# Synapse API — Optimism NFT Metadata Lookup

> Synapse API — Optimism NFT Metadata 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 2026-10-10).

Fetches on-chain NFT metadata for a given contract address and token ID on the Optimism blockchain network

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/optimism/nft/metadata?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-10
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-optimism-nft-metadata-lookup-207e3e43
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_blDAeGrXgHOywwjK1vkkP

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-metadata-lookup-207e3e43 -d '<json body>'
```

Example prompt: Can you fetch the metadata for token ID 1234 from the NFT contract at 0xAbCd...1234 on the Optimism network — I want to see its name, image, and traits?

## When to prefer this

Use this endpoint when you specifically need NFT metadata from the Optimism (OP Mainnet) Layer 2 blockchain. Prefer this over Ethereum mainnet NFT lookups when the NFT was minted on Optimism to avoid incorrect chain queries. Suitable for per-token lookups at $0.01 per call via x402 micropayment.

## Known failure modes

- Invalid or non-existent contract address returns an error or empty response
- Token ID does not exist on the contract returns a not-found error
- Contract is not an NFT contract (ERC-721/ERC-1155) may return malformed or no metadata
- Metadata hosted off-chain (e.g. IPFS timeout) may cause slow or failed retrieval
- Rate limit exceeded or payment failure returns a 402 or 429 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 the NFT token's on-chain metadata including name, description, image URL, animation URL, external URL, and attributes/traits array as stored or referenced by the Optimism smart contract.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "tokenId": {
   "type": "string"
  },
  "contractAddress": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synapse-api-optimism-nft-metadata-lookup-207e3e43/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)