---
title: "EIP-7702 Authorization-Tuple Decoder"
method: POST
path: "/v1/tools/decode_eip7702_authorization_tuple"
tags: ["compliance_control", "eip-7702", "account-abstraction", "authorization-tuple", "ecdsa-recovery", "rlp", "crypto-primitive", "mcp:decode_eip7702_authorization_tuple"]
---

# EIP-7702 Authorization-Tuple Decoder

`POST /v1/tools/decode_eip7702_authorization_tuple`

## Request

- Base URL: `https://ainumbers.co`
- URL: `https://ainumbers.co/v1/tools/decode_eip7702_authorization_tuple`
- Auth: none declared

Recomputes the EIP-7702 authorization-tuple hash (keccak256(0x05 || rlp([chain_id, address, nonce])), the 'Set EOA account code' standard live on Ethereum mainnet since the Pectra upgrade, 2025-05-07), recovers the ECDSA signer from a caller-supplied signature, and reports the address the recovered signer is authorizing as its delegate. The node does not apply EIP-2's low-s rule, which EIP-7702 requires. A tuple with s above secp256k1n/2 is skipped by clients, yet still returns AUTHORIZATION_RECOVERED here. The tuple's own `address` field IS the delegate: the code the EOA is pointing itself at. A zero delegate address clears the account's delegation rather than naming a delegate. This node stops at that address -- it never inspects, fetches, or judges the delegate contract's bytecode, and makes no safe/unsafe verdict about it. chain_id = 0 is EIP-7702-defined as a valid, deliberate cross-chain authorization (replayable on any chain) and is reported as such, never treated as malformed input. RLP encoding is hand-authored public-spec arithmetic (Ethereum Yellow Paper Appendix B); keccak256 and secp256k1 recovery come from the already-vendored, pinned noble-curves bundle, no new vendoring. Malformed or incomplete input produces a clean INDETERMINATE/RECOVERY_FAILED finding, never a thrown exception. Zero network calls: does not confirm the authorization was ever submitted on-chain, does not confirm the EOA's account nonce matches the declared nonce at any block, and makes no settlement claim.

**Tool URL:** https://ainumbers.co/chaingraph/art-614-eip7702-authorization-tuple-decoder.html

## Request body

- object
  - `chainId` number
  - `address` string
  - `nonce` number
  - `signature` string
  - `r` string
  - `s` string
  - `v` number
  - `yParity` number

## Response `200`

Successful tool execution result

- object
  - `verdict` string
  - `reasons` string[]
  - `chain_id` number, nullable
  - `cross_chain_authorization` boolean, nullable
  - `delegate_address` string, nullable
  - `nonce` number, nullable
  - `authorization_tuple_hash` string, nullable
  - `recovered_signer` string, nullable
  - `recovery_id` number, nullable
  - `recovery_id_source` string, nullable
  - `scope_note` string

---

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