# Synapse API — Avalanche Token Balances

> Synapse API — Avalanche 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 2026-10-31).

Retrieves ERC-20 and native token balances for a given wallet address on the Avalanche blockchain network

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/avalanche/token/balances?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-avalanche-token-balances-d8f6d984
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_NetGR5diZQCzK2SbC9vaI

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-avalanche-token-balances-d8f6d984 -d '<json body>'
```

Example prompt: What are all the token balances for Avalanche wallet 0x1234abcd...efgh? Also check the balance for contract addresses 0xTokenA and 0xTokenB.

## When to prefer this

Choose this endpoint when you specifically need token balance data on the Avalanche (AVAX) network and want a pay-per-call model without API key subscription overhead. Prefer this over general multi-chain APIs when Avalanche is the target chain and you need quick, lightweight balance lookups rather than full transaction history.

## Known failure modes

- Invalid owner address format returns an error or empty result
- Unknown or invalid contract address returns zero balance or error
- Rate limiting or network timeouts if Avalanche RPC is slow
- Empty response if wallet holds none of the specified tokens
- Payment failure via x402 if USDC balance is insufficient

## 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 specified owner wallet address on the Avalanche network, including per-contract token amounts and potentially token metadata such as symbol and decimals for each contract address provided.

## 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-avalanche-token-balances-d8f6d984/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)