# Synapse API — Citrea Token Balances

> Synapse API — Citrea 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 2026-09-16).

Fetches ERC-20 token balances for a given wallet address on the Citrea blockchain network, optionally filtered by specific contract addresses.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/citrea/token/balances
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-citrea-token-balances-feb0ac44
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_pc8v6hz1fwjXz0RE33XeD

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-citrea-token-balances-feb0ac44 -d '<json body>'
```

Example prompt: What ERC-20 token balances does the Citrea wallet 0xAbC123... hold? Check specifically for the tokens at contract addresses 0xDef456... and 0xGhi789....

## When to prefer this

Use this endpoint when you specifically need token balance data on the Citrea network (Bitcoin ZK-rollup). It is pay-per-call via x402 USDC micropayments, making it suitable for on-demand balance lookups without subscription overhead. Prefer this over general multi-chain balance APIs when Citrea is the target network and you need lightweight, fast balance queries.

## Known failure modes

- Invalid or malformed owner wallet address returns an error or empty result
- Contract addresses array contains invalid addresses, leading to partial or no results
- Citrea network RPC unavailability causes timeout or service error
- Address with no token holdings returns an empty balances array
- Rate limiting or payment failure (x402) prevents the call from completing

## 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 ERC-20 token balances associated with the provided owner address on the Citrea 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-citrea-token-balances-feb0ac44/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)