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Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Code & DevOps

x402 Checker (AI Nock)

By nock-for-mak Verified namespace

Free check/board/name; paid bid/report 0.05, 1c fx/wx/lookups, news 0.001.

WebsiteSource codeFinance & payments
Connect to x402 Checker (AI Nock)
Checks passed
15 / 22

0 failed · 7 not measured

Median response
66 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
43

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
103
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 58 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name x402-checker.

  • Pass
    Lists tools

    tools/list returned 43 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 66 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 73 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    92 of 92 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Not measured
    Website matches publisher

    This namespace is not a reverse domain, so the website comparison does not apply.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Pass
    Repo owner matches

    The GitHub repository owner matches the namespace login.

  • Pass
    Recently updated

    Updated 2026-08-28T16:15:31.577319Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using x402 Checker (AI Nock)

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http x402-checker-ai-nock https://x402-checker.nock-for-mak.workers.dev/mcp

Capabilities

Tools 43

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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. REST POST /bid is the same SKU.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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, baseFee. Unknown id is paid 200 with found:false. No full txs. Not a mempool tip. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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. No self-pay. Does not spend money. REST GET /board is the same SKU.

Discovered
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 $0.05, board free, check_batch $0.01, quote $0.01; when has402, report/bid URLs are prefilled and next.sanctions $0.01. Use before paying any x402 resource. Does not spend money.

Discovered
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.sanctions $0.01). GET /check stays free for one URL. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. REST POST /check/batch is the same SKU.

Discovered
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.

Discovered
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.

Discovered
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. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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.

Discovered
domain

Paid $0.01 USDC exact on Base: DNS/RDAP/TLS/SPF/DMARC dossier for a public hostname. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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.

Discovered
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). payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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 private repos. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
headers

Paid $0.01 USDC exact on Base: raw HTTP header dump of a public URL (not an honesty probe, not markdown). payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
json

Paid $0.01 USDC exact on Base: validate JSON data against a JSON Schema (tiny built-in subset, no $ref). payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
md

Paid $0.01 USDC exact on Base: fetch a public http(s) URL and return simple HTML-to-text markdown. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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 + noSelfPay + TTL 30d. If set: origin, ownerHint?, expiresAt. Does not spend money. REST GET /name is the same SKU.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0. REST POST /name is the same SKU.

Discovered
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.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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.

Discovered
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.

Discovered
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). Not a full ABI decoder. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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 and /arxiv. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
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.

Discovered
who

Paid $0.01 USDC exact on Base: isContract, ETH balance, USDC balance, tx count for an address. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
wiki

Paid $0.01 USDC exact on Base: Wikipedia lead summary via public Wikimedia REST + MediaWiki search. q= search or title= page title (wikipedia.org URLs ok). Optional lang=en|simple, hits=1..8. Lead extract only, CC BY-SA. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered
wx

Paid $0.01 USDC exact on Base: current weather via public Open-Meteo. q= place and/or lat=&lon=. Optional units=metric|us. Attribution required. Complements /geo /tz. payTo 0x3903F05a17676566958B0a3E0c21E0bd49B66ea0.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected58 ms43
Connected74 ms43

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