# Synapse API — MegaETH Transaction History

> Synapse API — MegaETH 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 2026-09-16).

Retrieves paginated transaction history for addresses on the MegaETH blockchain network with filtering by block range, category, and address.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/megaeth/tx/history
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-megaeth-transaction-history-d0a23b9a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_IHKi-HS4uqhw8mpcoAuDI

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-megaeth-transaction-history-d0a23b9a -d '<json body>'
```

Example prompt: Pull the last 50 transactions involving wallet 0xABC...123 on MegaETH, ordered from newest to oldest, and include token transfer metadata.

## When to prefer this

Use this endpoint when you specifically need transaction history on the MegaETH blockchain. It is ideal for wallets, portfolio trackers, compliance tools, or DeFi dashboards needing paginated, filterable on-chain history with block-range scoping and category filtering. Prefer this over generic Ethereum endpoints when your target chain is MegaETH.

## Known failure modes

- Invalid address format returns a validation error
- Unsupported category value causes a 400 bad request
- fromBlock greater than toBlock returns an empty result or error
- Expired or invalid pageKey breaks pagination
- Rate limiting or payment failure (x402) returns a 402 response
- MegaETH node unavailability causes a 503 timeout

## 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 transactions matching the specified filters, each including transaction hash, block number, from/to addresses, value, category, and optionally full metadata. A pageKey is returned if more results are available.

## 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-megaeth-transaction-history-d0a23b9a/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)