Can I enter?

// npm i @x402/fetch @x402/evm viem   (Node 18+)
// WARNING: running this spends real USDC ($0.03/call, Base mainnet).
// Inspect the offer first, free of charge:
const probe = await fetch("https://api.canienter.com/v1/check?passport=NLD&destination=JPN");
console.log(probe.status, /* 402 */ JSON.parse(atob(probe.headers.get("PAYMENT-REQUIRED"))));

// Then pay per call — key from an env var, never hardcoded or logged:
import { wrapFetchWithPaymentFromConfig } from "@x402/fetch";
import { ExactEvmScheme } from "@x402/evm";
import { privateKeyToAccount } from "viem/accounts";

const account = privateKeyToAccount(process.env.X402_PRIVATE_KEY);
const payFetch = wrapFetchWithPaymentFromConfig(fetch, { schemes: [
  { network: "eip155:8453", client: new ExactEvmScheme(account) }]});

const res = await payFetch(
  "https://api.canienter.com/v1/check?passport=NLD&destination=JPN");
if (!res.ok) throw new Error("check failed: " + res.status);
const { requirement, allowed_stay_days } = await res.json();

# The API publishes its own agent skill (Claude Code paths shown;
# Codex/Cursor/other agents: use your agent's skills directory)
mkdir -p ~/.claude/skills/visa-check
curl -s "https://api.canienter.com/.well-known/agent-skills/visa-check/SKILL.md" \
  -o ~/.claude/skills/visa-check/SKILL.md

# Discovery index with the SKILL.md sha256 digest (verify, updates, extras):
curl -s "https://api.canienter.com/.well-known/agent-skills/index.json"

# Remove: delete ~/.claude/skills/visa-check

有了这个技能，智能体就能查询入境要求，并通过 x402 按次付费。全程不涉及 API 密钥，也就没有泄露风险。