# Synapse API — Metis Token Balances

> Synapse API — Metis 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).

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

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/metis/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-metis-token-balances-924faa53
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WvIht2tQYM-ES10gU8n0r

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-metis-token-balances-924faa53 -d '<json body>'
```

Example prompt: Can you check what token balances the wallet 0x1234...abcd holds on the Metis network, specifically for the contracts 0xDeadBeef... and 0xCafe...?

## When to prefer this

Use this endpoint when you specifically need token balance data on the Metis blockchain network. It is ideal for DeFi portfolio tracking, post-transfer verification, and multi-token position monitoring on Metis. Prefer this over general multi-chain endpoints when Metis-specific balance resolution is required, and when you need to optionally filter by specific contract addresses.

## Known failure modes

- Invalid or malformed owner address returns an error or empty result
- Unrecognized or non-existent contract addresses yield zero balances or errors
- Network downtime on Metis may cause lookup failures
- Rate limiting or payment failure via x402 protocol blocks the request
- Wallet with no token holdings returns an empty balance list

## 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 Metis network, including token contract addresses and corresponding amounts held, optionally scoped to specified contract addresses.

## 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-metis-token-balances-924faa53/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)