# Synapse API — Ethereum NFT Sales Data

> Synapse API — Ethereum NFT Sales Data 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).

Retrieves historical NFT sales transactions on the Ethereum blockchain, filterable by contract address and block range

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/ethereum/nft/sales
- 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-ethereum-nft-sales-data-600be3cf
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_RTmIDwgp5XafSgtVkpkPU

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-ethereum-nft-sales-data-600be3cf -d '<json body>'
```

Example prompt: Pull the last 50 NFT sales for the Ethereum contract 0xBC4CA0EdA7647A8aB7C2061c2E118A18a936f13B in descending order — I want to see the most recent sales first.

## When to prefer this

Use this endpoint when you need structured, filterable historical NFT sales data for a specific Ethereum contract across a defined block range, especially when you need pagination control and ordering. Prefer this over general blockchain explorers when you want programmatic, pay-per-call access without API key setup overhead and when you need block-precise range filtering.

## Known failure modes

- Invalid contract address format returns a validation error
- fromBlock greater than toBlock returns empty results or error
- Exceeding limit bounds may return an error or be clamped
- Unindexed or very recent blocks may return incomplete data
- Network congestion or upstream node issues may cause timeouts
- Contract address with no sales history returns empty array

## 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 sale records on Ethereum matching the query criteria, including transaction details such as sale events, block numbers, and contract-level data, paginated and ordered according to the specified parameters.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "limit": {
   "type": "number"
  },
  "order": {
   "enum": [
    "asc",
    "desc"
   ],
   "type": "string"
  },
  "toBlock": {
   "type": "number"
  },
  "fromBlock": {
   "type": "number"
  },
  "contractAddress": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synapse-api-ethereum-nft-sales-data-600be3cf/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)