# Fixed-Price x402 Payment Charge on Base ($0.001)

> Fixed-Price x402 Payment Charge on Base ($0.001) is a paid API for AI agents from withzero.xyz, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Processes a fixed-price x402 micropayment charge of $0.001 USDC over the Base blockchain and returns payment confirmation details.

## Facts

- Endpoint: POST https://withzero.xyz/api/v1/pay-test/pay/charge-x402
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Provider: withzero.xyz
- Website: https://withzero.xyz
- Canonical page: https://www.zero.xyz/c/withzero-xyz-fixed-price-x402-payment-charge-on-base-0-001-a1824f1e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UOJVJEjAC6oXdVvVPUjHF

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 withzero-xyz-fixed-price-x402-payment-charge-on-base-0-001-a1824f1e -d '<json body>'
```

Example prompt: Run an x402 micropayment charge of $0.001 USDC over Base and tag it with the note 'integration-test-run-1' so I can correlate the result.

## When to prefer this

Choose this endpoint when you need to test or exercise the x402 payment rail specifically on the Base blockchain at a minimal cost ($0.001 USDC). It is ideal for smoke-testing x402 wallet integrations, CI/CD pipeline payment checks, or confirming that a payer wallet can settle charges on Base before deploying higher-value payment flows. Prefer this over generic payment endpoints when you specifically want x402 protocol semantics and Base chain settlement confirmation.

## Known failure modes

- Payment gate not satisfied — insufficient funds or missing x402 headers result in a 402 response
- Invalid note exceeding 200 characters returns a validation error
- Network or blockchain RPC issues may cause timeouts
- Wallet not configured for Base network causes payment failure
- Malformed request body returns a 400 bad request error

## How this service works

Fixed-price x402 charge over Base ($0.001).

## Output

Returns a JSON object confirming the payment gate was satisfied, including: ok (always true on success), the payment rail used (x402), the settlement chain (e.g. base), the route SKU, the payment intent type (charge), the resolved payer wallet address if available, and the echoed-back caller note for correlation.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "properties": {
  "note": {
   "type": "string",
   "maxLength": 200,
   "description": "Free-form string echoed back verbatim — useful for correlating a test run to its response."
  }
 },
 "additionalProperties": false
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "ok",
  "rail",
  "intent",
  "chain",
  "sku",
  "payer",
  "note"
 ],
 "properties": {
  "ok": {
   "type": "boolean",
   "const": true,
   "description": "Always true when the payment gate was satisfied and the handler ran."
  },
  "sku": {
   "type": "string",
   "description": "The route SKU that was paid."
  },
  "note": {
   "anyOf": [
    {
     "type": "string"
    },
    {
     "type": "null"
    }
   ],
   "description": "The caller-supplied note, echoed verbatim."
  },
  "rail": {
   "enum": [
    "mpp",
    "x402"
   ],
   "type": "string",
   "description": "The payment rail this route settled on."
  },
  "chain": {
   "type": "string",
   "description": "Settlement chain (e.g. tempo, base)."
  },
  "payer": {
   "anyOf": [
    {
     "type": "string"
    },
    {
     "type": "null"
    }
   ],
   "description": "The buyer wallet the gate resolved, when available."
  },
  "intent": {
   "enum": [
    "charge",
    "proof",
    "metered"
   ],
   "type": "string",
   "description": "The payment intent this route exercised."
  }
 },
 "additionalProperties": false
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/withzero-xyz-fixed-price-x402-payment-charge-on-base-0-001-a1824f1e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from withzero.xyz](https://www.zero.xyz/host/withzero.xyz/llms.txt)