manex-tech/tapproved

AI agents cannot spend above their routine limit without a physical approval.
Project tracking: Master Development Checklist — canonical task-by-task progress, verification evidence and next checkpoint.
Tapproved is a testnet prototype for hardware-backed spending authorization on NEAR. A registered agent requests payments from a contract-controlled treasury. The contract enforces spending policy. Payments within the soft limit can be executed automatically; larger payments require an Ed25519 signature from a registered ESP32 device after a physical button press.
Network: NEAR testnet
Contract: manextech.testnet
Agent: manex-agent.testnet
Hardware: ESP32-WROOM-32, approval button on GPIO25
This repository is under active development for the NEAR Hackathon. It is not audited and must not be used with production keys or real funds.
## How it works
1. The registered agent calls requestspend on the contract.
2. The contract checks that spending is not paused, no other payment is active, the recipient is allowlisted, the amount is positive and within the hard per-payment limit, and the UTC-day reservation remains within the daily limit.
3. Amounts at or below the soft limit become approved. Larger amounts become pending.
4. An automatically approved payment can be executed with executeapprovedspend. A pending payment requires the ESP32 to sign the canonical approval message after a physical GPIO25 press; the signature is submitted to approvespend.
5. The contract transfers NEAR from its own account and a private callback records paid or failed. Expired pending/approved payments are also cleaned up when the next valid request arrives; owner cancellation releases eligible reservations.
The contract is the policy authority. The relay authenticates agent requests, persists idempotency state, submits requestspend through a restricted FunctionCall key and executes only contract-approved low-value payments. Pending hardware approvals travel over the bounded USB serial bridge to the ESP32; the relay verifies the returned device key and Ed25519 signature before submitting approvespend through a separate approval-only key. Authenticated APIs expose payment state and transaction receipts. A separate expiry-only FunctionCall key lets a background monitor call the contract's permissionless expirepayment method after the finalized NEAR block time passes the payment expiry.
## Current project status
| Component | Current status |
| NEAR contract policy and spend lifecycle | Implemented; Rust tests and Wasm build in CI |
| Hardware Ed25519 verification and transfer callback | Implemented |
| Testnet deployment | User-confirmed deployed and tested using NEAR CLI; see deployment status |
| ESP32 approval firmware | Implemented prototype; exact NEAR and yoctoNEAR approval summary, recipient/payment ID presentation, fresh debounced GPIO25 press/release approval, 32-request duplicate-ID rejection, fail-closed NVS seed-record handling, PlatformIO build and host-compiled amount/button/replay-state and zeroizing-buffer tests plus byte-for-byte shared approval-vector verification for the firmware encoder in CI; D1 source audit completed with nine findings allocated to Phase D follow-through |