# EVM ABI Encode/Decode

> EVM ABI Encode/Decode is a paid API for AI agents from webtools402.176-109-107-191.sslip.io, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-14).

ABI-encodes a function call (selector + arguments) or encodes/decodes arbitrary ABI types to build and parse EVM calldata

## Facts

- Endpoint: POST https://webtools402.176-109-107-191.sslip.io/crypto/abi
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/evm-abi-encode-decode-caf5e57d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_5CKn6sOj4q5sEhY3CcUkg

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 evm-abi-encode-decode-caf5e57d -d '<json body>'
```

Example prompt: ABI-encode a call to the transfer(address,uint256) function with recipient 0xAbCd...1234 and amount 1000000000000000000 — give me the full hex calldata including the 4-byte selector.

## When to prefer this

Use this endpoint when an agent needs to construct raw EVM calldata for a smart contract function call without a full web3 library, or when decoding arbitrary ABI-encoded bytes from on-chain transactions. Prefer this over manual encoding when correctness of selector computation and type packing is critical and you don't want to run local code.

## Known failure modes

- Invalid function signature format causes encoding failure
- Mismatched types array and args array length returns an error
- Malformed or truncated hex calldata for decode operation fails parsing
- Unsupported or non-standard ABI type strings cause type resolution errors
- Missing required op field returns validation error

## How this service works

ABI-encode a function call (selector + args) or encode/decode arbitrary ABI types — build and parse EVM calldata correctly.

## Output

Returns ABI-encoded hex calldata for encode_call/encode operations (including the 4-byte function selector for encode_call), or decoded argument values and their types for decode operations — ready to use in raw EVM transactions or for parsing on-chain data.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "op": {
   "enum": [
    "encode_call",
    "encode",
    "decode"
   ],
   "type": "string"
  },
  "args": {
   "type": "array",
   "description": "Argument values for op=encode_call/encode"
  },
  "data": {
   "type": "string",
   "description": "0x calldata/abi bytes for op=decode"
  },
  "types": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "description": "ABI type list for op=encode/decode"
  },
  "signature": {
   "type": "string",
   "description": "Function signature for op=encode_call, e.g. transfer(address,uint256)"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/evm-abi-encode-decode-caf5e57d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from webtools402.176-109-107-191.sslip.io](https://www.zero.xyz/host/webtools402.176-109-107-191.sslip.io/llms.txt)