What is Permit2?
Permit2 is a token approval protocol by Uniswap that provides a unified, more secure allowance system for ERC-20 tokens — featuring built-in expiration, signature-based approvals (no on-chain transaction needed), and batch operations.
WHY IT MATTERS
Standard ERC-20 approvals have problems: they never expire, they require an on-chain transaction to set, and each protocol needs its own approval. Permit2 solves all three.
With Permit2, you approve the Permit2 contract once per token. Then, you grant sub-approvals to individual protocols using off-chain signatures — no gas cost. These sub-approvals have built-in expiration (they automatically become invalid after a set time) and amount limits.
For agent wallets, Permit2 is a significant security improvement. Instead of agents granting unlimited, permanent approvals to every DeFi protocol, they use time-limited, amount-scoped Permit2 signatures. If a protocol is compromised, the damage window is limited by the permit's expiration.
HOW POLICYLAYER USES THIS
PolicyLayer can leverage Permit2 for granular agent token permissions — setting specific amounts, expiration times, and approved spenders for each permit. This provides tighter control than standard ERC-20 approvals.