Session Policies Overview

Agent gets a session quote with instructions and submits it for execution
        ↓
MEE broadcasts the transaction to blockchain
        ↓
Smart contract checks:
  ✓ Is this contract/function allowed?
  ✓ Do parameters pass all policy rules?
  ✓ Is the session still valid (time)?
  ✓ Is usage limit not exceeded?
        ↓
All checks pass → Execute
Any check fails → Revert

const functionSignature = toFunctionSelector(
  getAbiItem({ abi: UniswapRouterAbi, name: "exactInputSingle" })
);

const customActions = mcNexus.buildSessionAction({
  type: "custom",
  data: {
    chainIds: [8453, 10],
    contractAddress: UNISWAP_ROUTER,
    functionSignature,
    policies: [
      // Time limit
      {
        type: "timeframe",
        validAfter: now,
        validUntil: now + 7 * DAY,
      },
      // Usage limit
      {
        type: "usageLimit",
        limit: 5n
      },
      // Spending limits
      {
        type: "universal",
        rules: [
          {
            condition: "equal",
            calldataOffset: calldataArgument(2),
            // 10 USDC per tx
            comparisonValue: parseUnits("10", 6)
          }
        ],
      }
    ]
  }
});

Is the target contract fully trusted?
├─ Yes: Consider Timeframe + No other restrictive policy
└─ No: Use Universal Action

Does the agent handle user funds?
├─ Yes: Universal Action with spending limits
└─ No: Sudo may be acceptable

Need to limit total actions?
├─ Yes: Add Usage Limit
└─ No: Timeframe may suffice