KYA scores map to five tiers with concrete payment limits. Unknown (0-19) is read-only API access. Basic (20-39) allows small transactions under $100. Verified (40-59) is the production default — standard transactions and EUR settlement. Trusted (60-79) gets higher limits and priority settlement. Enterprise (80-100) gets custom limits, EUR + GBP + USD and a dedicated relationship.

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What is KYA (Know Your Agent)?

Q: What is KYA?

KYA stands for Know Your Agent. It is AsterPay's open trust-scoring framework for AI agent wallets in payment flows. Every agent address gets a score from 0-100 across seven components: wallet age, wallet activity, sanctions screening, ERC-8004 identity, operator KYB, transaction history and trust bond. KYA is the agent-payments equivalent of KYC for humans.

Q: Is KYA open?

Yes. The KYA v1 schema is published openly at asterpay.io/.well-known/kya-schema-v1 and the scoring rubric is documented at asterpay.io/kya. AsterPay's intention is for KYA to be adopted by other facilitators and merchants as the default trust language for agent commerce — much like FICO became the default credit-score language without being owned by a single bank.

Q: How do I check an agent's KYA score?

Free GET request to https://x402.asterpay.io/v1/agent/trust-score/{address}. Returns the score, the tier, the seven-component breakdown, sanctions status and the recommended payment limits. No auth required, no rate limit for reasonable use. Batch checks (up to 50 addresses) are also free at /v1/agent/trust-score/batch.

By Petteri Lehtola, Co-founder of AsterPay · Last updated 23 April 2026 · 5 min read

Answer KYA stands for Know Your Agent. It is AsterPay's open trust-scoring framework for AI agent wallets in payment flows. Every agent address gets a score from 0 to 100 across seven components — wallet age, wallet activity, sanctions screening, ERC-8004 identity, operator KYB, transaction history and trust bond — mapped to five payment tiers. KYA is the agent-payments equivalent of KYC for humans.

Why do agent payments need KYA?

Because AI agents can spin up new wallets at zero cost and scale fraud horizontally faster than any human attacker. Traditional KYC assumes a human identity behind a card; that assumption breaks for autonomous software. KYA replaces "who is the person?" with "what is the operational reputation of this wallet?" — sanctions clean, age, activity, ERC-8004 attested, KYB-verified operator, transaction history, posted bond.

How is the KYA score calculated?

The seven components and their weights (full v1 schema at /.well-known/kya-schema-v1):

Component	Weight	What it measures
Wallet age	10	Time since first on-chain activity. Brand-new wallets score zero here.
Wallet activity	10	Volume and recency of legitimate-looking transactions.
Sanctions clean	20	OFAC / EU / UN / Chainalysis sanctions screening on every connected address.
ERC-8004 identity	15	On-chain agent identity registered, with metadata and operator binding.
Operator KYB	15	Human or company behind the agent has completed KYB through Sumsub or equivalent.
Transaction history	15	Settlement success rate, dispute rate, refund rate over the agent's lifetime.
Trust bond	15	Optional posted USDC bond that gets slashed on confirmed bad behavior.

What are KYA tiers?

Tier	Score	Permissions
Unknown	0-19	Read-only API access. Free endpoints only.
Basic	20-39	Small transactions (< $100 / day cap).
Verified	40-59	Standard transactions, EUR settlement enabled. The production default.
Trusted	60-79	Higher limits, priority settlement queue.
Enterprise	80-100	Custom limits, EUR + GBP + USD, dedicated support.

How do I check an agent's KYA score?

Free GET request, no auth, no rate limit for reasonable use:

curl https://x402.asterpay.io/v1/agent/trust-score/0xYourAgent

{
  "success": true,
  "data": {
    "address": "0x...",
    "score": 72,
    "tier": "trusted",
    "blocked": false,
    "components": { "walletAge": 8, "walletActivity": 7, "sanctionsClean": 20, ... },
    "sanctions": { "clean": true, "provider": "chainalysis" },
    "limits": { "maxPerTx": 5000, "maxDaily": 25000 }
  }
}

Batch checks for up to 50 addresses are also free at POST /v1/agent/trust-score/batch. The deeper paid endpoint /v1/agent/deep-analysis/{address} ($0.01) returns the full historical breakdown including sub-component evidence.

Is KYA open?

Yes. The KYA v1 schema is published openly at /.well-known/kya-schema-v1 and the scoring rubric is documented at /kya. AsterPay's intention is for KYA to be adopted by other facilitators and merchants as the default trust language for agent commerce — much like FICO became the default credit-score language without being owned by a single bank. The schema is versioned, comment-period-driven and open to community PRs.

How does KYA fit in the EU AI Act?

The EU AI Act classifies AsterPay's KYA layer as a limited-risk system under Article 50 (transparency obligations). Concretely: when KYA scoring affects a payment decision, the affected party (merchant or agent operator) is entitled to know that an AI/algorithmic system was involved and to an explanation of the factors. KYA's seven-component breakdown is the explanation — by design.