Live on Base mainnet

Know who you're
transacting with - before you send.

Basecheck turns any Base wallet or contract address into a plain-English activity and risk summary, backed by live onchain data. Priced per call in USDC via x402 - no subscriptions, no checkout page, no API keys to issue.

⬢ Base mainnet (eip155:8453) ⟡ Coinbase CDP facilitator ◈ Bazaar-discoverable ✓ No signup required
Try it right now

Pay $0.03, get a real answer

This calls the live Basecheck API with your own wallet, right in this page - no backend of ours in between. You'll sign one payment authorization for $0.03 USDC on Base mainnet; nothing is charged until you approve it in your wallet.

Prefilled with Base's USDC contract address - swap in any Base address you want checked.
How it works

One request. One inline payment. One clear answer.

No API keys, no dashboard, no monthly plan. A caller - human, script, or another AI agent - just sends the address and pays for that single call, right inside the HTTP request.

1

Send an address

POST the Base wallet or contract address you want checked to /wallet-summary. No account, no key.

2

Pay $0.03 in USDC, inline

The server replies 402 with a price quote. The caller signs a payment authorization and retries - settled on Base by Coinbase's facilitator.

3

Get a plain-English read

Real Blockscout data - balance, activity, failures, counterparties - reduced to deterministic flags and a short LLM summary.

Example

What you get back

A real request/response shape - the flags are computed straight from onchain data, not left for the model to invent.

request
# pay-per-call - no API key needed
curl -X POST https://basecheck.up.railway.app/wallet-summary \
  -H "Content-Type: application/json" \
  -d '{"address":"0x8335...a02913"}'
response · 200 OK
{
  "address": "0x8335...a02913",
  "summary": "This address shows steady,
    diverse activity with no failed
    transactions and a wide set of
    counterparties - consistent with
    an active, established contract.",
  "flags": [],
  "facts": {
    "ethBalance": "0.009801",
    "recentTransactionCount": 50,
    "failedTransactionCount": 0,
    "uniqueCounterparties": 42
  }
}
Balance
ETH balance, live
Activity
Up to 50 recent transactions
Reliability
Failed-tx count
Diversity
Unique counterparty count
Timeline
Oldest → newest activity
Behavior
Up to 8 decoded function calls
Deterministic flags, not vibes. Things like "no transaction history," "recent failed transactions," or "all activity with a single counterparty" are computed directly from the data before the LLM ever sees it - auditable, not hallucinated.
Pricing

Pay per call. Nothing else.

No subscriptions, no minimums, no rate-limited free tier to fight over. Every price is quoted upfront in the 402 response before you commit.

Building block
POST /summarize
$0.01 / call
Summarize any block of text with AI.
Building block
POST /generate
$0.05 / call
Generic AI text generation from a prompt.
Built for agents

Made to be called by machines, not just people

Basecheck is designed for the world where wallets, dApps, and autonomous agents check each other out before transacting - not just for humans reading docs.

✓ No API keys, ever

Nothing to sign up for and nothing to leak. Payment itself is the auth - pay per request, inline with the HTTP call.

◈ Bazaar discoverable

Basecheck declares itself to x402's Bazaar discovery layer, so agents can find it, read its price and shape, and call it automatically - no docs required.

⬢ Settled on Base

Payments settle in USDC on Base mainnet via Coinbase's CDP facilitator - production-grade, not a testnet demo.

⚑ Trust, before you transact

Ask "should I trust this counterparty?" or "sanity-check this wallet" before letting a transaction go through - in one call.

Under the hood

Technical specs

Network
Base mainnet · eip155:8453
Payment protocol
x402 (exact / EIP-3009)
Facilitator
Coinbase CDP
Onchain data
Blockscout (base.blockscout.com)