# SYS84 Ink Agent Checkout — x402 Payment Session Initiator

> SYS84 Ink Agent Checkout — x402 Payment Session Initiator is a paid API for AI agents from api.sys84.org, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-11).

Creates an x402-compliant payment checkout session for pay-per-call API access, returning settlement and verification URLs along with encoded payment requirements.

## Facts

- Endpoint: POST https://api.sys84.org/v1/services/ink_agent_checkout?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sys84-ink-agent-checkout-x402-payment-session-initiator-4af2ab7a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_U5otJHt9-IEo3aW4zQRTs

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 sys84-ink-agent-checkout-x402-payment-session-initiator-4af2ab7a -d '<json body>'
```

Example prompt: Create an x402 checkout session for product 'ink-analysis-v1' charging 0.002 USDC, with my merchant wallet 0xABC123... as the recipient and the description 'Ink chain risk report'.

## When to prefer this

Choose this endpoint when you need to programmatically generate an x402-compliant payment session for micropayment-gated API access, especially when your agent or service needs to produce a 402 Payment Required response with encoded payment requirements. Prefer this over generic payment APIs when the consuming agent speaks the x402 protocol and you need USDC-denominated per-call billing with settlement and verification URL pairs.

## Known failure modes

- Missing required 'product_id' or 'amount_usdc' — returns 400 with validation error
- Invalid or malformed merchant wallet address in 'pay_to' — may cause settlement routing failure
- Network or chain-layer unavailability — returns 5xx with no checkout session created
- Zero or negative USDC amount — rejected as invalid pricing
- Malformed resource URL — may return 400 or produce an uncallable settle URL

## How this service works

Receipt-backed token, wallet, NFT and launch intelligence for humans and agents.

## Output

Returns a JSON object containing a UUID checkout_id, a settle_url for finalizing the payment, a verify_url to confirm payment status, a payment_requirements object conforming to x402 version 2, and a base64-encoded payment_required_header string suitable for inclusion in HTTP 402 responses.

## 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": {
    "body": {
     "type": "object",
     "properties": {
      "pay_to": {
       "type": "string",
       "description": "string optional merchant wallet, defaults to SYS84 wallet"
      },
      "resource": {
       "type": "string",
       "description": "string optional paid resource URL"
      },
      "product_id": {
       "type": "string",
       "description": "string product or service id"
      },
      "amount_usdc": {
       "type": "number",
       "description": "number price to charge in USDC"
      },
      "description": {
       "type": "string",
       "description": "string optional checkout description"
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "POST",
      "PUT",
      "PATCH",
      "DELETE",
      "HEAD"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "pay_to": {
       "type": "string",
       "description": "string optional merchant wallet, defaults to SYS84 wallet"
      },
      "resource": {
       "type": "string",
       "description": "string optional paid resource URL"
      },
      "product_id": {
       "type": "string",
       "description": "string product or service id"
      },
      "amount_usdc": {
       "type": "number",
       "description": "number price to charge in USDC"
      },
      "description": {
       "type": "string",
       "description": "string optional checkout description"
      }
     }
    }
   }
  },
  "output": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "settle_url": {
       "type": "string",
       "description": "string facilitator settle URL"
      },
      "verify_url": {
       "type": "string",
       "description": "string facilitator verify URL"
      },
      "checkout_id": {
       "type": "string",
       "description": "string uuid"
      },
      "payment_requirements": {
       "type": "object",
       "description": "object x402Version 2 requirements"
      },
      "payment_r
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "settle_url": "string",
  "verify_url": "string",
  "checkout_id": "string",
  "payment_requirements": {},
  "payment_required_header": "string"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/sys84-ink-agent-checkout-x402-payment-session-initiator-4af2ab7a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.sys84.org](https://www.zero.xyz/host/api.sys84.org/llms.txt)