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Agent design • Field note

Make your agent check its own answer before anyone sees it

Chip designers stopped trusting an agent's first draft and wired in the tools that grade it. A support reply that quotes a refund or a delivery date deserves the same check.

David Soden • 5 min read • 30 September 2026
A technician looks through a stereo microscope while holding a circuit board under a ring light
In chip design, nothing ships until a separate tool has checked it. The agent is held to that rule too.

What happened

Siemens expanded its partnership with NVIDIA to build what it calls self-verifying agents into its chip and circuit board design software. The agents plan and carry out long engineering tasks, and at each step Siemens' own simulation and verification tools check the result before the agent moves on.

What's worth noticing is who does the checking. Instead of grading its own homework with more reasoning, the agent hands its work to software that already knows the physics and gets back a pass or a fail. Siemens says one of its tools now finishes a characterization job more than ten times faster and uses five to ten times fewer tokens. Those are vendor figures for a very specific workload, so read them as a direction rather than a promise.

Chip design is a long way from a support queue. The pattern travels anyway.

Why this matters to your business

Most of what a support agent gets wrong is checkable. It quotes a refund of $48 when the order system says $42, or promises delivery on Thursday when the carrier says Monday, or cites a returns window your policy changed in March. None of those is a matter of judgment. Each one has a right answer sitting in a system you already own.

When those errors reach a customer, you pay twice. Once to fix the case, and again when the customer quotes the wrong number back at your team as a commitment. And the usual response, putting a person in front of every reply, throws away most of the speed you bought the agent for.

A person holds a bank card and paper receipts over an open laptop keyboard
The customer will compare the reply to the receipt. The agent should get there first.

Why this is a CX-Builder use case

A self-checking support agent is a flow with a second step after the draft. The agent writes its reply and also lists, in a fixed structure, the facts it relies on: the amount, the date, the policy it quoted. Each of those facts then gets checked against the system that owns it. Your order system confirms the amount, the carrier's tracking confirms the date, and your policy library confirms the clause exists and says what the agent claims.

When everything matches, the reply goes out. A mismatch sends the correct figure back to the agent for one more try, and when that fails too, the case goes to a person with the mismatch already highlighted. That last part matters: your reviewers stop reading every reply and start seeing only the ones where the records and the draft disagree.

This is a different job from a human approval gate on high-value actions. The gate decides what an agent may do. The check catches what it got wrong. You want both, and the check is what keeps the gate's queue short.

A customer support representative wearing a headset works at a desk in an office
Reviewers see the cases where the draft and the records disagree, not every reply.

What this looks like if you build it

In CX-Builder it is one agentflow. A structured output step turns the draft's claims into named fields. Tool calls fetch the same fields from your order, shipping and policy sources, with retrieval over the policy documents for anything written in prose. A condition node compares the two, a loop sends mismatches back to the agent with a hard limit on retries, and a human-in-the-loop step catches whatever is left.

The checks are ordinary lookups, so they cost almost nothing next to the model call they protect.

The takeaway

Pull twenty replies your agent sent last month and list every number, date and policy it stated. For each one, name the system that could have confirmed it. Those systems are your verification step, and the facts they cover are the errors your customers stop seeing once the agent has to check them first.

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