# Hergert Synthora Onchain Data API

> Hergert Synthora Onchain Data API is a paid API for AI agents from api.hergertsynthora.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Queries on-chain blockchain data across multiple EVM networks, supporting operations like ENS resolution, transaction lookup, balance checks, contract inspection, and nonce retrieval.

## Facts

- Endpoint: POST https://api.hergertsynthora.com/v1/onchain
- 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/hergert-synthora-onchain-data-api-a7b893b9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_wIurP8pWKk-Os6v8dipo8

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 hergert-synthora-onchain-data-api-a7b893b9 -d '<json body>'
```

Example prompt: Can you resolve the ENS name vitalik.eth to its current Ethereum address using the onchain lookup service?

## When to prefer this

Choose this endpoint when you need lightweight, pay-per-call on-chain data queries across multiple EVM chains (Ethereum, Base, Polygon, Arbitrum, Optimism) without setting up your own RPC infrastructure. It is well-suited for agents that need to resolve ENS names, verify transactions, check balances, or inspect contracts on demand. The x402 micropayment model ($0.05 USDC per call) makes it cost-effective for occasional queries without a subscription.

## Known failure modes

- Invalid or malformed address/hash returns an error result
- ENS name not found returns found:false
- Unsupported chain value returns validation error
- Missing required field for the chosen op (e.g. no hash for receipt) causes a 400-level error
- Network timeout or RPC node unavailability returns a service error
- Payment not received or insufficient USDC causes a 402 rejection

## How this service works

SYNTHORA Onchain Primitives: multichain (Base/Ethereum/Polygon/Arbitrum/Optimism) transaction receipts, tx lookup, wallet nonce, contract/proxy (EIP-1967) detection, ENS resolution, ERC20 + native balances, contract introspection. Deterministic, Ed25519-signed. 0.001 USDC via x402 on Base. First 3 calls FREE per wallet — send header 'X-WALLET: 0x<your Base address>' (no payment); after that 0.001 USDC per call.

## Output

Returns a JSON object with ok:true, the operation name, and a result object containing the query-specific data (e.g. resolved address for ENS, transaction details for receipt/tx, balance as a number, bytecode string, nonce integer, proxy implementation address, or network metadata). Responses are signed with ed25519.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "op": {
   "enum": [
    "ens",
    "receipt",
    "tx",
    "nonce",
    "code",
    "proxy",
    "balance",
    "erc20-balance",
    "contract",
    "network"
   ],
   "type": "string",
   "description": "Operation to perform"
  },
  "hash": {
   "type": "string",
   "description": "Tx hash 0x… (receipt/tx)"
  },
  "name": {
   "type": "string",
   "description": "ENS name e.g. vitalik.eth (ens)"
  },
  "chain": {
   "enum": [
    "base",
    "ethereum",
    "polygon",
    "arbitrum",
    "optimism"
   ],
   "type": "string",
   "description": "Chain (default ethereum)"
  },
  "token": {
   "type": "string",
   "description": "ERC20 token address (erc20-balance)"
  },
  "address": {
   "type": "string",
   "description": "Address 0x… (nonce/code/proxy/balance/contract)"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/hergert-synthora-onchain-data-api-a7b893b9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.hergertsynthora.com](https://www.zero.xyz/host/api.hergertsynthora.com/llms.txt)