Quick answerWhen your AI agent's output feeds straight into another vendor's automated system with no human checking it in between, default liability rules (who acted, who could have caught the error) break down, because neither party had a human moment to catch the mistake. Allocate liability by contract before this happens, not after: name which party's system is authoritative for validating the output before it's acted on, cap each party's liability by reference to who controlled the last opportunity to add a check, and require both sides to log what was sent and received so a dispute doesn't come down to conflicting reconstructions. Waiting to negotiate this after a chained failure means negotiating from a position where you've already caused the downstream party financial harm.
Why this is different from your own direct liability
Your company's liability when your AI agent gives your own customer wrong information is a two-party problem: you and the customer you harmed. Chained automation is a three-or-more-party problem: your agent produces an output, a second vendor's automated system consumes it and takes an action, and the harm lands on a customer or business relationship neither of you directly controls end-to-end. The real-time multi-agent orchestration protocol covers how two agents coordinate technically mid-conversation; it doesn't answer who pays when the coordination goes fine technically but the downstream action was still wrong.
The three questions to settle in the contract
First: which party's system is supposed to be the last validation point before an action executes. If your agent's output format was correct and complete, but the downstream vendor's system misapplied it, that's a different failure than your agent sending malformed or incorrect output in the first place — the contract should assign responsibility based on which side owned the check that should have caught it. Second: what happens when the failure can't be cleanly attributed to one side, because both sides' automation behaved exactly as designed and the harm still occurred — this is the most common real-world case, and it needs a default (usually proportional, sometimes capped per-incident) rather than being left to be litigated fresh each time. Third: what logging both sides commit to keeping, since a liability dispute about an automated exchange with no human witness lives or dies on whether you can reconstruct exactly what was sent and when.
Compare this to the safeguards you'd want on the inbound side
Nailing down rate limits, a liability clause, and a circuit breaker before a customer's AI agent talks to yours covers the inbound direction: someone else's automation calling into your systems, where you're the one exposed to a misbehaving caller. This is the outbound mirror of that problem — your agent's output is the thing landing in someone else's automated pipeline, and you're the one who needs the liability terms and the validation checkpoint clearly assigned before the first live exchange, not the vendor whose system consumes what you send.
Build the technical checkpoint the contract assumes exists
A liability clause is only enforceable if there's a real checkpoint to point to. At minimum, have your agent emit output in a structured, versioned format the downstream system can validate against a schema before acting on it — not free-text that the receiving system has to interpret. Log the exact payload sent, the receiving system's acknowledgment, and any transformation that happened on either side. When a dispute happens, whoever can produce a complete, timestamped record of what actually crossed the boundary is in a materially stronger position than whoever can only describe what should have happened.
FAQ
Does a liability cap protect us if our agent's output was clearly wrong? A cap limits the size of exposure, not whether you're liable at all. If the contract makes clear your agent's output was supposed to be validated by the downstream vendor's system before acting, you're still exposed for producing wrong output in the first place — the cap just bounds the damages, it doesn't eliminate the underlying liability.
What if we don't have a direct contract with the downstream vendor at all? This is the riskiest version of the scenario — your customer's own automation, or a fourth-party system you've never negotiated with, consumes your agent's output. Without a contract, you're relying on general liability law and whatever your terms of service say about automated downstream use, which is a much weaker position. Require customers to disclose downstream automated consumption of your agent's output as a condition of use if you can't get a direct contract with every party.
Should we validate our own output before sending it, even if the contract says the other side validates? Yes. A contractual allocation of responsibility for validation doesn't mean you should skip your own sanity checks — it determines who pays when something slips through, not whether you should try to prevent it slipping through in the first place.