Published: 17 September 2026

TL;DR: In conventional programmatic, there is no single document both parties agreed before the campaign ran. In agentic advertising, the bilateral DealSheet is written at negotiation time, timestamped, and held by both parties independently. This piece explains what a verifiable deal record is, what "verifiable" means in this context, and what buyers need to have in place to use one.

Reconciliation has always been one of programmatic advertising's persistent operational difficulties. Buyers and publishers frequently finish a campaign holding different numbers. The delivery data on the buy side does not match the delivery data on the sell side. The gap is real, but establishing what was originally agreed is difficult because the agreed terms were never written into a document both parties hold.

Agentic advertising changes this. The DealSheet, written at negotiation time and held by both parties, is the mechanism that makes a verifiable deal record possible.

The Problem in Conventional Programmatic

In a conventional programmatic transaction, the path from buyer intent to impression delivery passes through multiple systems. The buyer sets a campaign in the DSP. The DSP bids in an auction. The SSP accepts or rejects the bid. An impression fires. Each system generates its own logs.

At no point in this process does a single shared document exist that captures what the buyer and publisher agreed before delivery began. The buyer has DSP logs. The publisher has SSP logs. The marketplace has its own records. None of these documents is the same. All three were generated by different systems, at different points, controlled by different parties.

When a buyer wants to verify what was agreed, they cannot point to a document both parties signed. They can only request records from each platform and attempt to reconcile them. This process is slow, contested, and dependent on the goodwill of parties who may have an interest in the outcome.

What a Verifiable Deal Record Requires

A verifiable deal record has three structural properties.

Written before delivery is the first. The record must be created at the moment of agreement, before any impression is served. A record reconstructed from post-campaign logs is not pre-delivery evidence. It is a reconstruction, and reconstructions can be challenged on the grounds that they were shaped by knowledge of what actually happened.

Held by both parties independently is the second. If only one party holds the record, or if only one party can retrieve it, the record is not bilateral. A DealSheet held only by the marketplace is better than nothing, but it still requires the buyer to trust the marketplace to provide accurate retrieval. A DealSheet held by both parties independently means either party can retrieve their copy without relying on the other party or the marketplace.

Timestamped at the moment of agreement is the third. The timestamp establishes that the record predates delivery. It is the evidentiary anchor. Without a timestamp, it is not possible to demonstrate that the record was written before the campaign ran rather than after.

A DealSheet produced through the Alkimi marketplace has all three properties. It is written when agents reach agreement, timestamped at that moment, and held by both the buy-side and sell-side agents independently.

What "Verifiable" Means

Verifiable does not mean perfect. A verifiable deal record establishes what was agreed. It does not guarantee that delivery matched the agreed terms. Delivery can still fall short, inventory can still depart from agreed scope, and disputes can still arise.

What the verifiable deal record does is change the basis of the dispute. Instead of two parties arguing about what was agreed, they are arguing about whether delivery matched what was clearly agreed. The DealSheet is the reference point. The dispute becomes a question of measurement, not a question of memory or interpretation.

This is a significant operational improvement. Disputes about what was agreed are often irresolvable because neither party has stronger evidence than the other. Disputes about whether delivery matched a written record are resolvable because the record is there.

What Buyers Need to Have in Place

To receive and hold a DealSheet, a buyer needs three things.

An agentic advertising setup is the first. The buyer must have a buy-side agent operating under a mandate. The DealSheet is produced by agent-to-agent negotiation. A buyer running conventional programmatic through a DSP does not produce a DealSheet.

AdCP-compliant infrastructure is the second. The buy-side agent must communicate through the AdCP, published by AgenticAdvertising.org. AdCP compliance is what ensures the agent's proposals can be parsed by sell-side agents and that the deal record produced is in a format both parties can use.

A marketplace connection is the third. The buyer must connect their buy-side agent to a neutral marketplace that provides DealSheet storage and retrieval. Not all marketplaces do this. Buyers should confirm that the marketplace they use writes the deal record to a format accessible to the buyer independently, not only to marketplace systems.

With these three elements in place, a buyer operating through Alkimi will receive a DealSheet for every deal their agent negotiates. That DealSheet is their verifiable record of what was agreed.