# Synapse API — NFT Holdings by Owner (Sonic Network)

> Synapse API — NFT Holdings by Owner (Sonic Network) 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 2026-10-22).

Returns all NFTs owned by a given wallet address on the Sonic blockchain network, with pagination support.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/sonic/nft/by-owner?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-nft-holdings-by-owner-sonic-network-6d499026
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YpWf2b2YkGOHPXDK2V9qh

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-nft-holdings-by-owner-sonic-network-6d499026 -d '<json body>'
```

Example prompt: Show me all the NFTs owned by wallet 0x1234...abcd on the Sonic blockchain — return up to 20 results.

## When to prefer this

Use this endpoint when you specifically need NFT ownership data on the Sonic blockchain network. It is ideal for building portfolio dashboards, verifying ownership before peer-to-peer trades, or paginating through large NFT collections held by a single wallet. Prefer this over general multi-chain NFT APIs when Sonic network coverage is the explicit requirement.

## Known failure modes

- Invalid or malformed wallet address returns an error or empty result
- Unsupported or non-existent address on Sonic returns an empty NFT list
- Invalid pageKey causes pagination failure or unexpected results
- Rate limit or payment failure (402) if USDC balance is insufficient
- Network or provider timeout resulting in a 500 error

## 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

A list of NFTs owned by the specified wallet address on the Sonic network, including token identifiers and metadata, along with a pagination key for fetching subsequent pages if the result set is large.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "limit": {
   "type": "number"
  },
  "owner": {
   "type": "string"
  },
  "pageKey": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synapse-api-nft-holdings-by-owner-sonic-network-6d499026/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)