Biconomy has proposed a new Ethereum standard, ERC-8211, that introduces “smart batching” so AI agents and smart accounts can execute complex, multi-step DeFi operations in a single transaction while resolving each step’s parameters at execution time rather than at signing. The standard, published on April 6, 2026, is designed as a contract-layer encoding that works with existing account-abstraction frameworks and does not require any Ethereum protocol fork.

According to Biconomy, ERC-8211 addresses a core bottleneck in today’s DeFi infrastructure: most batch systems lock all parameters before a transaction hits the chain, even when later steps depend on outputs that are unknown in advance, such as the exact proceeds of a token swap or a lending withdrawal. “Smart batching resolves parameters at execution time,” the ERC-8211 specification explains, allowing each parameter in a batch to declare how its value should be obtained — as a literal, via a static call, or from an on-chain balance — and what constraints it must satisfy before the batch can continue.

How ERC-8211 works

The ERC-8211 spec describes a batch format where every input parameter carries three pieces of information: a fetcher type to define how the value is sourced, routing information that decides whether it becomes a call target, value field or calldata, and inline predicates that must hold or the entire batch reverts. That structure lets an AI agent express flows like “swap token A for token B on Uniswap, then deposit whatever actually arrives into Aave,” with the second step pulling its amount from the resolved output of the first call rather than a guessed number.ethereum-magicians+3

Smart batching also introduces assertion-only “predicate entries,” where a batch step has no call target and instead encodes a boolean condition on chain state — for example, asserting that a wallet’s WETH balance remains above a safety threshold after a leverage loop. These predicates use the same runtime resolution path as regular actions and act as gates between steps, turning a batch into what the spec calls “a program with embedded safety checks, not a hopeful script.”

Tying into Ethereum’s UX and agent roadmap

In comments to Decrypt, Ethereum Foundation research scientist Barnabé Monnot said ERC-8211 fits directly into the organization’s user-experience roadmap. “The protocol cluster of the Ethereum Foundation has ‘Improve UX’ as one of its strategic priorities,” Monnot said, adding that “ERC-8211 support is coming from this strategic priority” and that the collaboration with Biconomy began during a 2025 workshop convened by the Foundation’s Improve UX initiative.

Monnot argued that “the agentic execution angle is new, but has imposed itself given the rapid developments of agents over the last three months,” calling ERC-8211 “a perfect use case since agents can orchestrate complex cross-chain interactions, and ERC-8211 gives them the right platform to do so.” Biconomy, which describes itself as “the smart wallet and execution engine for high-performance DeFi and autonomous onchain agents,” has previously worked on account-abstraction tooling and gasless UX, and says ERC-8211 can be implemented directly in TypeScript clients that construct batches against its encoding.