# Vextorium EVM Signature Verifier

> Vextorium EVM Signature Verifier is a paid API for AI agents from api.vextorium.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-20).

Recovers the signer address from an Ethereum personal_sign (EIP-191) or EIP-712 typed data signature, and optionally confirms it matches an expected address.

## Facts

- Endpoint: POST https://api.vextorium.com/verificar-firma-evm-pago?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/vextorium-evm-signature-verifier-e95eed40
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ERD4agVKHxk-a4Ij6y3Ua

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 vextorium-evm-signature-verifier-e95eed40 -d '<json body>'
```

Example prompt: Can you verify this Ethereum signature — the message was 'Hello World', the signature is 0xabc123...def, and I want to confirm it was signed by 0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf?

## When to prefer this

Choose this endpoint when you need fast, local cryptographic verification of Ethereum personal_sign or EIP-712 signatures without needing an Ethereum node connection. Ideal for authenticating users by wallet signature, verifying off-chain signed messages, or confirming signer identity in web3 workflows. Not suitable for EIP-1271 smart contract wallet signatures, which require on-chain calls.

## Known failure modes

- Malformed or invalid signature hex returns an error or null signer
- Missing required 'firma' field causes a validation error
- EIP-1271 contract wallet signatures are not supported and will not match correctly
- Mismatch between message/typed data and signature yields valid:false
- Incorrect EIP-712 domain or types object causes recovery failure

## How this service works

Verify an Ethereum signature: a personal_sign (EIP-191) message or EIP-712 typed data. Recovers the signer address and, if you pass one, confirms it matches. Local computation; EIP-1271 contract wallets are not covered.

## Output

Returns a JSON object with the signature type (e.g. 'EIP-191 personal_sign'), a boolean indicating if the signature is valid, the recovered signer address, the signed hash, and the expected address if one was provided for comparison.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "firma": {
   "type": "string"
  },
  "mensaje": {
   "type": "string"
  },
  "direccion": {
   "type": "string"
  },
  "datos_eip712": {
   "type": "object"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "tipo": "EIP-191 personal_sign",
  "valida": true,
  "firmante": "0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf",
  "hash_firmado": "0x517cc9957090f83459004d4980c16e723e44524c30d84175324025d957b0451a",
  "direccion_esperada": "0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/vextorium-evm-signature-verifier-e95eed40/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.vextorium.com](https://www.zero.xyz/host/api.vextorium.com/llms.txt)