# QuantaFlow x402 API Gateway — Alchemy Optimism Mainnet

> QuantaFlow x402 API Gateway — Alchemy Optimism 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 2026-10-18).

Proxies requests to Alchemy's Optimism Mainnet RPC/API through an x402 micropayment-gated gateway, charging $0.01 USDC per call.

## Facts

- Endpoint: POST https://quanta-roan.vercel.app/api/service/alchemy-opt-mainnet?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/quantaflow-x402-api-gateway-alchemy-optimism-mainnet-19fdfc9b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_SapzfsV5RDpWRxl_nIofy

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-optimism-mainnet-19fdfc9b -d '<json body>'
```

Example prompt: Fetch the latest block number and gas price on Optimism Mainnet through the QuantaFlow Alchemy gateway — use the /v2 path with an eth_blockNumber JSON-RPC call.

## When to prefer this

Choose this endpoint when you need pay-per-use access to Alchemy's Optimism Mainnet APIs without committing to a subscription or managing API keys. Ideal for low-frequency or agent-driven queries where per-call micropayment ($0.01 USDC via x402) is preferable to a monthly plan. Best suited for agents already operating in the x402 payment ecosystem querying Optimism L2 on-chain data.

## Known failure modes

- Payment failure: insufficient USDC balance or x402 payment not included — gateway returns 402 Payment Required
- Invalid path: unrecognized or malformed Alchemy API path — upstream returns 404 or 400
- Invalid JSON-RPC method: Alchemy returns an error object with code and message
- Rate limiting: Alchemy upstream rate limit exceeded — returns 429
- Network error: Optimism Mainnet node unavailable — returns 503 or timeout
- Malformed request body: JSON parse error forwarded from upstream

## How this service works

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

## Output

The raw upstream response from Alchemy's Optimism Mainnet API is passed through directly, including the JSON-RPC result body and content type. Typical responses include blockchain data such as block info, transaction receipts, token balances, contract states, or event logs.

## 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-optimism-mainnet-19fdfc9b/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)