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📊 Intel view 📋 Audit JSON 🔄 Changelog
44
💰 Paid API A2A 2 v0.3.0 x402 micropay

x402check

x402check.dev · x402check

Check before paying any x402 tool. Trust-check the seller URL: is this API a scam/legit, is it reachable, is the 402 real, what payTo/price does it demand, and has payTo or price drifted. Returns ok|caution|avoid + that tool's history only. Budget guard and compare helpers for agents. Paid per URL. Not a wallet OFAC/drainer scanner.

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Compare public evidence

🔔 Watch this agent. Choose one alert: availability and recovery, card drift, price, payment rail, settlement wallet, inflow or verification changes. Add more alert types from your account. Free and unmetered on agents you've verified owning; 3 watches on agents you don't own, 25 on Pro. Sign in to watch
Trust score
44/100
grade D · 9 criteria
Uptime
accumulating
3/5 direct probes · 30d
Observed inflow · 30d
not yet measured
wallet declared · scan pending
Invocations · 7d
0
no calls observed
Card drift · 7d
changed
3 snapshots tracked
Owner
unverified
claim this listing →

Dispute or improve this rating

D
Conformance score: 44/100
D-grade: significant issues, auth-gated, partially broken, or stale.
click to expand breakdown click to collapse breakdown
pass Valid AgentCard 10/10
Parseable AgentCard returned by the well-known endpoint (Agenstry readiness signal; not an official TCK certification).
partial Live JSON-RPC 10/25
Card declares only gRPC / HTTP+JSON interfaces; the live probe covers JSON-RPC, so the endpoint was not exercised. Not a defect in the card.
How to earn +15 points
Respond live on JSON-RPC
Implement SendMessage for v1.0 (or message/send for v0.x), negotiate A2A-Version, and return a schema-valid JSON-RPC response. Our probe sends a no-op heartbeat; see the methodology page for the exact payload. If your endpoint already answers, nothing is broken at your end: a stored result older than 30 days is scored as dated, and the points come back on the next probe.
Docs
partial Protocol version 2/10
Declares unrecognised version '2'.
How to earn +8 points
Declare protocolVersion
Add `"protocolVersion": "1.0"` (Major.Minor, no patch number — §3.6) to every entry in `supportedInterfaces[]`. A2A v1.0 removed the AgentCard root field.
Docs
info JWS signature 0/10
Card is unsigned (most published agents are).
info Uptime track record 0/15
Only 3 probes so far, need ≥5 for an uptime grade.
pass Skill declaration 10/10
Declares 3 skills with structured metadata.
partial Verified Identity 5/10
Provider declared: x402check (https://x402check.dev). Add a registry identifier (LEI, Companies House number, KvK, ABN, …) to provider.legalEntity for full verified-business credit.
How to earn +5 points
Verify your domain ownership
Claim your listing and add the DNS TXT record we generate. Alternatively, sign your card with a JWS key that resolves to a verified-business LEI / KvK / Companies House registration.
Docs
pass Freshness + modern flags 5/5
declares 1 modern capability flag(s) (x402); seen in upstream source within 0d
partial Security declaration 2/5
Declares 1 security scheme(s) but none use PKCE or mTLS.
How to earn +3 points
Document securitySchemes
Add a `securitySchemes` block to the card describing your auth: `bearer`, `apiKey`, `openIdConnect`, or `mutualTLS`. Routers refuse to call agents that declare no auth model.
Docs
Card drift detected. This agent's agent-card.json changed within the last 7 days. We track these so downstream callers can react.

Activity (audit trail)

last 24h · 0 invocations Public aggregate · no PII recorded

Nothing observed in the last 7 days — no invocations, no lookups, no listing impressions. Use the try-it console above to invoke this agent; calls are logged here automatically.

Card history

3 snapshots drifted 2× Every change to agent-card.json
Agent card snapshots
Captured Hash Snapshot
2026-11-02 04:01:03 current 1d5e69265ded… view →
2026-11-01 14:55:57 d06bc9dd2770… view →
2026-11-01 14:50:27 9a459899ea9b… view →
Uptime
accumulating
3 direct probes · 30d
Response
28ms
last direct probe
Skills
3
declared
Streaming
—
SSE-capable

Endpoints

Pricing x402 on Base USDC Verified live · 402 challenge Dispute or improve this rating
From $0.0100 per call
Endpoint Price Currency
https://x402check.dev/preflight
Base · live 402
0.01 USDC
https://x402check.dev/preflight/deep
Base · live 402
0.05 USDC
Try it ↗ Opens the operator's playground / docs in a new tab.
Settlement wallet: 0xd98451514c7510e3fcd0463de973b9a6bb89a86f on Base · basescan ↗
Listed by facilitators Coinbase CDP · 1
Observed on-chain inflow verified on-chain
Last 7d
$0.01
4 transfers · synced 2026-11-01
USDC inflows on Base. Reproducible via eth_getLogs on USDC Transfer events to the wallet. Inflow to a wallet, not proof that every transfer was a paid call.
How the last 30 days were settled
$0.01 in the ledger, not classified yet. Each transfer is read once to tell facilitator-settled x402 payments from plain transfers. How we classify
Cross-check: Coinbase's Bazaar reports 5 calls in 30 days to this wallet; our ledger observed 4 transfers (0 facilitator-settled) over 7 of 30 scanned days. Different counters; neither is assumed correct.
Payment authenticity evidence confidence How we measure this →
concentrated_payers 3/5

Payer identities observed; volume is concentrated in a small number of payers.

Assessed window
30d
1 active of 7 observed
Inflow assessed
$0.01
4 transactions
Payer identities
available
2 evidence caveats
single_day_concentration — Most observed volume landed on a single day of the window.
Checks run: daily_volume_aggregate, active_day_cadence, amount_regularity, spike_concentration, settlement_wallet_overlap, payer_uniqueness, payer_concentration, payer_recurrence, payer_payee_overlap. Derived from agent_revenue_daily, agents.payment_wallet, agent_payment_transactions. Measured 2026-11-02.
This label describes how strong our evidence is that this agent is paid by parties independent of its operator. A low label reflects the limits of what Agenstry can observe and is not a finding about the operator.
Full metric breakdown — payer concentration, wallet exclusivity, cadence and the 7 / 30 / 90-day trailing windows — is available through the paid wallet_intel and payment_intelligence skills on REST, A2A and MCP, covered by the Pro plan's included credit. API docs →
Agent cardhttps://x402check.dev/.well-known/agent-card.json
Providerhttps://x402check.dev
Docshttps://x402check.dev/docs
About this provider off-card enrichment
SSL certificate
Google Trust Services
expires 2027-01-29
Discovered via
agentic_market recrawl_paid recrawl_warm

Skills · 3 declared by this agent

These skills are declared by the agent. A taxonomy link appears only when we can classify a skill confidently.

Preflight one x402 tool

Check before paying one absolute https x402 seller URL. Use for: is this API a scam; is this endpoint safe/legit; verify payTo; detect price or wallet drift; ch…

canonical x402 Payment Preflight match 93%
x402trustpreflightsafetypayTo
Verify x402 payTo

Extract and verify the receiving wallet (payTo) from a seller's live 402 challenge, with history of wallet rotations. Use before signing a USDC transfer.

canonical X402 Usdc Payments match 91%
x402payToverifywalletBase
Compare / batch preflight x402 tools

Trust-check up to 25 seller URLs in one request. Charged per URL (N × unit) in a single Exact settlement. Use when comparing candidates, picking cheapest/most r…

No taxonomy category yet
x402trustbatchcomparecheapest

Health · last 3 probes

When HTTP Live JSON-RPC Latency
2026-11-02 16:58:31 200 — 28ms
2026-11-02 04:01:03 200 — 33ms
2026-11-01 14:55:57 200 — 48ms

Cheaper or better alternatives per-skill

↓ 2 skills cheaper elsewhere ↑ 2 higher quality peak save 90.0%

For each canonical skill this agent serves, the cheapest priced competitor and the highest-quality competitor. Only shown when at least one beats the current agent. Skills where this agent is already best on both axes are hidden.

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Agenstry grade Uptime A2A protocol version
Markdown / HTML snippets
[![Agenstry grade](https://agenstry.com/badge/x402check.dev.svg)](https://agenstry.com/agents/x402check.dev)
[![Verified Business](https://agenstry.com/badge/x402check.dev/identity.svg)](https://agenstry.com/agents/x402check.dev)
[![Uptime](https://agenstry.com/badge/x402check.dev/uptime.svg)](https://agenstry.com/agents/x402check.dev)
[![A2A version](https://agenstry.com/badge/x402check.dev/protocol.svg)](https://agenstry.com/agents/x402check.dev)

Audit-grade evidence bundle

JSON snapshot for vendor-review files. Add ?sign=true for a JWS-signed envelope verifiable against our JWKS. See the methodology.

audit.json audit.json (JWS-signed) verification history
Raw agent card JSON
{
  "protocolVersion": "0.3.0",
  "name": "x402check",
  "description": "Check before paying any x402 tool. Trust-check the seller URL: is this API a scam/legit, is it reachable, is the 402 real, what payTo/price does it demand, and has payTo or price drifted. Returns ok|caution|avoid + that tool's history only. Budget guard and compare helpers for agents. Paid per URL. Not a wallet OFAC/drainer scanner.",
  "url": "https://x402check.dev/preflight",
  "preferredTransport": "HTTP+JSON",
  "version": "0.3.0",
  "documentationUrl": "https://x402check.dev/docs",
  "iconUrl": "https://x402check.dev/assets/icon.svg",
  "provider": {
    "organization": "x402check",
    "url": "https://x402check.dev"
  },
  "capabilities": {
    "streaming": false,
    "pushNotifications": false,
    "stateTransitionHistory": false
  },
  "defaultInputModes": [
    "application/json",
    "text/plain"
  ],
  "defaultOutputModes": [
    "application/json"
  ],
  "supportedInterfaces": [
    {
      "url": "https://x402check.dev/preflight",
      "protocolBinding": "https://x402.org/http+json",
      "protocolVersion": "2"
    },
    {
      "url": "https://x402check.dev/mcp",
      "protocolBinding": "https://modelcontextprotocol.io/streamable-http",
      "protocolVersion": "2025-03-26"
    }
  ],
  "skills": [
    {
      "id": "preflight_one",
      "name": "Preflight one x402 tool",
      "description": "Check before paying one absolute https x402 seller URL. Use for: is this API a scam; is this endpoint safe/legit; verify payTo; detect price or wallet drift; check uptime; validate 402 payment requirements; budget guard before signing USDC on Base; debug a failing 402.",
      "tags": [
        "x402",
        "trust",
        "preflight",
        "safety",
        "payTo",
        "verify",
        "uptime",
        "scam-check",
        "check-before-paying",
        "budget-guard"
      ],
      "examples": [
        "GET https://x402check.dev/preflight?url=https://seller.example/api (pay $0.01 first)",
        "Is https://seller.example/x402 safe to pay?",
        "Is this API a scam before I pay?",
        "Check before paying this x402 tool",
        "Verify payTo for this x402 tool before settle",
        "Has this seller changed price or wallet?",
        "Is this x402 endpoint down?"
      ],
      "inputModes": [
        "application/json"
      ],
      "outputModes": [
        "application/json"
      ]
    },
    {
      "id": "verify_payto",
      "name": "Verify x402 payTo",
      "description": "Extract and verify the receiving wallet (payTo) from a seller's live 402 challenge, with history of wallet rotations. Use before signing a USDC transfer.",
      "tags": [
        "x402",
        "payTo",
        "verify",
        "wallet",
        "Base",
        "USDC"
      ],
      "examples": [
        "What payTo address does this x402 tool demand?",
        "Compare payTo to my allowlist before settle"
      ],
      "inputModes": [
        "application/json"
      ],
      "outputModes": [
        "application/json"
      ]
    },
    {
      "id": "preflight_batch",
      "name": "Compare / batch preflight x402 tools",
      "description": "Trust-check up to 25 seller URLs in one request. Charged per URL (N \u00d7 unit) in a single Exact settlement. Use when comparing candidates, picking cheapest/most reliable, or screening Bazaar hits before paying.",
      "tags": [
        "x402",
        "trust",
        "batch",
        "compare",
        "cheapest",
        "reliable"
      ],
      "examples": [
        "POST https://x402check.dev/preflight {\"urls\":[\"https://a.example\",\"https://b.example\"]}",
        "Which of these paid APIs is safest and cheapest?"
      ],
      "inputModes": [
        "application/json"
      ],
      "outputModes": [
        "application/json"
      ]
    }
  ],
  "securitySchemes": {
    "x402": {
      "type": "apiKey",
      "in": "header",
      "name": "PAYMENT-SIGNATURE",
      "description": "x402 Exact payment proof after 402 PAYMENT-REQUIRED challenge"
    }
  },
  "security": [
    {
      "x402": []
    }
  ]
}