# Synapse API — Robinhood Token Balances

> Synapse API — Robinhood Token Balances 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 2026-09-13).

Fetches token balances for a given wallet owner across specified ERC-20 contract addresses, likely via Robinhood or an equivalent blockchain data source.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/robinhood/token/balances
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-robinhood-token-balances-a5edf32c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_EBVnWz4SFLhP1RbI5hMLW

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-robinhood-token-balances-a5edf32c -d '<json body>'
```

Example prompt: What are the token balances for wallet 0xAbC123...def for USDC (0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48) and USDT (0xdAC17F958D2ee523a2206206994597C13D831ec7)?

## When to prefer this

Use this endpoint when you need on-chain ERC-20 token balance data for a specific wallet across one or more contract addresses, especially when paying per call via x402 is acceptable and you need fast, targeted balance lookups rather than a full portfolio scan.

## Known failure modes

- Invalid owner address format returns an error or empty result
- Unknown or non-ERC-20 contract addresses return zero balances or errors
- Empty contractAddresses array may return no results or an error
- Network or upstream data provider outage causes lookup failure
- Rate limiting or payment failure (x402) results in 402 response

## 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 list of token balances for the specified wallet owner across the provided ERC-20 contract addresses, including balance amounts per contract.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "owner": {
   "type": "string"
  },
  "contractAddresses": {
   "type": "array",
   "items": {
    "type": "string"
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synapse-api-robinhood-token-balances-a5edf32c/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)