# Synapse API — Optimism NFT Lookup by Owner

> Synapse API — Optimism NFT Lookup by Owner 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).

Retrieves all NFTs owned by a given wallet address on the Optimism blockchain network.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/optimism/nft/by-owner
- 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-optimism-nft-lookup-by-owner-c5fb7649
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_lLPRvrUF5pd7lGpyKfRFc

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-optimism-nft-lookup-by-owner-c5fb7649 -d '<json body>'
```

Example prompt: Look up all the NFTs owned by the Optimism wallet address 0xAbC1234...5678 and show me up to 20 results.

## When to prefer this

Use this endpoint when you specifically need to enumerate NFTs held by a wallet on the Optimism L2 network. Prefer this over generic Ethereum NFT lookups when the user is working within the Optimism ecosystem. Ideal for portfolio viewers, NFT-gated access checks, and wallet analytics on Optimism.

## Known failure modes

- Invalid or malformed wallet address returns an error or empty result
- Unsupported address format (non-EVM) causes a bad request
- Expired or invalid pageKey causes pagination failure
- Rate limiting or payment failure (x402) blocks the request
- Empty result set if the wallet holds no NFTs on Optimism

## 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 NFT assets owned by the specified wallet on Optimism, including token metadata such as contract address, token ID, name, image, and collection details. Supports pagination via a page key for wallets with large holdings.

## 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-optimism-nft-lookup-by-owner-c5fb7649/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)