# Synapse API — Sonic RPC Endpoint

> Synapse API — Sonic 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 a JSON-RPC interface to the Sonic blockchain network, enabling read and write interactions with Sonic chain data via pay-per-call micropayments.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/sonic/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-sonic-rpc-endpoint-b9d18639
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UhiHQPORMMsNUEW8hE8m5

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-sonic-rpc-endpoint-b9d18639 -d '<json body>'
```

Example prompt: Can you call eth_getBalance on the Sonic blockchain for address 0xABC123... using the Sonic RPC endpoint?

## When to prefer this

Choose this endpoint when you need direct JSON-RPC access to the Sonic blockchain network specifically, and you want pay-per-call micropayment billing via x402 rather than managing a subscription or API key. Prefer it over generic multi-chain RPC providers when Sonic-native access and per-call USDC payments are acceptable.

## Known failure modes

- Invalid RPC method name returns JSON-RPC error -32601 (Method not found)
- Malformed params array causes -32602 (Invalid params)
- Payment failure or insufficient USDC returns HTTP 402
- Network congestion or Sonic node unavailability returns timeout or 503
- Calling write methods without a valid signed transaction returns execution error

## 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

A standard JSON-RPC response object containing either a 'result' field with the requested blockchain data (balance, block info, transaction receipt, etc.) or an 'error' field describing what went wrong. The exact shape depends on the RPC 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-sonic-rpc-endpoint-b9d18639/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)