AgentShield: Pre-Execution Security Firewall for Autonomous AI Agents

AgentShield is a pre-execution security firewall for autonomous AI agents built for the OKX AI Genesis Hackathon.

🔐 THE PROBLEM

AI agents are increasingly executing on-chain transactions autonomously. Without a security layer, they can approve unlimited token spending, fall for phishing scams, or drain wallets. AgentShield sits between the agent and the blockchain, analyzing every action before it executes.

⚙️ HOW IT WORKS

1. User defines a security policy in plain language (e.g. "Block scams, max 50 STT per tx")

2. AI agent proposes an on-chain action

3. AgentShield runs deterministic checks (instant, free) — catches obvious attacks

4. If not blocked, Gemini 2.5 Flash performs deep LLM analysis

5. Returns verdict: ALLOW, WARN, or BLOCK with risk score (0-100)

🏗️ ARCHITECTURE

- Smart contracts on Somnia Testnet (7 contracts, 171 tests, 0 failures)

- MCP endpoint powered by Gemini 2.5 Flash for real-time AI analysis

- Registered as ASP #5936 on OKX.AI marketplace

- Frontend demo: agentshield-dusky.vercel.app

🛡️ SECURITY

- Deterministic-first: hard blocks cost zero gas, no LLM needed

- Fail-safe: unexpected AI output defaults to WARN, never ALLOW

- On-chain verifiability: all scans stored permanently

- 171 tests, production-ready, not a prototype

🏆 WHY AGENTSHIELD WINS

- Complete product: contracts + endpoint + demo, all functional

- Real security value: protects agents from the #1 attack vectors

- Dual-chain: Somnia for LLM inference, OKX.AI for distribution

- Best Product + Software Utility + Finance Copilot categories