# Synapse API — opBNB Token Balances

> Synapse API — opBNB 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 2026-09-15).

Retrieves token balances for a given wallet address on the opBNB blockchain network, optionally filtered by specific contract addresses.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/opbnb/token/balances
- 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-token-balances-d9a4d2a9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8JP6x7AX-iKW8zAkm5Lz7

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-token-balances-d9a4d2a9 -d '<json body>'
```

Example prompt: What are all the token balances for wallet 0xABC123...def on opBNB? Also check the balances for these two contracts: 0xToken1... and 0xToken2....

## When to prefer this

Use this endpoint when you need to query token balances specifically on the opBNB (Optimistic BNB) Layer 2 network. Prefer this over generic multi-chain balance endpoints when your use case is opBNB-specific and you want pay-per-call pricing without subscription overhead.

## Known failure modes

- Invalid or malformed wallet address returns an error or empty result
- Contract address array contains invalid addresses causing partial or failed lookups
- opBNB network outage or RPC unavailability causing timeout
- Wallet address with no token holdings returns empty balance list
- Rate limiting or payment failure via x402 protocol returning 402 status

## 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 associated with the given wallet address on the opBNB network, including token contract addresses and their corresponding balance amounts. If specific contract addresses are provided, results are filtered to those tokens only.

## 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-opbnb-token-balances-d9a4d2a9/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)