A DeFi agent may read documentation, interpret a request, prepare a transaction, and ask a wallet to execute it. Those steps have different consequences. Designing the system starts with deciding which actions it can actually authorize, then placing enforceable limits around those actions. A persuasive explanation from the agent should never be the mechanism that grants it more power.
The DeFi agent topic introduces the components of an automated workflow. This guide focuses on permission design: what an agent may propose, what a signer may approve, and what the wallet or contract must reject. The aim is an operating plan that remains understandable even when the model misunderstands its input.
Write the permitted task in concrete terms
Start with a sentence describing the narrow job. “Prepare a weekly report about these positions” is a different task from “move assets among these contracts.” A report may only need read access. Transaction preparation may need network data and simulation. Execution introduces signing authority and should be designed as a separate capability.
Replace open-ended verbs such as manage, optimize, or maximize with explicit actions. Identify the network, assets, contracts, permitted methods, recipients, amounts, and time window. State which changes require fresh human review. This creates a specification you can compare with the permissions the implementation actually supports.
Also define a successful refusal. If the requested destination is missing, the price data is stale, or the transaction cannot be decoded, the appropriate system behavior may be to stop and explain the missing input. Design that outcome deliberately. Otherwise, pressure to finish the task can become an invitation to guess.
Separate planning from the authority to sign
Keep the component that interprets language separate from the component that decides whether a transaction is permitted. Have the planner produce a structured proposal containing the chain, target, method, arguments, value, and reason. A policy checker should evaluate those fields before any signing step. Natural-language confidence is irrelevant to that check.
For a manually reviewed workflow, the signer should present the decoded action and its material effects. For an automated workflow, require the same fields to satisfy explicit constraints. Keep secrets out of prompts, retrieved documents, and ordinary logs. The planner should request an authorized operation rather than receive a general-purpose wallet recovery secret.
The AI and DeFi topic helps distinguish research assistance from transaction automation. Make that distinction visible in the product as well: show whether the agent is reading, proposing, awaiting review, or executing. A clear state reduces accidental authorization caused by ambiguous interface language.
Check what session permissions really enforce
The ERC-4337 documentation on session keys and delegation explains that smart accounts can authorize constrained sessions, but enforcement depends on wallet-specific logic. ERC-4337 does not automatically supply a universal session-permission system. A wallet's support for account abstraction therefore does not, by itself, establish the limits of an agent's authority.
Inspect the exact implementation and version. Can it restrict target contracts, methods, recipients, token amounts, native value, and expiry? Where are those restrictions checked? Can the delegate change permissions or create a broader delegation? Ask for an explanation of the enforcement path rather than accepting a settings screen as evidence.
Test the boundary with a deliberately disallowed proposal in a controlled environment. Change the recipient, exceed the budget, or use an unapproved method and confirm that execution is rejected. A message from the model saying it will follow the rules is a different observation from a wallet refusing an invalid operation.
Inspect the actions behind an approved method
Consider a hypothetical router that accepts a destination and a list of calls. Allowing its contract address alone would leave important behavior unspecified. The permission review must consider the supplied destinations, permitted methods, and token movements inside the request. Decide whether the implementation can enforce those details before authorizing that route.
Apply the same review to batches. Define whether every item must satisfy the policy independently and whether the combined value fits the remaining budget. Include a test in which a permitted-looking batch contains one disallowed action. The expected result should be rejection of the unauthorized execution, with enough information to explain the policy decision. This turns a broad statement about restricted access into an observable behavior.
Treat token approvals as a separate permission surface
ERC-20 allowances authorize a spender to transfer a specified amount of a holder's tokens through the token's allowance mechanism. Review these permissions separately from the agent's session. Stopping an agent process does not itself clear permissions previously granted to another contract.
For every proposed approval, identify the token, spender, amount, network, and purpose. Explain whether the approval is required for the immediate action or establishes continuing access. If a route uses an intermediary approval system, include that system in the review. The Ethereum approvals guide provides a companion checklist.
Give the shutdown procedure an allowance review. Determine which permissions should remain and which must be removed, then verify the resulting state. Revocation cannot undo a completed transfer, so it belongs alongside narrow initial authorization and monitoring. It should not be the only control protecting the position.
Budget for cumulative behavior
A per-transaction limit is only one constraint. A hypothetical agent allowed to repeat the same action indefinitely could create a much larger cumulative exposure. Define the total budget, its accounting period, allowed frequency, and whether concurrent tasks share the same limit. Ensure the enforcement method matches that design.
Include fees, native-token value, and permitted recipients in the budget. Decide what happens after a failed transaction or an uncertain submission result. Before retrying, the system should determine whether the intended action already occurred. Otherwise, an operational error can turn a single instruction into repeated execution.
Put permission changes outside the agent's ordinary workflow. An exhausted budget should produce a request for review with the relevant evidence. It should not trigger a search for a different route that avoids the limit. This is a design requirement you can test with hypothetical edge cases before enabling execution.
Use simulations and independent transaction checks
Before signing, compare the decoded transaction with the original permitted task. Check the chain, destination, function, transferred value, approvals, and expected assets received. Use a simulation where appropriate, then review what assumptions the simulation depends on. Treat it as evidence about a proposed execution rather than a promise about every future chain state.
Define explicit handling for stale quotes, changed contract versions, failed simulations, and unavailable network services. A bounded system should stop when an essential check cannot be completed. Record the check that failed so a human can resolve the problem without reconstructing the entire conversation.
Keep retrieved websites and token metadata on the information side of the boundary. Text encountered during research may be inaccurate or adversarial. It should never become a new policy instruction merely because the planner read it. Trusted configuration should identify which data fields may inform a proposal and which rules remain fixed.
Rehearse shutdown and recovery
Use a hypothetical incident exercise: the agent begins proposing transactions outside its task after reading an unexpected document. Who notices? Which component rejects the proposals? How do you suspend the job, revoke the session, and check pending transactions? Assign a responsible person or process to each step.
Separate disabling the scheduler from revoking onchain authority. Depending on the implementation, both actions may be needed. Preserve a minimal incident record containing proposals, policy decisions, signatures, transaction identifiers, and observed outcomes. Exclude private keys and unnecessary personal data from that record.
Restart only after identifying which assumption failed. A different prompt may improve the planner's output, but the permission boundary should still enforce the same limits. Rehearse the stop procedure during setup so it remains usable when attention and time are limited.
Conclusion: make the limits observable
A useful DeFi agent has a task you can state, permissions you can inspect, and refusal behavior you can test. Keep planning separate from signing, examine session and token permissions independently, and define cumulative limits and recovery steps. For the research stage feeding those proposals, continue with the LLM verification workflow. Automation becomes easier to assess when every consequential action has an explicit boundary.
