL,WETH,LINK,AAVE,UNI,DAI) and/or token= Base 0x (max 8). Cache ~45s. Not investment advice. payTo 0x3903F05 Inputs: ids, token |
quote | Paid $0.01 USDC exact on Base: equity/index/FX/crypto quote via public Yahoo Finance chart. symbol= (AAPL, ^GSPC, EURUSD=X, BTC-USD). Complements /price /fx. Not investment advice. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: symbol |
redirect | Paid $0.01 USDC exact on Base: follow Location redirects for a public http(s) URL (manual, max 8 hops, SSRF-safe). Returns chain, finalUrl, hopCount. No meta-refresh. No payment headers. Not /headers. payTo 0x3903F05a17676566958B0a3E0c21E0b Inputs: url |
report | Paid $0.05 USDC exact on Base: structured honesty report for this 402 (well-known payTo match, header vs body 402, bytecode snippet hash, accepts[] list). payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. REST GET /report is the same SKU. Inputs: url |
sanctions | Paid $0.01 USDC exact on Base: OFAC SDN digital-currency screen for an EVM 0x or Solana/base58 address. Fail closed. Not legal advice. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: address |
sig | Paid $0.01 USDC exact on Base: 4-byte function selector lookup via public openchain.xyz (4byte.directory fallback). hex= / selector= / data= (first 4 bytes). Unknown selector is paid 200 with found:false. Complements /tx (inputLen only). No Inputs: hex |
so | Paid $0.01 USDC exact on Base: Stack Overflow Q&A search via public Stack Exchange API. q= required (or id= question id). Optional tagged=javascript, sort=relevance|votes|activity|creation, hits=1..8. Stack Overflow only. Complements /hn an Inputs: q, id, tagged, sort, hits |
ssl | Paid $0.01 USDC exact on Base: TLS cert facts (public CT + live HTTPS HEAD) for a public hostname. Returns issuer, dates, SANs, daysRemaining, currentlyValid, liveHttps. Not the full /domain dossier. payTo 0x3903F05a17676566958B0a3E0c21E0bd Inputs: host |
token | Paid $0.01 USDC exact on Base: ERC-20 metadata via public RPC (name, symbol, decimals, totalSupply). address= required. EOA/empty code is paid 200 with found:false. Not a spot price (use /price). Not a wallet balance (use /who). payTo 0x390 Inputs: address |
tsec | Paid $0.01 USDC exact on Base: token security snapshot via public honeypot.is + DexScreener. address=0x required. Optional chain=base|eth|bsc (default base). Not a full audit. Not investment advice. payTo 0x3903F05a17676566958B0a3E0c21E0bd4 Inputs: address, chain |
tx | Paid $0.01 USDC exact on Base: transaction + receipt for a 0x hash via public RPC. Returns found, from, to, valueEth, status, gasUsed, logsCount, pending. Unknown hash is paid 200 with found:false. inputLen only. Not a mempool tip. payTo 0x Inputs: hash |
tz | Paid $0.01 USDC exact on Base: IANA timezone clock. name=America/Denver (default). Returns now, UTC offset, DST. No API keys. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. Inputs: name |
who, wiki, wx
Every block below points at https://x402-checker.nock-for-mak.workers.dev/mcp. Pick your client and copy.
claude mcp add --transport http x402-checker-ai-nock https://x402-checker.nock-for-mak.workers.dev/mcp
{
"mcpServers": {
"x402-checker-ai-nock": {
"command": "npx",
"args": ["-y", "mcp-remote", "https://x402-checker.nock-for-mak.workers.dev/mcp"]
}
}
}{
"mcpServers": {
"x402-checker-ai-nock": {
"url": "https://x402-checker.nock-for-mak.workers.dev/mcp"
}
}
}{
"servers": {
"x402-checker-ai-nock": {
"type": "http",
"url": "https://x402-checker.nock-for-mak.workers.dev/mcp"
}
}
}{
"context_servers": {
"x402-checker-ai-nock": {
"url": "https://x402-checker.nock-for-mak.workers.dev/mcp"
}
}
}{
"mcpServers": {
"x402-checker-ai-nock": {
"serverUrl": "https://x402-checker.nock-for-mak.workers.dev/mcp"
}
}
}{
"mcpServers": {
"x402-checker-ai-nock": {
"url": "https://x402-checker.nock-for-mak.workers.dev/mcp"
}
}
}name: x402 Checker (AI Nock)
version: 0.0.1
schema: v1
mcpServers:
- name: x402 Checker (AI Nock)
type: streamable-http
url: https://x402-checker.nock-for-mak.workers.dev/mcp{
"mcpServers": {
"x402-checker-ai-nock": {
"httpUrl": "https://x402-checker.nock-for-mak.workers.dev/mcp"
}
}
}{
"mcpServers": {
"x402-checker-ai-nock": {
"type": "http",
"url": "https://x402-checker.nock-for-mak.workers.dev/mcp"
}
}
}{
"mcpServers": {
"x402-checker-ai-nock": {
"url": "https://x402-checker.nock-for-mak.workers.dev/mcp"
}
}
}goose://extension?url=https%3A%2F%2Fx402-checker.nock-for-mak.workers.dev%2Fmcp&type=streamable_http&id=x402-checker-ai-nock&name=x402%20Checker%20%28AI%20Nock%29
It answered our last check on 22 October 2026 in 139 ms. Over 6 checks since 11 September 2026 it answered 6. Status here comes from Neuronto's own probes, not from the publisher.
43, as returned by the server's own tools/list on 17 September 2026: arxiv, bid, bizdays, block, board, check, check_batch, cron, and 35 more.
It answered our last check on 22 October 2026 in 139 ms. Over 6 checks since 11 September 2026 it answered 6.
Put the server under mcpServers in ~/.cursor/mcp.json with the URL https://x402-checker.nock-for-mak.workers.dev/mcp. The exact JSON is above, with the same setup for Claude Code, Claude Desktop, VS Code, Windsurf, Zed, Gemini CLI and the rest.
It listed its tools to an anonymous client, so reading the tool list needs no key. Individual tools can still ask for credentials in their own inputs.
Publisher: io.github.nock-for-mak. Endpoint host: x402-checker.nock-for-mak.workers.dev. ARD identifier: urn:air:io.github.nock-for-mak:mcp:x402-checker.
First indexed 10 September 2026. The tools are exactly what the server returned; nothing on this page
is inferred from its name. Ranking in Neuronto search is never for sale.