PayScope — Scoped Payment Authorization for AI Agents

The Problem

No spending limits

AI agents with wallet access can drain your entire balance — there's nothing stopping them.

No purpose enforcement

An agent authorized to pay for "cloud services" can just as easily pay for anything else.

No audit trail

You can't verify what was spent, when, or why — until it's too late.

The Solution

💰 Scoped budgets

Fund a scope with exactly the ETH you want an agent to spend. Contract enforces the limit.

🎯 Purpose binding

Agents can only spend for the declared purpose. "cloud services only" means exactly that.

📋 On-chain audit

Every payment is logged on-chain with a memo. Immutable, verifiable, permanent.

🔒 Owner control

Revoke any scope instantly. Unspent ETH returned immediately. No lockup.

Live Demo — Sepolia Testnet

node demo.js

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║ PayScope AI Agent — Live Demo on Sepolia ║

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Contract : 0x856737FA015CBFB3a9e87cE047CB5D5f46905DFB ↗

Network : Sepolia Testnet

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║ Step 1 — Owner creates a payment scope for AI agent ║

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Purpose : cloud services only

Budget : 0.005 ETH

Tx sent : 0x59382cb9...5ca1f ↗

Confirmed in block 10497530 ✓

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║ Step 3 — Agent executes legitimate payment ║

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Request : Pay 0.001 ETH for "cloud storage service"

Agent evaluating... purpose matches scope "cloud services only" ✓

Agent evaluating... amount 0.001 ETH within budget 0.005 ETH ✓

Agent decision: APPROVED

Tx sent : 0x4ff81c98...4e14a2 ↗

Payment confirmed in block 10497531 ✓

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║ Step 4 — Agent rejects out-of-scope request ║

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Request : Pay 0.001 ETH for "buy NFTs"

Agent evaluating... purpose "buy NFTs" does NOT match scope "cloud services only" ✗

Agent decision: REJECTED — purpose mismatch, payment blocked.

(No transaction sent, no gas spent)

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║ Step 5 — On-chain audit trail ║

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Total payments executed: 1

Tx : 0x4ff81c98...4e14a2 ↗

Amt : 0.001 ETH

Memo : cloud storage service

Remaining budget: 0.004 ETH

On-chain Transactions

DEPLOY Contract deployed → 0x856737FA015CBFB3a9e87cE047CB5D5f46905DFB ↗
SCOPE Payment scope created (0.005 ETH budget, "cloud services only") → 0x59382cb9... ↗
APPROVED Agent pays 0.001 ETH for "cloud storage service" → 0x4ff81c98... ↗
REJECTED Agent blocks "buy NFTs" — purpose mismatch, no tx sent