I Built a Free Compliance Auditor for AI Agent APIs — 32 Checks in 5 Seconds

Timo Petteri — Tue, 31 Mar 2026 19:59:40 +0000

AI agents are starting to transact with each other. They call APIs, send payments, and make decisions autonomously. But here's the problem: how does one agent know if another agent's API is trustworthy?

There's no standard way to verify if an API supports payment protocols, has proper security headers, publishes identity information, or follows regulatory requirements. Until now, the only option was manual review.

What I built

Probe runs 32 automated compliance checks on any API endpoint in under 5 seconds. No signup, no API key, no cost.

You paste a URL, hit "Run audit", and get a scored report covering:

Payment protocols — x402 discovery, payment metadata
Agent identity — agent.json (A2A), ERC-8004 on-chain identity
Security — SSL/TLS, DNSSEC, DMARC/SPF, CAA records, security headers, rate limiting
Discovery — MCP server, llms.txt, robots.txt AI crawler rules
Documentation — OpenAPI spec, API versioning, Sunset headers
Compliance — EU AI Act Article 14 human oversight, FATF Travel Rule, Terms of Service, Privacy Policy
Auth maturity — OAuth2, OIDC, API key detection
Trust signals — Wallet trust score, Content-Type validation, error handling

Every API gets a score from 0–100 and a grade (A+ to F).

The leaderboard

All audited APIs appear on a public leaderboard ranked by compliance score. Right now there are 180+ APIs ranked — from OpenAI and Stripe to smaller indie projects.

The top APIs earn the right to display a Probe trust badge on their site:


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[![Probe](https://getprobe.xyz/api/badge?domain=your-api.xyz)](https://getprobe.xyz)

How to Build an AI Agent That Settles Payments in EUR (x402 + SEPA Instant)

Timo Petteri — Sat, 14 Mar 2026 12:05:12 +0000

AI agents earn stablecoins. But businesses need euros. Here's how to bridge that gap in under 10 lines of code.

The Problem

Your AI agent completed a task and got paid 50 USDC on Base. Now what? The freelancer or service provider needs EUR in their bank account. Current off-ramps require manual KYC, multi-step flows, and aren't designed for autonomous agents.

The Solution: AsterPay API

AsterPay is an EUR settlement layer purpose-built for AI agents. It handles trust scoring, sanctions screening, and SEPA Instant settlement — all via API.

1. Check the agent's trust score (free)

‌`javascript const res = await fetch('https://x402.asterpay.io/v1/agent/trust-score/0x1234...'); const trust = await res.json(); // { score: 78, tier: "verified", sanctions: "clear", identity: true }‌`

2. Get a settlement estimate (free)

‌javascript const est = await fetch('https://x402.asterpay.io/v1/settlement/estimate?amount=50'); const quote = await est.json(); // { net_eur: 46.15, fee_eur: 0.50, rate: 0.933, settlement_time: "<5s" }‌

3. Or just use the MCP Server

`‌bash
npx @asterpay/mcp-server
‌`

16 tools available out of the box — trust scores, sanctions checks, settlement estimates, market data, and more.

What is x402?

x402 is a payment protocol built on HTTP 402 (Payment Required). When an AI agent hits a paid endpoint, the server returns a 402 with payment instructions. The agent pays with USDC on Base, and the response is unlocked. No API keys, no subscriptions — just pay-per-call.

KYA: Know Your Agent

AsterPay's KYA framework evaluates AI agents across 5 layers:

VERIFY — ERC-8004 on-chain identity
SCREEN — Sanctions and AML checks (Chainalysis)
SCORE — Behavioral analysis from on-chain activity
SETTLE — SEPA Instant EUR delivery
COMPLY — MiCA regulatory framework

The result is a trust score from 0-100 that any counterparty can query before transacting with an agent.

Why This Matters

The agent economy is growing fast. Agents need to:

Pay other agents and APIs (x402)
Get paid and convert to fiat (AsterPay settlement)
Prove trustworthiness (KYA scoring)

AsterPay handles all three.

DEV Community: Timo Petteri