# x402-gateway: wallet_verify_siwe

> x402-gateway: wallet_verify_siwe is a paid API for AI agents from x402.freeq.one, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-11).

Verify a Sign-In-With-Ethereum (EIP-4361) SIWE signature, returning the recovered wallet address and chainId without creating sessions or consuming nonces.

## Facts

- Endpoint: POST https://x402.freeq.one/tools/wallet_verify_siwe?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-gateway-wallet-verify-siwe-0276ee47
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Lkr0zrchoK9yF4ATSdPKt

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 x402-gateway-wallet-verify-siwe-0276ee47 -d '<json body>'
```

Example prompt: Can you verify this SIWE signature for me? The message is the EIP-4361 string my frontend generated and the signature is the hex string the user's wallet returned — I just need to know which wallet address signed it and on which chain, without creating any session.

## When to prefer this

Choose this endpoint when you need stateless, cryptographic verification of a Sign-In-With-Ethereum (EIP-4361) signature without any server-side session management or nonce tracking. It is ideal for agents that need to confirm wallet ownership as part of an authentication flow, audit past signatures, or verify identity claims in a trustless manner. Prefer it over full auth servers when you want a pure oracle that simply recovers the signer address without side effects.

## Known failure modes

- Invalid or malformed SIWE message format — returns error indicating EIP-4361 parse failure
- Signature does not match the message — returns error with mismatch indication
- Unsupported chainId or network — may return validation error
- Malformed hex signature string — returns parse or decoding error
- Missing required body fields — returns schema validation error
- Payment not provided or insufficient — returns HTTP 402

## How this service works

SIWE Signature Verifier: Verify a Sign-In-With-Ethereum (EIP-4361) signature. Stateless oracle: checks the signature against the message and returns the wallet address + chainId. Never mints sessions or consumes nonces. Get a checksummed address first via wallet_checksum. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/wallet_verify_siwe.

## Output

Returns the EIP-55 checksummed Ethereum wallet address that produced the signature, along with the chainId extracted from the SIWE message. The check is purely cryptographic and stateless — no session is created, no nonce is consumed, and the result is deterministic given the same inputs.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "message": {
   "type": "string",
   "description": "EIP-4361 SIWE message (line 2 must be a checksummed address)"
  },
  "signature": {
   "type": "string",
   "description": "0x-prefixed personal_sign signature over the exact message bytes"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {}
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-gateway-wallet-verify-siwe-0276ee47/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.freeq.one](https://www.zero.xyz/host/x402.freeq.one/llms.txt)