# Synapse API — NFT Metadata Lookup

> Synapse API — 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 2026-10-17).

Retrieves metadata for a specific NFT given its contract address and token ID across blockchain networks

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/abstract/nft/metadata?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-nft-metadata-lookup-36026fd4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Oc49l64xSWl3_JOKlGZfo

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-metadata-lookup-36026fd4 -d '<json body>'
```

Example prompt: Can you pull the metadata for NFT token ID 1234 from contract address 0xBC4CA0EdA7647A8aB7C2061c2E118A18a936f13D — I want to see its traits and image.

## When to prefer this

Choose this endpoint when you need rapid NFT metadata retrieval across a wide range of blockchains (57+) at a low per-call cost of $0.01 USDC via x402 micropayment. Ideal for agents that need on-demand NFT data without maintaining their own indexer or RPC infrastructure.

## Known failure modes

- Invalid or non-existent contract address returns an error or empty response
- Token ID not found or not yet minted returns a 404 or null metadata
- Metadata hosted on unreachable IPFS/arweave gateway causes timeout
- Contract is not an ERC-721/ERC-1155 standard and lacks a tokenURI function
- Network not supported among the 57+ chains returns an unsupported network error
- Payment not included or insufficient USDC causes 402 payment required response

## 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 structured NFT metadata including token name, description, image URI, external URL, and an array of trait attributes (trait_type, value pairs) as stored in or referenced by the 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-nft-metadata-lookup-36026fd4/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)