# HALOWERK kettenwerk — Transaction Decoder

> HALOWERK kettenwerk — Transaction Decoder is a paid API for AI agents from kette.netzhandwerker.de, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-15).

Decodes Ethereum-compatible transaction call data, signed raw transactions, and receipt logs into human-readable form without broadcasting anything to the network.

## Facts

- Endpoint: POST https://kette.netzhandwerker.de/tx/decode
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-kettenwerk-transaction-decoder-d0a04afd
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UKT9IFnN8Thriza4ozqLn

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 halowerk-kettenwerk-transaction-decoder-d0a04afd -d '<json body>'
```

Example prompt: Can you decode this raw signed Ethereum transaction for me — 0x02f8... — on Base, so I can see what function it's calling and what the parameters are before I decide to broadcast it?

## When to prefer this

Choose this endpoint when you need to decode EVM transaction calldata or raw signed transactions offline (no broadcast) across Ethereum, Base, Arbitrum, Optimism, Polygon, or BSC. It is particularly useful for pre-flight inspection before signing, debugging failed transactions, or auditing unfamiliar calldata. Prefer it over a block explorer when you need programmatic, structured output rather than a web UI, or when decoding unsigned/unsigned raw transactions that aren't on-chain yet.

## Known failure modes

- Unknown ABI / selector not in database — function name may not be resolvable, returns raw selector only
- Invalid hex format — returns 400 if calldata or raw tx doesn't match expected pattern
- Unrecognized chain — must be one of the six supported enum values
- Transaction hash not yet mined — logs cannot be decoded for pending transactions
- Malformed input — if neither raw, data+to, nor tx_hash is provided the request is ambiguous
- Payment failure — x402 USDC payment on Base Mainnet required, rejected if not provided

## How this service works

HALOWERK kettenwerk — bezahlte Endpunkte nach x402. Preise in USDC auf Base Mainnet.

## Output

Returns a structured breakdown of the transaction including the decoded function name, input parameter names and values, decoded ABI selector, and (when a tx_hash is provided for a mined transaction) decoded receipt event logs — all in human-readable form. The transaction is never broadcast.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "to": {
   "type": "string",
   "pattern": "^0x[0-9a-fA-F]{40}$",
   "description": "Target address, when passing call data directly."
  },
  "raw": {
   "type": "string",
   "pattern": "^0x[0-9a-fA-F]{20,}$",
   "description": "Raw signed transaction (any EIP-2718 type). It is only parsed, never broadcast."
  },
  "data": {
   "type": "string",
   "pattern": "^0x[0-9a-fA-F]*$",
   "description": "Call data, when passing it directly."
  },
  "chain": {
   "enum": [
    "ethereum",
    "base",
    "arbitrum",
    "optimism",
    "polygon",
    "bsc"
   ],
   "type": "string",
   "description": "Chain the call belongs to."
  },
  "value": {
   "type": "string",
   "description": "Value in wei as a decimal or 0x string. Optional, defaults to 0."
  },
  "tx_hash": {
   "type": "string",
   "pattern": "^0x[0-9a-fA-F]{64}$",
   "description": "Hash of an existing transaction. Its receipt logs are decoded too when it is mined."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/halowerk-kettenwerk-transaction-decoder-d0a04afd/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from kette.netzhandwerker.de](https://www.zero.xyz/host/kette.netzhandwerker.de/llms.txt)