# Synapse API — Monad RPC Endpoint

> Synapse API — Monad 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 2026-10-15).

Proxies JSON-RPC calls to the Monad blockchain network, enabling agents to query chain state, send transactions, and interact with Monad smart contracts.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/monad/rpc?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-monad-rpc-endpoint-bd1cfab6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_SQKRQHMoTXH8BuQ-IlSAl

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-monad-rpc-endpoint-bd1cfab6 -d '<json body>'
```

Example prompt: Call eth_getBalance on the Monad network for wallet address 0xAbC123... and tell me the current balance in wei.

## When to prefer this

Choose this endpoint when you specifically need to interact with the Monad blockchain via JSON-RPC and want pay-per-call pricing without managing your own node. Prefer over self-hosted nodes when you need low-setup Monad access with USDC micropayments via x402.

## Known failure modes

- Invalid RPC method name returns JSON-RPC error with code -32601
- Malformed params array causes parse error -32700
- Network congestion or Monad node unavailability returns 503 or timeout
- Payment failure (insufficient USDC) blocks the call before it reaches the RPC layer
- Calling a non-existent contract address returns null result without 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 the 'result' field with the requested blockchain data (e.g. balance in hex wei, block number, transaction receipt object, or contract return data), or an 'error' object with code and message if the call fails.

## 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-monad-rpc-endpoint-bd1cfab6/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)