# Synapse API — ZKsync Transaction History

> Synapse API — ZKsync Transaction History 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 paginated transaction history for addresses on the ZKsync blockchain network with filtering by block range, category, and address.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/zksync/tx/history
- 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-zksync-transaction-history-e8cb8c27
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HiXE5fcnWuXwkL3kDu_mi

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-zksync-transaction-history-e8cb8c27 -d '<json body>'
```

Example prompt: Pull the last 25 ZKsync transactions sent from wallet 0xAbC...123 to 0xDeF...456, in descending order, including token metadata and skipping zero-value transfers.

## When to prefer this

Use this endpoint when you need paginated ZKsync-specific transaction history with fine-grained filtering by sender, recipient, block range, and asset category. Prefer this over generic multi-chain endpoints when you specifically need ZKsync L2 transaction data with per-call pay-as-you-go pricing at $0.01 USDC.

## Known failure modes

- Invalid address format returns a 400 error
- Invalid block range (fromBlock > toBlock) may return empty results or an error
- Expired or invalid pageKey causes pagination to restart or fail
- Unsupported category values may return empty results
- Payment not received (402) if x402 micropayment is not included
- Rate limiting or service unavailability returns 5xx errors

## 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 ZKsync transactions matching the specified filters, including transfer details such as asset type, value, sender, recipient, block number, and optionally token metadata. A pageKey is typically included to fetch the next page of results.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "order": {
   "enum": [
    "asc",
    "desc"
   ],
   "type": "string"
  },
  "pageKey": {
   "type": "string"
  },
  "toBlock": {
   "type": "string"
  },
  "category": {
   "type": "array",
   "items": {
    "type": "string"
   }
  },
  "maxCount": {
   "type": "number"
  },
  "fromBlock": {
   "type": "string"
  },
  "toAddress": {
   "type": "string"
  },
  "fromAddress": {
   "type": "string"
  },
  "withMetadata": {
   "type": "boolean"
  },
  "excludeZeroValue": {
   "type": "boolean"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synapse-api-zksync-transaction-history-e8cb8c27/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)