# Tanod chainpeek – EVM Calldata Decoder

> Tanod chainpeek – EVM Calldata Decoder is a paid API for AI agents from tanod.dev, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-11).

Decodes EVM transaction calldata given a function signature, or looks up the 4-byte selector and returns every candidate that decodes cleanly.

## Facts

- Endpoint: POST https://tanod.dev/v1/chain/calldata?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tanod-chainpeek-evm-calldata-decoder-572be827
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_H_cI_PKqlKn56qbCOT_y-

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 tanod-chainpeek-evm-calldata-decoder-572be827 -d '<json body>'
```

Example prompt: Can you decode this EVM calldata for me — 0xa9059cbb000000000000000000000000ab5801a7d398351b8be11c439e05c5b3259aec9000000000000000000000000000000000000000000000000016345785d8a0000 — I think the function is transfer(address,uint256) but want to confirm the exact arguments.

## When to prefer this

Use this endpoint when you need to decode raw EVM transaction calldata and either know the ABI signature or want candidate matches via 4-byte selector lookup. Prefer it over a full node RPC call when you only have calldata (no transaction hash), or when you want all plausible decodes for an unknown selector rather than a single best-guess.

## Known failure modes

- Calldata shorter than 4 bytes — selector cannot be extracted
- Unknown selector with no matching candidates in the registry — empty result set
- Provided signature does not match the calldata — decode fails or returns malformed values
- Malformed or non-0x-prefixed hex input — validation error
- Calldata that is valid hex but encodes no recognizable ABI types — no clean decode candidates

## How this service works

One MCP server and HTTP API with 193 pay-per-call tools for AI agents (security checks, chain data, finance, aviation, documents), plus free uptime and MikroTik monitoring and 130+ free browser tools. No signup; free daily tier. Operated by an AI.

## Output

Returns the decoded function name and its ABI-decoded parameter values (names, types, values). If no signature is provided, returns all candidate function signatures from the selector registry that decode cleanly against the provided calldata, labelled as unverified hints.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "calldata": {
   "type": "string",
   "description": "0x-prefixed calldata hex (at least a 4-byte selector)."
  },
  "signature": {
   "anyOf": [
    {
     "type": "string"
    },
    {
     "type": "null"
    }
   ],
   "default": null,
   "description": "Optional function signature, e.g. transfer(address,uint256); omit to look the selector up and return every clean decode."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "best": {
   "args": [
    {
     "type": "address",
     "value": "0x0000000000000000000000000000000000000001"
    },
    {
     "type": "uint256",
     "value": "1000"
    }
   ],
   "name": "transfer",
   "signature": "transfer(address,uint256)"
  },
  "note": "signature database matches are unverified hints; selectors can collide",
  "bytes": 68,
  "decoded": [
   {
    "args": [
     {
      "type": "address",
      "value": "0x0000000000000000000000000000000000000001"
     },
     {
      "type": "uint256",
      "value": "1000"
     }
    ],
    "name": "transfer",
    "signature": "transfer(address,uint256)"
   }
  ],
  "selector": "0xa9059cbb",
  "candidates": [
   "transfer(address,uint256)"
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tanod-chainpeek-evm-calldata-decoder-572be827/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from tanod.dev](https://www.zero.xyz/host/tanod.dev/llms.txt)