# Synapse API — opBNB RPC Endpoint

> Synapse API — opBNB RPC Endpoint is a paid API for AI agents from synapse-api-brown.vercel.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Provides JSON-RPC access to the opBNB blockchain network, enabling on-chain data queries and transaction submission via pay-per-call.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/opbnb/rpc
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-opbnb-rpc-endpoint-56607642
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1Uy__N8Ld8qQq-H7MvSiM

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 synapse-api-opbnb-rpc-endpoint-56607642 -d '<json body>'
```

Example prompt: Call the opBNB RPC endpoint using eth_getBalance to check the balance of wallet address 0xAbC123... on the latest block.

## When to prefer this

Use this endpoint when you need pay-per-call, no-subscription access to the opBNB (BNB Layer 2) blockchain RPC without managing your own node. Prefer it over self-hosted nodes when cost-per-call economics are favorable and you need quick access to opBNB-specific chain data.

## Known failure modes

- Invalid RPC method name returns JSON-RPC error code -32601
- Malformed params array causes parse error -32700
- Network downtime or Vercel cold start may cause timeout
- Unsupported opBNB-specific methods may return method not found
- Payment failure via x402 protocol blocks request execution

## How this service works

High-speed API suite for AI processing, web scraping, and smart data utilities across 57+ blockchain networks. Pay-per-call via x402.

## Output

Returns a standard JSON-RPC response object containing the result of the requested RPC method, such as account balance, block details, transaction receipts, or contract return values, depending on the method called.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "method": {
   "type": "string"
  },
  "params": {
   "type": "array",
   "items": {}
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synapse-api-opbnb-rpc-endpoint-56607642/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from synapse-api-brown.vercel.app](https://www.zero.xyz/host/synapse-api-brown.vercel.app/llms.txt)