Your AI agent just swapped $2M into an unaudited liquidity pool. The transaction confirmed in 12 seconds. There is no undo button.

rules:
  # Cap swap amounts
  - name: large_swap_approval
    description: Swaps over $50K require trading desk approval
    tool: swap_tokens
    when: args.amount_usd > 50000
    action: require_approval
    message: "Swap of ${{args.amount_usd}} exceeds $50K auto-approval limit"
    approvers: ["trading-desk@example.com"]

  # Enforce slippage tolerance
  - name: slippage_cap
    description: Block swaps with excessive slippage tolerance
    tool: swap_tokens
    when: args.max_slippage > 0.03
    action: deny
    message: "Slippage tolerance {{args.max_slippage}} exceeds 3% maximum"

  # Token allowlist
  - name: approved_tokens_only
    description: Only trade approved tokens
    tool: swap_tokens
    when: args.token_in NOT IN ["USDC", "USDT", "ETH", "WETH", "WBTC", "DAI"]
    action: deny
    message: "Token {{args.token_in}} is not on the approved trading list"

rules:
  # Approved bridge protocols only
  - name: bridge_allowlist
    description: Only use audited bridge protocols
    tool: bridge_assets
    when: args.bridge_protocol NOT IN ["stargate", "layerzero", "wormhole", "across"]
    action: deny
    message: "Bridge protocol '{{args.bridge_protocol}}' is not approved"

  # Bridge value cap
  - name: bridge_value_limit
    description: Large bridge transfers require approval
    tool: bridge_assets
    when: args.amount_usd > 100000
    action: require_approval
    message: "Bridge transfer of ${{args.amount_usd}} exceeds $100K limit"

  # Block unlimited token approvals
  - name: no_unlimited_approvals
    description: Prevent agents from setting unlimited token allowances
    tool: approve_token_spending
    when: args.amount == "unlimited"
    action: deny
    message: "Unlimited token approvals are prohibited by policy"

import { Veto } from "veto-sdk";

const veto = new Veto({ apiKey: process.env.VETO_API_KEY });

// Your existing DeFi tools — unchanged
const defiTools = {
  swap_tokens: async (args: {
    token_in: string;
    token_out: string;
    amount_usd: number;
    max_slippage: number;
    dex: string;
  }) => {
    return await dexRouter.executeSwap(args);
  },

  bridge_assets: async (args: {
    token: string;
    amount_usd: number;
    source_chain: string;
    dest_chain: string;
    bridge_protocol: string;
  }) => {
    return await bridgeSDK.transfer(args);
  },

  provide_liquidity: async (args: {
    pool_address: string;
    amount_usd: number;
    token_a: string;
    token_b: string;
  }) => {
    return await liquidityManager.addPosition(args);
  },
};

// Wrap with Veto — one line per tool
const protectedTools = veto.wrapTools(defiTools, {
  policy: "defi",
  context: { agent_id: "yield-optimizer-v3" },
});

// Use protectedTools in your agent framework
// ElizaOS, Virtuals GAME, Olas, LangChain — all supported