# Synapse API — Unichain NFT by Owner Lookup

> Synapse API — Unichain NFT by Owner Lookup 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 2026-09-14).

Fetches all NFTs owned by a given wallet address on the Unichain blockchain network, with optional pagination.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/unichain/nft/by-owner
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-unichain-nft-by-owner-lookup-957e073a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZSZs0Ibycf1u0o2LEKnlE

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-unichain-nft-by-owner-lookup-957e073a -d '<json body>'
```

Example prompt: Can you pull up all the NFTs owned by wallet address 0xAbC123...def456 on Unichain — show me up to 20 results?

## When to prefer this

Use this endpoint when you specifically need NFT holdings data for a wallet on the Unichain network. Prefer it over generic NFT APIs when your use case is Unichain-native and you need pay-per-call pricing without a subscription commitment. Well-suited for agents that need to check ownership, build portfolio views, or gate access based on Unichain NFT holdings.

## Known failure modes

- Invalid or malformed owner address returns an error or empty result
- Unichain network unavailable causes timeout or 503
- Invalid pageKey causes pagination error or restart from beginning
- Limit value out of acceptable range returns validation error
- No NFTs owned returns an empty list without 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

Returns a paginated list of NFTs owned by the specified wallet address on Unichain, including token IDs, contract addresses, NFT metadata (name, image, attributes), and a pageKey for fetching subsequent pages if more results exist.

## 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-unichain-nft-by-owner-lookup-957e073a/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)