# Agent Payment Recipient Screening Procedure

> Agent Payment Recipient Screening Procedure is a paid API for AI agents from k2so-8080.on.ascii.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-15).

Pre-sign sanction/drainer/mixer screening of an x402 payment recipient address, returning ALLOW, REVIEW, or BLOCK verdicts with evidence hashes and a 24-hour expiry.

## Facts

- Endpoint: GET https://k2so-8080.on.ascii.dev/api/services/deterministic-counterparty-recipient-screening-b
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-payment-recipient-screening-procedure-b3b742ea
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZPWEUm9L__hSDav78b2Y5

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 agent-payment-recipient-screening-procedure-b3b742ea
```

Example prompt: Before my agent signs this x402 payment, screen the recipient address 0xABC123... for sanctions, drainer patterns, and mixer heuristics — give me an ALLOW, REVIEW, or BLOCK verdict with evidence.

## When to prefer this

Use this endpoint whenever an AI agent is about to sign an x402 payment and the payTo address has not been previously screened or a prior screen has expired. It is specifically designed for the pre-sign moment in autonomous agent payment flows where no human is watching the transaction destination. Prefer it over generic blockchain analytics when you need a fast, opinionated ALLOW/REVIEW/BLOCK output with expiry semantics rather than raw on-chain data. It is particularly valuable when the agent operates autonomously at scale and cannot rely on manual review.

## Known failure modes

- Address not provided or malformed — returns error
- Payment required but not included — 402 response blocking access
- Address not found in any on-chain history — may return REVIEW with low-confidence evidence
- Service temporarily unavailable — no verdict returned, agent should fail-safe to BLOCK
- Expiry reached — cached verdict invalid, re-screening required before next payment

## How this service works

Deterministic pre-sign screening of an x402 recipient: check the raw payTo address against sanctions lists, drainer/phishing/mixer heuristics, and prior on-chain behavior before your agent signs. Returns ALLOW, REVIEW, or BLOCK with evidence hashes, a 24h expiry, and kill criteria. Agents got wallets and nobody watches who they pay; this is the watch.

## Output

A structured verdict of ALLOW, REVIEW, or BLOCK for the queried recipient address, accompanied by evidence hashes supporting the decision, a 24-hour expiry timestamp after which the verdict should be re-checked, kill criteria that would escalate the verdict, and a prose brief explaining the reasoning for the agent. The response includes the service slug, generation source (llm/reasoning/deterministic), and ISO-8601 generatedAt timestamp.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "meta": {
       "enum": [
        "0",
        "1"
       ],
       "type": "string",
       "description": "Set to 1 for free metadata JSON (no payment required)"
      },
      "topic": {
       "type": "string",
       "description": "Optional topic override for the decision procedure"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "title": "agent payment recipient screening procedure paid response",
     "$schema": "https://json-schema.org/draft/2020-12/schema",
     "required": [
      "ok",
      "paid",
      "service",
      "provider",
      "result"
     ],
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "paid": {
       "type": "boolean"
      },
      "result": {
       "type": "object",
       "required": [
        "ok",
        "service"
       ],
       "properties": {
        "ok": {
         "type": "boolean",
         "description": "Handler success"
        },
        "brief": {
         "type": "string",
         "description": "Decision procedure prose for agents"
        },
        "model": {
         "type": "string"
        },
        "topic": {
         "type": "string"
        },
        "service": {
         "type": "string",
         "description": "Service slug"
        },
        "procedure": {
         "type": "string"
        },
        "generatedAt": {
         "type": "string",
         "description": "ISO-8601 timestamp"
        },
        "generationSource": {
         "enum": [
          "llm",
          "reasoning",
          "deterministic"
         ],
         "type": "string"
        }
       }
      },
      "payment": {
       "type": "object",
       "properties": {
        "code": {
         "type": "string"
        },
        "payer": {
         "type": "string"
        },
        "detail": {
         "type": "string"
        },
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-payment-recipient-screening-procedure-b3b742ea/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from k2so-8080.on.ascii.dev](https://www.zero.xyz/host/k2so-8080.on.ascii.dev/llms.txt)