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To prove an AI agent’s on-chain action was authorized, connect the owner’s grant to the agent and wallet, bind that grant to the exact action, show that an on-chain execution path enforced the authorization, and link the check to a successful transaction. A signature, registry entry, policy verdict, or transaction receipt alone proves only part of that chain.
What evidence shows an AI agent was allowed to make this transaction?
A verifier should be able to follow a traceable evidence chain from the person or entity granting authority to the precise call that succeeded. The records should identify the relevant policy version and state at the transaction’s block or time, not just show what a policy says today.
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- Delegation and identity: identify the owner or delegator, the agent, and the wallet address allowed to act for it. Preserve how that wallet was bound to the agent.
- Grant and scope: preserve the active policy or a verifiable commitment to it, including permitted actions and targets, limits, activation and expiry, and its identifier. Include applicable revocations or policy updates.
- Action-specific authorization: preserve the signature, attestation, or proof and the fields it covers: the agent, target, function and arguments or action digest, value, nonce or equivalent replay control, validity window, and governing policy identifier or root.
- Enforcement evidence: show that the account validation path, wallet policy module, or target contract actually checked the authorization before it permitted execution.
- Execution evidence: provide the chain and transaction hash, block, receipt, relevant events, decoded call, and an outcome check demonstrating that the authorized action succeeded.
- Integrity and record completeness: retain the policy history, signatures, nonces or nullifiers, attestations, receipts, and audit entries in a tamper-evident form. If records are hash-chained, provide evidence that the sequence is complete enough for the verifier’s purpose.
These pieces answer different questions. A signature shows that a key approved the fields it signed; enforcement evidence shows that the authorization gate was applied; execution evidence shows what happened on-chain. The verifier needs them linked together.
How to assemble and verify the proof chain
1. Establish the owner, agent, and wallet relationship
Record the asset owner or delegator, the agent’s identity, and the exact wallet address authorized to act. ERC-8004 describes an identity registry with an agentWallet field. In that design, changing the wallet requires an EIP-712 signature for an externally owned account (EOA) or ERC-1271 verification for a smart-contract wallet. This can establish a wallet-control link in the registry; it does not grant permission for a specific transfer, swap, or contract call.
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2. Resolve the grant that applied at execution time
Keep the policy version that governed the transaction and enough history to determine whether it was active or revoked at the relevant block or time. ERC-8196 describes policy fields including owner and agent addresses, allowed action names, permitted and blocked contracts, per-transaction and optional daily value limits, activation and expiry times, and a policy identifier. A policy hash can be included in action data so the verifier can identify which grant the authorization refers to.
3. Check that the authorization names this exact action
Compare the signed or proven fields with the decoded transaction. They should bind the target, function and arguments or equivalent calldata digest, value, nonce or other uniqueness marker, validity window, agent, and policy hash or root. Include chain or account context where needed to prevent the same authorization from being replayed in a different context.
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ERC-8196 specifies EIP-712 action and delegation structures that include the agent, action, target, value, calldata, nonce, expiry, and policy hash; its action structure also includes an entropy commitment. ERC-8273 explains that a nonzero action digest should bind the target contract, function selector, arguments, and nonce or equivalent uniqueness value. If changing the recipient, token, amount, or calldata would leave the authorization valid, it does not establish that the changed action was approved.
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Locate the check in the account’s validation path, an account policy module, or the target contract’s gate. An off-chain service may evaluate policy, but its log is weak evidence if the agent can submit a transaction that bypasses that service.
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ERC-8196 describes an authenticated-wallet interface and policy enforcement. ERC-8273 describes an atomic attestAndCall flow in which a target can query an active attestation for a wallet, capability, and action digest. For the ERC-4337 UserOperation profile it describes, ERC-8273 says implementations must verify that the operation sender is the attested wallet, that the account authorizes the operation through its nonce, signature, session key, or module policy, and that the executed action matches the digest.
5. Confirm success, not just submission
A transaction hash proves that a transaction was submitted, not necessarily that the intended call succeeded. Inspect the receipt and relevant events, decode the call, and verify the result against an appropriate postcondition. Where possible, independently replay the relevant receipt and state checks.
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ERC-8273 cautions that a low-level call to EntryPoint.handleOps returning without a revert does not by itself establish target-action success in implementations where a failed UserOperation is represented by an event. An adapter should confirm an account or DApp receipt, event proof, or another verifiable postcondition.
6. Preserve an auditable record
Retain the signed authorization, applicable policy and revocation history, nonce or nullifier state, attestations, transaction receipt, and decision and execution records. ERC-8196 describes a hash-chained audit trail and permits off-chain entries with periodic Merkle roots anchored on-chain. A hash chain can expose edits within a supplied sequence, but it cannot by itself show that no entries were omitted. Anchored roots, independently held checkpoints, or other completeness evidence can help address that concern.
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How the main authorization approaches differ
The standards describe different ways to represent and verify authorization. They are design specifications, not proof that a particular deployment implements the design correctly.
| Approach | What a verifier can inspect | Useful comparison questions | Important limitation |
|---|---|---|---|
| Explicit wallet or module policy (ERC-8196) | Owner-defined actions and contracts, spending limits, time bounds, signatures, and policy hash | Is the policy inspectable? How are policy updates and revocation handled? What state and gas costs does enforcement require? | The interface or design does not establish that a deployed implementation conforms to it. |
| Transaction-scoped attestation (ERC-8273) | An attestor’s on-chain statement, optionally linked to an evidence hash and bound to a capability and action digest | Is the action bound precisely? Who is trusted as attestor? Is checking atomic with execution, and does the flow support the wallet’s execution path? | The attestation reflects the attestor’s assumptions and is not necessarily itself a cryptographic proof. |
| Confidential policy verdict (ERC-8354) | A verifiable zero-knowledge verdict tied to an agent, policy root, action commitment, executor, expiry, and single-use nullifier | What assumptions does the proof system and verifier make? Is the policy root current? Is the action bound and replay-protected? | It proves that the committed interpreter returned ALLOW, not that the policy is safe or sensible. Actions on a public chain remain public. |
ERC-4337 smart accounts add programmable validation and execution paths. Its standard also identifies the EntryPoint as a concentrated trust point, so a verifier should consider how that component is validated and what the deployed account actually checks.
What each piece of evidence does—and does not—prove
- Valid signature: supports that the corresponding key signed the fields covered by the signature, subject to key security, domain separation, and implementation correctness. It does not show that an omitted policy was applied.
- Policy verdict: supports that a particular evaluation passed under the proof’s commitments and verifier assumptions. ERC-8354 explicitly limits its verdict to the integrity of the committed evaluation; it does not establish that the underlying policy is correct, fair, or non-malicious.
- Identity registration: supports a registered agent and wallet-control relationship. It is not a transaction-specific grant.
- Transaction receipt: supports an on-chain outcome. It must still be connected to the authorization and decoded action to establish that the outcome was authorized.
- Audit hash chain: helps detect modification of linked entries. It does not establish that the supplied sequence contains every relevant entry.
- Standards document: describes a design, not the behavior or safety of a deployed contract. Check the deployed code, configuration, policy state, and execution at the relevant block.
What to inspect in a real transaction
For a practical review, compare the evidence rather than relying on a vendor summary or screenshot:
- Does the wallet address in the transaction match the wallet bound to the agent and the wallet named in the authorization?
- Was the cited grant active, unrevoked, and within its limits at the transaction’s block or time?
- Do the target, function, arguments, recipient, token, amount, and value in the executed call match the signed fields or committed action digest?
- Was the nonce, expiry, nullifier, or other replay control valid and unused when authorization was checked?
- Can you identify the account or contract code path that enforced the check, rather than only an off-chain approval record?
- Does the receipt and outcome evidence show success for that same action?
- Can the audit record be checked for both integrity and, where required, completeness?
Authorization is a relationship between a principal’s grant, an agent and wallet, a concrete action, and valid policy state at a particular time. Calling software an “AI agent” does not establish that relationship.
Standards referenced
The standards discussed here are Ethereum Improvement Proposals: ERC-8004 for agent identity, ERC-8196 for authenticated wallets and policy enforcement, ERC-8273 for transaction-scoped attestations, ERC-8354 for confidential policy verdicts, and ERC-4337 for account abstraction. Proposal status and specifications can change; the descriptions here reflect the versions accessed on October 5, 2026. No claim about any particular wallet, agent, contract deployment, or transaction follows from a standards specification alone.
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