Programmable Session Rules vs. Fixed Session Rules

Dynamic session logic defined by the dApp developer. This enables:

• Granular permissions: Limit session to specific contract functions (e.g., swap() but not approve()).
• Conditional logic: Set spending caps per session, time-based expiry, or whitelisted assets.
• Use Case: Essential for complex DeFi interactions, gaming sessions, or subscription models where trust needs fine-tuning.

Increased implementation complexity. Developers must:

• Design and audit custom rule sets, increasing attack surface.
• Manage rule updates and migrations.
• Use Case: A poor fit for simple, one-off transactions or teams with limited security audit resources. Adds friction for MVP launches.

Pre-defined, audited session templates (e.g., ERC-7579). This provides:

• Lower risk: Rules are standardized and battle-tested across the ecosystem.
• Faster integration: Plug-and-play for common patterns like token approvals with a cap.
• Use Case: Ideal for wallets (like Rabby, Frame) offering user-safe defaults, or dApps needing quick, reliable session enablement.

Limited to pre-built scenarios. Cannot accommodate:

• Novel transaction types or custom protocol logic.
• Complex multi-step workflows within a single session.
• Use Case: A constraint for innovative DeFi primitives, on-chain games with unique mechanics, or any application requiring bespoke trust boundaries.

Dynamic, Granular Control: Developers can define complex, stateful logic for session keys (e.g., max spend per token, specific contract allowlists, time-based expirations). This enables use cases like subscription payments (recurring fees) or gaming sessions (limited in-game actions).

Increased Attack Surface & Audit Burden: Custom smart contract logic introduces new vulnerabilities. Each session rule module requires rigorous auditing (e.g., by firms like OpenZeppelin or Trail of Bits). A bug can lead to drained session keys, as seen in early ERC-4337 wallet implementations.

Predictable Security & Simplicity: Rules are hardcoded and standardized (e.g., validUntil timestamp, spendingLimit per transaction). This reduces audit scope to the core protocol (like Safe{Wallet} modules) and minimizes unexpected behavior, providing a safer default for high-value DeFi operations.

Inflexible for Advanced dApps: Cannot adapt to complex user journeys. For example, a DeFi aggregator requiring multi-hop swaps within a session, or an NFT marketplace needing batch listings, would be forced into multiple wallet confirmations, degrading UX and increasing gas fees.

Dynamic, on-chain logic: Enables sessions to adapt based on real-time conditions (e.g., gas prices, user reputation, DApp state). This matters for DeFi applications like Aave or Uniswap, where a session might need to adjust spending limits based on pool liquidity or collateral ratios.

Increased complexity & attack surface: Requires rigorous smart contract auditing. A bug in the session logic (e.g., in a custom rule for a gaming DApp like Axie Infinity) can lead to drained user wallets. This adds development overhead and risk compared to simple, battle-tested fixed rules.

Predictable security & gas efficiency: Rules are hardcoded (e.g., max spend limit of 1 ETH, specific contract allowlist). This matters for high-frequency trading bots or NFT minting sessions, where gas cost predictability and minimal on-chain verification are critical for profitability and speed.

Inflexible user experience: Cannot adapt to contextual changes without ending the session. For a social DApp like Farcaster or a multi-step bridge transaction, this forces users to re-approve sessions frequently, harming UX and increasing friction for complex operations.