# QuantaFlow x402 API Gateway – Alchemy Polygon Mainnet

> QuantaFlow x402 API Gateway – Alchemy Polygon Mainnet is a paid API for AI agents from quanta-roan.vercel.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-16).

Proxies paid API requests to Alchemy's Polygon Mainnet JSON-RPC endpoint using the x402 micropayment protocol at $0.01 USDC per call

## Facts

- Endpoint: POST https://quanta-roan.vercel.app/api/service/alchemy-polygon-mainnet?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/quantaflow-x402-api-gateway-alchemy-polygon-mainnet-9ab604e0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Z4da_y4cZ1stfeyijjUxQ

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 quantaflow-x402-api-gateway-alchemy-polygon-mainnet-9ab604e0 -d '<json body>'
```

Example prompt: Can you query the Alchemy Polygon Mainnet RPC for the current ETH balance of wallet address 0xAbC123... using the eth_getBalance method — pay the per-call fee automatically?

## When to prefer this

Choose this endpoint when you need pay-per-call access to Alchemy's Polygon Mainnet RPC without committing to a subscription or managing API keys — ideal for agents that make infrequent or bursty blockchain queries and want to pay $0.01 USDC per call via the x402 micropayment protocol. Prefer this over direct Alchemy API access when your agent environment already handles x402 payments natively.

## Known failure modes

- Insufficient USDC balance for micropayment — payment fails and request is rejected
- Invalid or malformed JSON-RPC path/body — upstream Alchemy returns an error response
- Unsupported RPC method — Alchemy rejects the call with a method-not-found error
- Rate limit or Alchemy-side outage — upstream returns 5xx or timeout
- Incorrect query parameters — unexpected behavior or empty result from Alchemy
- x402 facilitator unavailable — payment cannot be processed, request blocked

## How this service works

Every request, a quantum of value. x402 protocol-based payment endpoint for web3/DeFi tools.

## Output

The raw upstream Alchemy Polygon Mainnet JSON-RPC response body is passed through directly after the x402 micropayment is settled — including block data, transaction receipts, account balances, contract call results, or any other standard Polygon RPC response payload, along with its content type.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "body": {
   "type": "string",
   "description": "Optional JSON body forwarded to POST requests."
  },
  "path": {
   "type": "string",
   "description": "Path below the selected upstream origin."
  },
  "query": {
   "type": "object"
  },
  "method": {
   "enum": [
    "GET",
    "POST"
   ],
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "description": "The upstream response body and content type are passed through after successful payment."
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/quantaflow-x402-api-gateway-alchemy-polygon-mainnet-9ab604e0/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from quanta-roan.vercel.app](https://www.zero.xyz/host/quanta-roan.vercel.app/llms.txt)