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

Read-only probes

MCP server · Code & DevOps

402xAgent

Check an x402 endpoint before your agent pays: pay, skip or recheck, with Ed25519-signed receipts.

Checks passed
13 / 22

1 failed · 8 not measured

Median response
89 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
12

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Outdated check

Last connection measurement is over 24 hours old. Current availability is unknown.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
310
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 89 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name 402xagent.

  • Pass
    Lists tools

    tools/list returned 12 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 89 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 89 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

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

    37 of 41 parameters have a description (90%). The bar is 80%.

  • Fail
    Safety hints

    4 tools set neither readOnlyHint nor 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 2026-11-03T16:36:13.9109Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using 402xAgent

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 402xagent https://api.402xagent.com/mcp

Capabilities

Tools 12

discover

Free discovery of x402 pay-per-call endpoints from 402xAgent's weekly crawl. Returns up to 20 endpoints matching the words in q (URL or source list), each with the verified (quoted) price, network, last_checked, stale flag, verdict pay|skip|recheck with its reason, and a receipt. Skips are included by default; pass verdict to filter. A result older than 36 h is stale; a pay whose terms are older than 7 days (TERMS_MAX_AGE_HOURS) is returned as recheck (reason_code terms_stale). Run endpoint_spot_check right before paying (pass quote=<result receipt_id> to be told if the live terms moved). Read-only, no auth, 60 calls per minute.

Discovered
endpoint_report

Paid ($0.05 USDC on Base via x402, no free tier): the exact committed snapshots behind endpoint_spot_check's locked teasers: which payment terms changed in the last 30 days, when, from what to what, and the full hygiene checks. Pass the url and the commitment_ref from the free answer's locked_commitments; verify each revealed {snapshot, nonce} against its sha256 digest (docs: https://402xagent.com/docs#endpoint-report).

Discovered
endpoint_spot_check

Decision-shaped 402xAgent check of a public URL (private, loopback and link-local addresses blocked on every redirect hop) for an x402 PAYMENT-REQUIRED / 402 challenge. Every answer has reason_code (stable code) and confidence (high|medium|low); rules: https://402xagent.com/rules.json. History: stable_for_days, last_changed, drift, days_observed, first_seen, last_checked. Free: verdict (pay|skip|recheck), a plain-words reason, payment_terms_sha256 (hash of the approved payment), and access. Paid: verdict, reason code, quoted/claimed price, pay_to, network, asset, and payment = the exact {network, asset, amount_atomic, amount_usd, pay_to} a router may sign (verdict pay only), plus access with the settlement tx. No 402 terms is skip/no_paywall (recheck/free_trial_active when the target sends x-free-trial headers); recheck only for timeouts, 5xx, network errors and (0.55.0) HTTP 429 (rate_limited), a 403 with a firewall/WAF challenge signature (waf_challenge) or a host that still does not resolve after one retry (dns_error); after 24 h (TRANSIENT_SKIP_AFTER_HOURS) of only those rechecks the endpoint falls back to skip (*_persistent); (0.56.0) recheck/timeout when the whole probe (redirects + body) exceeds PROBE_TIMEOUT_MS (default 8000 ms), and recheck/host_unstable while the per-host circuit breaker is open (3 failed probes of the host in 10 min -> 15 min pause; target not fetched, no free check used, never charged); (0.57.0) before a live pay (after the free check or payment is accepted) a second quick probe of the same target must read the same 402 terms (scheme, network, asset, payTo; amount within 1%): different terms are recheck/terms_unstable, a failed confirm probe is its own recheck (server_error, timeout, unreachable); same price and free check; a plain 403 stays skip/no_paywall; wrong or unsupported network, non-canonical USDC or a pay_to that differs from the listing is skip. The same normalized URL + method reuses one probe for 5 min, so consecutive calls agree. mode=dry-run: free dry run (nothing signed or paid, stored as a public receipt, no approval hash, 50/caller/day). Never pays the target (probe GET only). 5 free checks per client per UTC day (at most 25 per network) (client=vc-mcp), then $0.02 USDC a check on Base via x402. Unpaid after free quota: payment instructions. Forward PAYMENT-SIGNATURE for a paid check.

Discovered
get_overnight_cos_pack

Buy and download the Overnight Chief of Staff Setup Pack ($9 USDC on Base via x402): 5 ready-to-paste bot prompts, an HTML morning-briefing template, and a PDF setup guide. Always paid — no free quota. Call without PAYMENT-SIGNATURE to receive payment requirements and the HTTP endpoint URL. Agents pay by retrying the HTTP endpoint (or this MCP call) with a PAYMENT-SIGNATURE header holding a signed USDC EIP-3009 authorization.

Discovered
get_receipt

Free: read a public 402xAgent receipt. Give id (sc-... from endpoint_spot_check's receipt_id, or a 10-hex crawl id) or url (latest live + crawl receipt for that URL). Receipts hold the listing URL, the live 402 terms, verdict, reason, reason_code, confidence, history summary, timestamp, and a status-badge embed snippet (badge.markdown / badge.html). Does not run a fresh check (use endpoint_spot_check for that).

Discovered
get_service

Fetch the complete catalog record for one known service id (e.g. from search_catalog or lookup results). Use search_catalog to find ids and lookup to rank services for a task; get_service has no per-call receipts, so for receipts with tx and Basescan links call lookup with endpoint=<id>. Read-only. No auth or API key; free, no quota (reads the same catalog snapshot as search_catalog). Returns the record as published: id, name, provider, category, description, endpoint, advertised_price (USD, atomic, asset, network), sample_request, tasks, quality_test (known-answer test, facts_only flag and reason), paid_receipts (count), latest (full last check incl. x402_challenge, error, raw_log_url), history_summary and page_url. Unknown or missing id: error "no service with id ...".

Discovered
lookup

Rank x402 endpoints for a known task at or under a price: "which endpoint should I pay for task X at <= $Y?". Prefer it over search_catalog (keyword browsing, unranked) and get_service (one id's raw record). No auth or API key. Calls the hosted lookup service as client=vc-mcp; all MCP users share that client's 5 free lookups per UTC day (reset 00:00 UTC), after which the tool returns an error reporting the HTTP 402 ($0.02 USDC on Base via x402) and never pays. Returns results sorted by known-answer pass_rate over the last n paid calls, then price, each with price_usd, pass_rate, last_check_at, last_check, stale and receipts (time, tx, basescan_url, charged_usd, delivered, quality); seller-broken services come unsorted under facts_only. No match: empty results, matched 0. Needs task or endpoint; invalid params return an error. Payment never changes results.

Discovered
page_to_markdown

Fetch one public web page and return clean, LLM-ready Markdown of its main content (no nav, footers, ads or cookie banners; absolute links; tables kept) plus title, description, links, word_count and token_estimate. Respects robots.txt; skips login walls, paywalls and 401/403 pages (never charged). 3 free pages per day, then $0.002 USDC on Base via x402: retry with the PAYMENT-SIGNATURE header.

Discovered
payment_status

After you pay an x402 endpoint (Base USDC, EIP-3009 exact): did the payment land, and is it safe to sign a new one? Give payment_payload (the base64 PAYMENT-SIGNATURE you sent), or tx_hash, or from + nonce (+ valid_before). Returns status landed|not_landed|pending|canceled|unknown, safe_to_retry_same_payload (always true: a nonce is single-use), safe_to_resign (true only when two independent RPC sources agree the nonce is unused AND validBefore has passed), tx details, terms match, a claim pointer and a signed receipt. Same 5 free per UTC day as endpoint_spot_check (client=vc-mcp), then $0.02 USDC on Base via x402 (forward PAYMENT-SIGNATURE).

Discovered
pdf_tables

Extract the tables (CSV, JSON, Markdown) and per-page text from one PDF at a public URL. Digital PDFs ~97% cell accuracy; scanned pages (OCR) ~80%. Priced per page via x402 USDC on Base: $0.005/page with ocr=never, $0.015/page with ocr=auto. Charged only if every page succeeds. Max 20 pages per call. Retry with the PAYMENT-SIGNATURE header.

Discovered
search_catalog

Browse or keyword-search the verified catalog of pay-per-call (x402) agent services. Use it when you don't know the task name or want to see what exists; use lookup to rank endpoints for a known task at a max price, and get_service for one id's full record. Read-only. No auth or API key; free, no quota or per-client limit: it only reads the catalog snapshot (bundled catalog.json in the local server, the published catalog.json on remote /mcp). Returns {count, results, generated_at, note, methodology_url}; results are in catalog order, ungraded, each with id, name, category, endpoint, advertised_price_usd, page_url and latest (checked_at, reachable, http_status, latency_ms, quoted_price_usd, price_matches_listing, charged_price_usd, delivered_valid, raw_log_url). No match: count 0, empty results. A non-numeric max_price_usd or limit returns an error.

Discovered
x402_hygiene

Free x402 hygiene score for an endpoint you run: {score, grade, deductions[{code, points, fix}]} from normal unpaid requests (never pays, never sends bad params). 20 per day per network, cached 24 h. Grades are returned only to you.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected89 ms12