This article integrates the latest developments regarding the Ad Context Protocol (AdCP) and live Agentic Transaction data. The landscape is evolving rapidly and this document will be updated as new details emerge.
Open Questions To Tackle
How will AI agents actually communicate in advertising ecosystems?
Can shared protocols like AdCP prevent fragmentation across agentic systems?
What does it look like on the ground for sellers and buyers right now?
What’s the economic tipping point where agentic automation becomes profitable at scale?
Who ensures neutrality and transparency when machines start negotiating media buys?
Key Takeaways
The industry changed yesterday: The Ad Context Protocol went live, creating the "universal ads API" for AI agents.
Agentic Transactions are live: Sellers are already integrating and clearing transactions through partners like Swivel, Scope3, and others.
AdCP aims to standardize how AI agents in advertising communicate, building a shared "language" for agentic negotiation.
Economic viability matters: agentic AI is powerful but the full-scale automation tipping point is still being reached.
Strategic deployment, not blanket automation, will define early winners in the agentic era.
The OpenRTB Moment of the AI Era Has Arrived
The advertising industry just changed forever—and most people haven't noticed yet.
While many were drowning in spreadsheets, a coalition of 20+ ad tech giants quietly launched the Ad Context Protocol ($\text{#AdCP}$) on October 15, 2025. This isn't a future prediction; it's the end of manual media buying as we know it.
The old way required logging into Google Ad Manager, then Meta, then DV360, all with manual uploads, different formats, and fragmented reporting.
The new way? Natural language to an AI agent: "Find eco-conscious millennials interested in SUVs across CTV platforms in Portugal with 150K budget." The agent searches EVERY connected platform simultaneously, compares inventory and audience fit in seconds, and activates campaigns across multiple platforms with ONE command. This is what Brian O'Kelley (founder of AppNexus, now leading this initiative) calls "the universal ads API."
The advertising infrastructure you spent years mastering? It just became middleware. AdCP is the OpenRTB moment for the AI era.
A New Language for the Agentic Era
A new technical standard is emerging in the ad tech landscape. The Ad Context Protocol (AdCP) isn’t promising to fix everything overnight, but it tackles a real challenge: How do AI agents communicate in advertising?
At its core, AdCP is an open-source communication protocol that lets AI agents, whether built by advertisers, publishers, or ad tech platforms, interact using a common language. Think of it as defining the vocabulary and grammar for machines to negotiate advertising transactions.
Built on Anthropic’s Model Context Protocol (MCP) and other agent-to-agent (A2A) frameworks, AdCP standardizes how machines exchange structured data about audiences, inventory, and campaign objectives. If OpenRTB standardized real-time bidding, AdCP aims to standardize agentic negotiation, the collaborative planning and pre-buy conversations that happen outside the bidstream.
The timing reflects where the industry is heading. As AI-driven automation accelerates, the risk of fragmentation grows. Without shared infrastructure, we could face a landscape of disconnected agent systems. As Brian O’Kelley (Scope3) noted at the recent Prebid Summit, AdCP’s potential mirrors what header bidding did years ago: a foundational shift in how systems interact.
The Ground Truth: Seller Participation in Agentic Transactions
Agentic transactions aren't just theoretical; they are live and generating revenue. Following two weeks of wall-to-wall calls with publishers, a series of common questions have emerged about the operational reality of selling agentically:
Getting Started and Integration
- How do I get set up to sell agentically? If you are an existing Swivel client using the SpringServe (now part of Magnite) adserver, the integration is live, and activation takes less than an hour. Swivel will be live in FreeWheel by EOY, Publica by IAS in Q1, followed by GAM and Kevel.
- Who are the buyers? Scope3 is the first mover with a variety of agency partners. We estimate five active agentic buyers will be transacting through year-end.
- What transparency do I have about the buyer agent and the brand? 100% transparency. You see the buyer agent upfront, and the brand through the media brief proposal phase. A human-in-the-loop approves the buy as well as the creative up front.
Inventory and Data Exposure
- What can I expose to seller agents? Sellers can expose a range of things that generally wouldn't flow through the bid stream. This includes first-party data like ACR data or transaction history for a Retail Media Network (RMN). Show level data, content, and context, as well as a full range of traditional and custom inventory are exposed.
- Is there a risk of data leakage? No. Because a seller agent doesn't store or process data, and only uses targeting inside a seller ad platform, traditional issues like data leakage or sharing sensitive information to a DSP are moot. Data and targeting information never leaves the confines of a seller's first-party ad platforms.
- What is an ad product? An ad product is either a static or dynamic combination of inventory, audience, content/context, and price.
Economics and Control
- What are the economics of an agentic transaction? Sellers can clear through the partner (like Swivel) or directly with the buyer for a single-digit transaction rate.
- How do I price an ad product? An ad product can have fixed pricing, dynamic pricing based on audience size, and obey specific rules based on buyer, brand, or category.
- Can I pause or change an agentic buy? Yes. All of the controls that exist in your ad server for a direct campaign exist in an agentic transaction. Changing targeting is theoretically possible but, like a direct buy, may violate the proposal and lead to a paused campaign without the buyer's consent.
How AdCP Fits with Existing Systems
Crucially, AdCP doesn’t aim to disrupt what already works. It’s designed to complement, not replace, OpenRTB. Publishers and platforms can run both OpenRTB and AdCP simultaneously, as they’re not mutually exclusive.
In practical terms, this means:
- Buyer and seller agents can exchange deal criteria directly, forming the "media brief proposal phase" mentioned by sellers.
- Direct campaigns can run inside publisher ad servers or curated marketplaces, aligning with the "ad product" definition.
- Platforms can adopt AdCP incrementally, with no need to rebuild tech stacks.
It’s an additive layer, expanding capacity rather than forcing reinvention.
The Economics of Agentic AI
Agentic AI is compelling, but it isn’t cheap. The numbers that should wake you up are clear: an estimated 80% of digital media buys will be directed by AI agents by 2030. However, the economics matter today. Running an AI agent to optimize campaigns or generate insights has a real computational cost.
That’s why AdCP and MCP are valuable now as bridges for high-value, low-frequency tasks like strategic planning, anomaly detection, and reporting, while we wait for compute economics to catch up.
The smartest players are being selective. They’re mapping workflows to where agentic automation provides clear ROI, often in the strategic planning and high-touch deal negotiation phases that AdCP targets.
Governance, Neutrality, and Transparency
Founding members include Yahoo, PubMatic, Magnite, Scope3, Swivel, and others, showing balanced representation. To ensure neutrality, AdCP will be open-source and governed by a forthcoming non-profit, echoing Prebid’s open contribution framework.
If AI agents negotiate and execute media buys, how can humans trust the process? AdCP addresses this by embedding auditability and bias control. Because it’s open source, implementations must maintain:
- Clear audit trails
- Data provenance and identity transparency
- Support for human-in-the-loop oversight (aligning with the required human approval in the seller Q&A).
In fact, by eliminating opaque bid streams and intermediary layers, AdCP may increase transparency compared to current programmatic systems.
What It Means in Practice
The shift from manual to agentic isn't coming—it arrived yesterday.
For publishers, this means simplified workflows, fewer intermediaries, and greater control over inventory exposure and deal terms via explicit ad products and direct negotiation with verified buyer agents.
The protocol is now publicly available at adcontextprotocol.org. Its success hinges on broad, balanced adoption across supply and demand.
The real skill in this moment isn’t just building AI; it’s knowing where and when to deploy it profitably.
Agentic AI will transform advertising. The open question is: When will the economics align for widespread adoption, and who will be ready when they do?
Our Perspective at MMT
At MMT, we see AdCP as the kind of foundational infrastructure that will define how agentic systems interact in advertising.
We’re actively exploring how to integrate it within our media operations platform, and we welcome collaboration from partners who share that vision.
The real skill in this moment isn’t just building AI; it’s knowing where and when to deploy it profitably.
Agentic AI will transform advertising. The open question is:
💡 When will the economics align for widespread adoption, and who will be ready when they do?
Interested in discussing how AdCP and agentic AI could shape your media operations?
👉 Reach out to us. We’re engaging actively with these developments and eager to explore what they mean for the industry’s future.
