# TraceFast Contract Bytecode

> TraceFast Contract Bytecode is a paid API for AI agents from mpp.tracefast.xyz, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-14).

Returns the live runtime bytecode, code hash, and structural fingerprint of an Ethereum smart contract by address

## Facts

- Endpoint: GET https://mpp.tracefast.xyz/api/v1/chains/1/contracts/:address/bytecode?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tracefast-contract-bytecode-90c94194
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6pwImpYHzbFtWWIHzQn9B

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 tracefast-contract-bytecode-90c94194
```

Example prompt: Can you fetch the current runtime bytecode and code hash for the Ethereum contract at 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 on mainnet?

## When to prefer this

Use this endpoint when you need the live, current runtime bytecode of an Ethereum mainnet contract — especially when you also need the code hash for verification or the structural fingerprint for clone/proxy detection. Prefer this over static datasets when you need real-time accuracy of what is actually deployed on-chain right now.

## Known failure modes

- 404 if address has no deployed bytecode (EOA or undeployed address)
- Invalid address format returns an error (must be 0x-prefixed 40 hex chars)
- Network or payment failure returns non-200 status
- Address with self-destructed contract may return 404 or empty bytecode

## How this service works

TraceFast live Ethereum data: the current runtime bytecode of a contract as hex, with its code hash and a structural fingerprint that is equal across contracts sharing the same logic. Up to 24 576 bytes of code. An address with no indexed code answers 404. Path address: The contract address, `0x`-prefixed, 40 hex characters, any case. Docs: https://docs.tracefast.xyz/api/contract-bytecode.md

## Output

Returns up to 24,576 bytes of hex-encoded runtime bytecode, the keccak256 code hash, and a structural fingerprint that is identical across contracts sharing the same logic (e.g. clones or proxies). Returns 404 if the address has no deployed code.

## Request schema (JSON Schema)

```json
{
 "properties": {
  "input": {
   "required": [
    "method"
   ],
   "properties": {
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tracefast-contract-bytecode-90c94194/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mpp.tracefast.xyz](https://www.zero.xyz/host/mpp.tracefast.xyz/llms.txt)