Agentpay

AgentPay

**Security plugin for Claude Code that protects agent-to-agent payments and transactions.**

Built at the [Kaszek & Anthropic Buenos Aires Hackathon 2026](https://dev.kaszek.com/) -- Open Track.

Install and use

As a Claude Code plugin:

claude plugins marketplace add garagon/agentpay
claude plugins install agentpay@agentpay

Or via npm:

npm i -g agentpay-security && agentpay install

Or from source:

git clone https://github.com/garagon/agentpay && cd agentpay
go build -o agentpay-bin . && ./agentpay-bin install

Once installed, AgentPay runs automatically on every tool call. Try the demo:

agentpay demo        # Run 7 attack scenarios
agentpay scan .      # Scan for compromised npm packages
agentpay audit       # View payment audit trail

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What we built

AgentPay is a Claude Code plugin that intercepts financial tool calls in real time, detects when a compromised MCP server tampers with payments, and blocks fraud before money moves. It also detects and quarantines compromised npm packages (axios supply chain attack).

• Real-time payment guard -- 5-stage security pipeline on every financial tool call
• Payment drift detection -- Catches when a MCP changes the recipient, amount, or currency
• Supply chain scanner -- Detects and removes compromised axios versions from node_modules
• Tamper-evident audit -- Every decision logged with SHA-256 hash chain

No existing Claude Code plugin or MCP middleware provides financial security for agent transactions.

Why this matters

We are in the middle of a fundamental shift in how software is built and operated. The risks are compounding:

1. 90% of code is AI-generated -- Agents write, review, and ship code with minimal human oversight. The attack surface is no longer just human error.
2. MCP/library supply chain is vulnerable -- Compromised packages like axios (v1.7.8, 1.7.9) ship malicious postinstall scripts that exfiltrate c