# LION OFAC Sanctions Screen (x402, keyless)

> LION OFAC Sanctions Screen (x402, keyless) is a paid API for AI agents from lion-x402.lionmaster-operations.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Screens a blockchain address against the US Treasury OFAC SDN sanctions list and returns a sanctioned/not-sanctioned verdict with confidence score, no API key required.

## Facts

- Endpoint: GET https://lion-x402.lionmaster-operations.workers.dev/api/x402/sanctions-screen-json
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/lion-ofac-sanctions-screen-x402-keyless-b1b622a4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1mTzTY73eRbf7QWcGxBRp

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability lion-ofac-sanctions-screen-x402-keyless-b1b622a4
```

Example prompt: Can you check if the wallet address 0x8589427373D6D84E98730D7795D8f6f8731FDA16 is on the OFAC SDN sanctions list? I need to know if it's sanctioned before I proceed with this transaction.

## When to prefer this

Use this endpoint when you need a fast, keyless, pay-per-call OFAC sanctions screening for a single blockchain/Ethereum address without signing up for a compliance data provider. Ideal for AI agents in DeFi, crypto payments, or Web3 workflows that need on-demand AML compliance checks at $0.005 per call with no subscription overhead.

## Known failure modes

- Invalid or malformed Ethereum address returns an error or unresolved result
- Payment failure via x402 blocks the request with a 402 Payment Required response
- Stale snapshot if the OFAC list has not been refreshed recently (check snapshot_as_of)
- Address not found returns sanctioned: false but resolved: true, not an error
- Network or worker timeout on the Cloudflare Workers edge

## How this service works

Keyless off-chain and on-chain data for AI agents. No API key, no signup - payment is the only gate. Pay-per-call in USDC on Base via x402.

## Output

Returns a JSON object containing: the name of the sanctions list checked (US Treasury OFAC SDN), the snapshot date of the list, the queried address, whether it matched (sanctioned: true/false), a confidence score (0–1), the asset/list ID, the resolution status, and the total number of sanctioned addresses in the dataset.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "address": {
       "type": "string",
       "description": "EVM address to OFAC SDN / sanctions screen"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "list": "US Treasury OFAC SDN (Specially Designated Nationals)",
  "as_of": "2026-06-03T00:00:00.000Z",
  "match": "0x8589427373D6D84E98730D7795D8f6f8731FDA16",
  "address": "0x8589427373D6D84E98730D7795D8f6f8731FDA16",
  "asset_id": "LION_OFAC_SANCTIONS_001",
  "resolved": true,
  "confidence": 1,
  "sanctioned": true,
  "snapshot_as_of": "2026-06-03",
  "total_sanctioned_addresses": 1234
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/lion-ofac-sanctions-screen-x402-keyless-b1b622a4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from lion-x402.lionmaster-operations.workers.dev](https://www.zero.xyz/host/lion-x402.lionmaster-operations.workers.dev/llms.txt)