# 21.cash Payment Link – 100000 USDC Units

> 21.cash Payment Link – 100000 USDC Units is a paid API for AI agents from api.21.cash, paid per call via x402, $0.1/call, status unknown (last checked 2026-09-14).

Creates or triggers a 21.cash payment link requiring an exact payment of 100000 USDC v2 units (~$0.10) to address 0x8c913b70Db8FAcDAdc37BC2530559DBE879b95b5 on Base (eip155:8453) with a 300-second timeout.

## Facts

- Endpoint: POST https://api.21.cash/api/links/0x8c913b70Db8FAcDAdc37BC2530559DBE879b95b5
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-21-cash-0415e849
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VYS_dp3gJyy2bOYLYHJza

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 api-21-cash-0415e849 -d '<json body>'
```

Example prompt: Send the 21.cash payment link for address 0x8c913b70Db8FAcDAdc37BC2530559DBE879b95b5 — it needs an exact USDC v2 payment of 100000 units on the Base network and the session times out in 5 minutes.

## When to prefer this

Use this endpoint when you need to fulfill a specific 21.cash payment link that requires an exact USDC v2 payment of 100000 units on the Base network. Prefer this over generic crypto transfer endpoints when the recipient address and exact amount are pre-specified by the payment link and you are operating within the x402 payment protocol ecosystem.

## Known failure modes

- Payment amount is not exactly 100000 USDC units — exact amount required
- Transaction not confirmed within 300-second timeout window
- Insufficient USDC v2 balance in payer wallet
- Wrong network used — must be Base (eip155:8453), not Ethereum mainnet or other chains
- Invalid or expired payment link
- USDC v2 contract mismatch (wrong token version)
- Network congestion causing transaction delay beyond timeout

## How this service works

Provides a payment link requiring an exact USD Coin (USDC v2) payment of 100000 to 0x8c91...95b5 on network eip155:8453 with a 300s timeout.

## Output

Returns a response confirming the payment has been received or providing a payment status for the 21.cash link, including any transaction details for the USDC transfer on Base (eip155:8453).

## 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",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "content": {
       "type": "object",
       "properties": {
        "name": {
         "type": "string"
        },
        "amount": {
         "type": "string"
        },
        "chainId": {
         "type": "number"
        },
        "chainName": {
         "type": "string"
        },
        "description": {
         "type": "string"
        },
        "gatedContent": {},
        "routerAddress": {
         "type": "string"
        }
       }
      },
      "message": {
       "type": "string"
      },
      "receipt": {
       "type": "object",
       "properties": {
        "network": {
         "type": "string"
        },
        "transactionHash": {
         "type": "string"
        }
       }
      },
      "success": {
       "type": "boolean"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-21-cash-0415e849/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.21.cash](https://www.zero.xyz/host/api.21.cash/llms.txt)