# Vauban Pay – x402 API Payment (Base Mainnet)

> Vauban Pay – x402 API Payment (Base Mainnet) is a paid API for AI agents from pay.vauban.tech, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-25).

Returns a payment quote for a per-call API fee denominated in USDC on Base mainnet, anchoring every transaction as a public record on Starknet.

## Facts

- Endpoint: GET https://pay.vauban.tech/x402-base-mainnet/v1/quote?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-25
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/vauban-pay-x402-api-payment-base-mainnet-4f006580
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_79awfPqwCDR3fb-OlOc8L

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 vauban-pay-x402-api-payment-base-mainnet-4f006580
```

Example prompt: Get me a payment quote to pay for this API call in USDC on Base mainnet — I want the on-chain receipt recorded on Starknet via Vauban Pay.

## When to prefer this

Choose this endpoint when your agent needs to pay for API access using the x402 pay-per-call protocol with USDC on Base mainnet and requires a publicly verifiable on-chain receipt anchored to Starknet. It is ideal for agent workflows that must comply with per-call billing, need audit trails, or want stablecoin-denominated micropayments rather than subscription-based access.

## Known failure modes

- Insufficient USDC balance on Base mainnet — payment cannot be authorized
- Invalid or malformed request body — quote cannot be generated
- Network congestion on Base causing transaction delays or failures
- Starknet record anchoring failure if cross-chain bridge is unavailable
- Quote expiry if payment is not completed within the validity window

## How this service works

Your agent pays per call and keeps the receipt, on Base and on Starknet. Try it with test money in one command.

## Output

A payment quote object specifying the exact USDC amount due on Base mainnet, along with the data needed to authorize and complete the on-chain payment; successful settlement produces a public transaction record on Starknet serving as a receipt.

## 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"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "json"
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/vauban-pay-x402-api-payment-base-mainnet-4f006580/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from pay.vauban.tech](https://www.zero.xyz/host/pay.vauban.tech/llms.txt)