# `MPP.Methods.Tempo.Proof`
[🔗](https://github.com/ZenHive/mpp/blob/v0.10.0/lib/mpp/methods/tempo/proof.ex#L1)

EIP-712 proof credentials for zero-amount Tempo charge flows.

Wallet-bound MPP domain version `3`: the signed `account` field binds the
proof to a specific payer so it cannot be replayed against another wallet for
the same challenge. Matches `refs/mppx/src/tempo/internal/proof.ts`.

# `params`

```elixir
@type params() :: %{
  account: String.t(),
  chain_id: non_neg_integer(),
  challenge_id: String.t(),
  realm: String.t()
}
```

# `hash`

```elixir
@spec hash(params()) :: <<_::256>>
```

Compute the EIP-712 signing digest (32-byte binary) for a proof credential.

# `recover_authorized_proof_signer`

```elixir
@spec recover_authorized_proof_signer(params(), String.t(), String.t()) ::
  {:ok, String.t()} | {:error, String.t()}
```

Recover the authorized access-key signer when direct wallet verification fails.

Matches `recoverAuthorizedProofSigner` in `refs/mppx/src/tempo/server/Charge.ts`.
Returns `{:ok, access_key_address}` or `{:error, reason}`.

# `typed_data`

```elixir
@spec typed_data(params()) :: Cartouche.Typed.t()
```

Build the EIP-712 typed-data map for a Tempo proof credential.

# `verify_signature`

```elixir
@spec verify_signature(params(), String.t(), String.t()) :: :ok | {:error, String.t()}
```

Verify a proof signature recovers to `expected_account`.

Returns `:ok` or `{:error, reason}`.

---

*Consult [api-reference.md](api-reference.md) for complete listing*