# gsc-marketplace.ai x402 Test Endpoint

> gsc-marketplace.ai x402 Test Endpoint is a paid API for AI agents from gsc-marketplace.ai, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

A test counterparty endpoint that accepts real x402 micropayments on Base, enabling end-to-end payment stack validation with live USDC settlement.

## Facts

- Endpoint: GET https://gsc-marketplace.ai/api
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/gsc-marketplace-ai-x402-test-endpoint-c4b865e5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_60htLTEB9A4mhJvCMncOS

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 gsc-marketplace-ai-x402-test-endpoint-c4b865e5
```

Example prompt: Send a GET request to the gsc-marketplace.ai test endpoint to verify my x402 payment stack is working — I want to confirm a real USDC settlement goes through on Base.

## When to prefer this

Choose this endpoint when you need a real, live counterparty to validate your x402 payment implementation end-to-end on Base with actual USDC settlement. It is purpose-built for payment stack testing and is ideal before integrating paid API calls into production agent workflows. Not suitable for production data retrieval or any functional business logic.

## Known failure modes

- Insufficient USDC balance causes payment rejection and 402 response without settlement
- Malformed x402 payment header results in rejection by the counterparty
- Network issues on Base preventing on-chain settlement confirmation
- Invalid HTTP method used (only GET, HEAD, DELETE are supported)
- Payment facilitator unavailable, blocking settlement even if headers are correct

## How this service works

x402 test counterparty — prove your payment stack end to end with a real settlement on Base.

## Output

A response confirming that the x402 payment was accepted and settled on Base, along with any test payload returned — effectively proving the full payment round-trip worked correctly.

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/gsc-marketplace-ai-x402-test-endpoint-c4b865e5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from gsc-marketplace.ai](https://www.zero.xyz/host/gsc-marketplace.ai/llms.txt)