What is Agent-to-Agent Advertising?

Agent-to-agent advertising is a way of transacting media in which a buyer's AI agent and a seller's AI agent communicate directly, exchanging inventory details, questions and deal requests under rules and approvals set by each side.

Also known as: A2A advertising, agent-to-agent media buying

How it works

In traditional direct buying, a buyer emails a seller, receives a proposal, negotiates and then sets up a deal. In programmatic buying, machines handle the auction but people still do most of the discovery and deal setup. Agent-to-agent advertising moves part of that conversation to software on both sides.

A simple exchange might look like this:

  1. A buyer agent sends a structured request: markets, formats, audience or content signals, dates and deal type.
  2. A seller agent answers with matching inventory, prices and availability that the seller has chosen to expose to that buyer.
  3. The buyer agent asks follow-up questions or narrows the request.
  4. Once the buyer side approves, the buyer agent requests a deal and the seller agent returns a Deal ID for activation.

For this to work, both agents need a shared language. Some of that comes from general AI protocols. IAB Tech Lab's AAMP page names "MCP from Anthropic, and Google's Agent to Agent" as key agentic protocols, and states that "the Agentic ecosystem will start with a Buyer Agent and Seller Agent talking to each other" (IAB Tech Lab, AAMP). The same page lists an Agent Registry intended to provide "neutral agent transparency and accountability across the ecosystem." These efforts are ongoing, so expect the details to change.

Why it matters

The biggest benefit is speed on repetitive back-and-forth. Questions that take days of email can be answered in structured exchanges, and both sides get a clear record of what was asked and offered.

Trust is the main open question. A seller needs to know which buyer agent it is talking to and whether it is authorized. A buyer needs to know the seller agent really represents the inventory it describes. Existing supply chain tools such as sellers.json and ads.txt still matter, and new approaches such as agent registries are being explored to fill the gaps.

Example

Illustrative example. An agency's buyer agent is preparing a back-to-school campaign. It asks a representation partner's seller agent for family and education content on web and app in two markets. The seller agent returns three packages. The buyer agent asks whether one package is available as programmatic guaranteed, the seller agent confirms availability and price, and after the agency planner approves, the deal is requested and a Deal ID is returned for the agency's trader to activate.

IncrementX perspective

At IncrementX, the building blocks for agent-to-agent work start with Seller Agent. Authorized buying agents can already use it to discover represented inventory and initiate deal creation, receiving Deal IDs for activation through supported buying platforms.

Wider agent-to-agent buying workflows are being built with partners as part of Agentic Buying. These are future-facing and not a finished integration, and IncrementX's role remains that of a representation partner looking after the interests of the media owners it represents.