Standards & Protocols Reference

AdCP / Advertising Context Protocol.

A practical guide to the open protocol layer for agentic advertising workflows: discovery, planning, buying, creative, signals, governance, accounts, and measurement.

AdCP gives advertising agents a shared task and schema layer. It helps buyers, sellers, platforms, data providers, and creative systems communicate through standardized advertising actions rather than bespoke dashboard workflows and one-off integrations.

AdCP Protocol Stack — agents on top, a governed task layer at the centre, transport, discovery and execution surfaces below. PROTOCOL STACK AdCP Protocol Stack Buyer, seller and operator agents — the actors that initiate and fulfil tasks across the stack. ACTORS Buyer · seller · operator agents The AdCP task layer — the one standard surface where work is named, run and governed. This is the heart of the stack. TASK LAYER AdCP — the task layer Media Buy — an AdCP task family exposed through the same discoverable, governed interface. Media Buy Creative — an AdCP task family exposed through the same discoverable, governed interface. Creative Signals — an AdCP task family exposed through the same discoverable, governed interface. Signals Accounts — an AdCP task family exposed through the same discoverable, governed interface. Accounts Brand — an AdCP task family exposed through the same discoverable, governed interface. Brand Governance — an AdCP task family exposed through the same discoverable, governed interface. Governance Sponsored Intelligence — an AdCP task family exposed through the same discoverable, governed interface. Sponsored Intelligence Transport — AdCP rides existing agent protocols (MCP and A2A) rather than inventing a new wire format. TRANSPORT MCP · A2A Discovery and identity — adagents.json, brand.json and a registry let agents find and trust each other before any task runs. DISCOVERY & IDENTITY adagents.json · brand.json · registry Execution surfaces — the systems AdCP tasks actually drive: publisher, SSP, DSP, creative system, data provider and measurement. EXECUTION SURFACES publisher · SSP · DSP · creative system · data provider · measurement Governance rail — the controls that hold across every layer: approval, idempotency, signatures, audit and human judgment. GOVERNANCE approvalidempotencysignaturesaudithuman judgment AdCP is the task layer — discoverable, executable, governable, auditable.
AdCP sits over MCP / A2A transport: a task layer above execution surfaces, with a governance rail.

AdCP is not a replacement for OpenRTB, clean rooms, or human judgment. It is a protocol layer for making advertising work discoverable, executable, governable, and auditable by agents.

Standard readiness (validate before build)
  • AdCP 3.0 GA · v3.0.16
  • AdCP 3.1 RC.14
  • v2 deprecates Aug 1, 2026
  • Sponsored Intelligence experimental

Fast read

What it is
An open agentic advertising protocol that defines domain-specific tasks and schemas for advertising agents.
What it does
Helps agents discover inventory, set up accounts, buy media, manage creative, activate signals, apply governance, and report results through standardized calls.
What it is not
Not a media exchange, identity graph, DSP, SSP, clean room, or replacement for OpenRTB.
Why it matters
Agentic workflows need repeatable, machine-readable actions. Without a shared protocol, every agent has to learn every platform separately.
Current state
AdCP 3.0 has reached general availability (current patch v3.0.16); 3.1 is in release-candidate validation (currently v3.1.0-rc.14). Validate implementation details against current official docs.
Best next step
Understand the domains, then decide which workflow your company should expose or consume first.
Definition

What AdCP is.

AdCP is a shared advertising task layer for AI agents. It defines what agents can ask for, what systems should return, and how actions move through the advertising workflow.

LayerJobExample
TransportCarries messagesMCP / A2A
AdCPDefines advertising tasks and schemasget_products, create_media_buy, get_signals, activate_signal
Execution systemPerforms the actionpublisher, SSP, DSP, creative system, data provider
GovernanceControls authority and auditapprovals, signatures, idempotency, audit logs
Existing ad standardsPower underlying objects and transactionsOpenRTB, AdCOM, OpenDirect, Deals API
Rationale

Why AdCP exists.

  • Fragmented workflows

    Media buying, creative, data activation, accounts, and reporting still live across disconnected systems and dashboards.

  • Agents need actions, not screens

    An agent cannot scale by clicking through every platform UI. It needs task-level interfaces.

  • Common schemas reduce ambiguity

    Natural-language briefs need to resolve into structured, auditable requests.

  • Human oversight needs architecture

    Agentic buying requires approvals, limits, audit logs, and accountability built into the flow.

  • Platform participation needs standards

    Publishers, data providers, creative systems, and ad platforms need a shared way to expose what agents are allowed to do.

Version watch

AdCP 3.1 RC watchlist.

3.0 is the current general-availability line; 3.1 is in release-candidate validation. Separate what is confirmed from what to validate and what to watch.

Release candidate · validate before build

Confirmed from official docs

  • AdCP 3.0 has reached general availability — current patch v3.0.16 (June 14, 2026); v2 is fully deprecated on August 1, 2026 (UTC).
  • v3.0.16 backports compliance-storyboard fixes and adds a required seller_agent_url field on context_match_request.
  • AdCP 3.1 is in release-candidate validation — current pre-release v3.1.0-rc.14, described as additive over 3.0.
  • A required idempotency_key on every mutating request; RFC 9421 HTTP Message Signatures (optional in 3.0, required for AdCP Verified).
  • One stated 3.1 breaking change: typed enums + ISO 3166-1 country codes for trademark fields.

Validate before implementation

  • Schema version and exact task names
  • Protocol domain changes and MCP / A2A transport assumptions
  • Security / signing and governance-task requirements
  • Registry / discovery and signals-protocol changes
  • Compatibility with 3.0; deprecations or breaking changes; certification implications

Watch next

  • 3.1 GA date and final scope; wire-version transition from "3.1-rc.14" to "3.1"
  • AdCP Verified independent auditing (self-attested in 3.0)
  • Signals-protocol maturity, registry adoption, and creative-generation workflows
  • Measurement / event reporting, SDKs, and reference implementations
  • Curation — listed as "coming soon," not yet a protocol domain
From the implementer seat

Contributions to the protocol.

This page is written from inside the work: No Fluff Advisory builds and operates a live AdCP signals agent (listed in the AAO registry) with all-pass runs on the 3.0 GA and 3.1.0 release-candidate storyboard suites, and contributes upstream in the Signals & Measurement working group.

Merged into the protocol & tooling

  • last_updated on signal-definition — schema field for verifiable signal-record freshness (#5248PR #5249, in the 3.1.0 line since rc.7).
  • Compliance-grader fix — all-pass single-protocol runs rendered “Degraded” by a rollup regression; root-caused to the introducing commit, filed (#5429, triaged P0) and fixed (PR #5444, merged).
  • RFC 9421 webhook-signing default — the inventory (#4270) and draft PRs (#4273/#4275, closed in favor of the maintainer implementation) that drove the 3.0.9 realignment away from the deprecated HMAC framing.

Conformance suite, hardened

  • Signals-only agents now skip non-applicable media-buy gating and gained dedicated error-handling / schema-validation storyboards (#2916, #3350, #4009 — fixed in the 3.1.0 suite; earlier #2535, #3999, #4065).
  • Shaped in review — the signal-definition epistemic / provenance layer (#5017, maintainer-authored): contributed the implementer wire-size data (88 KB for 5 signals vs the 64 KB probe ceiling) that drove the progressive-disclosure design, plus field-level schema review.

Open proposals

  • Runtime attestations RFC — verifier-signed signal-quality evidence on check_governance (#5418; issue titled for 3.1, the posted RFC proposes it as a 3.2 candidate).
  • revoke_activation revocation primitive (#4203) · Measurement Feedback Signal (#4296).
  • RFC 9421 migration coordination (#4205) · JWKS adoption baseline (#4206).

Contribution statuses validated June 2026 against the public AdCP repository; open proposals are point-in-time and may merge, change, or close. Maintainer-authored work is credited as review influence, not authorship.

Domains

Protocol domains.

AdCP organizes work into domain-specific tasks and schemas. Task names below are drawn from current official documentation.

  • Media Buy

    Inventory discovery, campaign creation, delivery reporting.

    get_products · create_media_buy · get_media_buy_delivery

  • Creative

    Creative format discovery, building, preview, distribution.

    build_creative · preview_creative · list_creative_formats

  • Signals

    Audience and contextual data discovery and activation.

    get_signals · activate_signal

  • Accounts

    Commercial identity, billing, and usage reporting.

    list_accounts · sync_accounts · report_usage

  • Governance

    Brand suitability, approval, policy, audit, content standards.

    create_content_standards · calibrate_content

  • Brand

    Machine-readable brand identity and authorized agents via brand.json.

    brand.json discovery

  • Sponsored Intelligence

    Conversational brand experiences on AI platforms.

    Experimental surface in AdCP 3.0

  • Curation

    Media inventory curation.

    Listed "coming soon" — not a current domain

AdCP Protocol Domains — one hub, seven domains, one shared schema. AdCP PROTOCOL DOMAINS Media Buy — discover inventory, transact, and report on delivery through one schema. Media Buy discover · buy · report Creative — assemble and preview ad creative against the same shared schema. Creative build · preview Signals — discover audience and context signals and activate them on a buy. Signals discover · activate Accounts — billing, usage, and entitlements for every party on the protocol. Accounts billing · usage Governance — approval workflows and an auditable trace across every domain. Governance approve · audit Brand — a brand.json declares brand identity and guardrails the protocol can read. Brand brand.json Sponsored Intelligence — an experimental domain, not yet a stable part of the schema. Sponsored Intelligence experimental exp. AdCP — the single protocol every domain shares; one schema runs across all of them. PROTOCOL AdCP One protocol, many domains — the same schema across every step.
AdCP at the center; each domain connects to a workflow surface.
Workflow

From brief to governed execution.

  1. Discover authorized agents — adagents.json, brand.json, registry
  2. Set up account context — commercial identity, billing, advertiser / operator relationship
  3. Discover inventory and products — natural-language brief into structured product responses
  4. Build or sync creative — formats, assets, brand identity, approvals
  5. Add signals — audiences, suppression, contextual signals, signal activation
  6. Check governance — budget, brand safety, targeting rules, approvals
  7. Execute, report, and audit — media buy, delivery, events, audit logs
From brief to governed execution — seven steps, brief in, audited execution out. BRIEF → GOVERNED EXECUTION Discover agents — read adagents.json and the registry to find which agents can act for this brand. 01 Discover agents adagents.json · registry Account context — resolve identity and billing so the brief runs against the right account. 02 Account context identity · billing Discover products — turn the natural-language brief into a structured product schema. 03 Discover products brief → schema Build / sync creative — assemble formats and route them through approvals. 04 Build / sync creative formats · approvals Add signals — attach audiences and activation signals to the campaign. 05 Add signals audiences · activation Check governance — verify budget, brand safety, and approvals before anything spends. 06 Check governance budget · brand safety Execute, report, audit — run delivery, emit events, and keep an auditable log of every action. 07 Execute, report, audit delivery · events · logs Natural-language brief in, governed + audited execution out.
Brief → discovery → accounts → products → creative → signals → governance → buy / report / audit.

Discovery starts from two machine-readable files — a publisher's adagents.json (who may sell its inventory) and a brand's brand.json (who may act for the brand, and how):

adagents.json illustrative
{
  "publisher": "example-publisher.com",
  "authorized_agents": [
    {
      "url": "https://sales-agent.example-ssp.com",
      "role": "seller",
      "properties": ["news", "sports"]
    }
  ],
  "signing_keys": [
    { "kid": "2026-key-1", "alg": "Ed25519" }
  ]
}
brand.json illustrative
{
  "brand": "example-brand.com",
  "display_name": "Example Brand",
  "authorized_agents": [
    { "url": "https://agent.example-buyer.com", "role": "buyer" }
  ],
  "identity": {
    "logos": ["/brand/logo.svg"],
    "colors": ["#1a1a1a", "#4a5a2e"],
    "tone": "confident, plain-spoken"
  },
  "policy": { "restricted_categories": ["gambling", "politics"] }
}
Signals

Signals: where AdCP meets signal containerization.

The signals layer is where AdCP becomes especially important for agentic advertising. Agents need to discover signals, understand what they mean, check provenance and policy, activate them, and monitor status. That is the same operating problem behind signal containerization — turning audience logic into a governed, executable object.

  • Discover

    What signals exist and what do they mean?

  • Inspect

    Where did the signal come from, how fresh is it, and what policy applies?

  • Activate

    Where can the signal run: seller, platform, identity path, contextual path, or measurement layer?

  • Monitor

    What is the activation status and what outcome did it improve?

Signals: a governed object — discover, inspect, activate, monitor. SIGNAL LIFECYCLE Discover — find which signals exist and what each one actually means before you reach for it. 01 Discover what signals exist what they mean Inspect — interrogate provenance, freshness, and policy so you trust the object before activating it. 02 Inspect provenance · freshness policy Activate — put the signal to work across an identity path, a contextual path, and measurement. 03 Activate identity path · contextual path · measurement Monitor — watch live status and the realised outcome, then feed it back into discovery. 04 Monitor status outcome the same operating problem as signal containerization Discover, inspect, activate, monitor — signals as executable objects.
Discover, inspect, activate, monitor — signals as executable objects.

An agent discovers signals with a natural-language brief, then activates the chosen signal to a destination — a single get_signals call rather than a taxonomy lookup:

get_signals (MCP tool call) illustrative
{
  "tool": "get_signals",
  "arguments": {
    "brief": "in-market for premium CTV, US households, privacy-safe",
    "deliver_to": { "platform": "dsp", "account": "acct_123" },
    "max_results": 10
  }
}
Trust

Governance is the trust layer.

Agentic advertising only works if actions are accountable. A protocol needs to know who called a tool, what authority they had, what was approved, what conditions applied, and what actually ran.

  • Human-in-the-loop approvals (a three-party separation of duties)
  • Idempotency keys on every mutating request
  • Request signing (RFC 9421 HTTP Message Signatures)
  • Correlated audit logs
  • Governance checks and signed governance tokens
  • Brand-safety and content-standard enforcement
  • Budget thresholds and authority / role boundaries

The principle

Human judgment is embedded in the system design, not bolted on afterward — the human stays the locus of accountability.

Complementarity

Where AdCP fits with IAB Tech Lab standards.

AdCP is best understood as an agentic management and workflow layer. IAB Tech Lab's AAMP work extends existing standards with agentic foundations, protocols, and trust infrastructure; ARTF focuses on containerized real-time execution; Agentic Audiences on embedding-based signal exchange. These layers can be complementary with clear boundaries. See the IAB Agentic Standards guide.

InitiativeRoleBest question
AdCPAgent task / workflow languageWhat should the agent ask or do?
AAMPIAB Tech Lab umbrella for agentic advertising standardsHow do agentic foundations, protocols, and trust fit into existing standards?
ARTFContainerized real-time execution frameworkHow can service agents run inside host infrastructure with low latency and controlled mutation?
Agentic AudiencesEmbedding-based signal exchangeHow do agents exchange identity, contextual, and reinforcement signals?
OpenRTB / AdCOM / Deals API / OpenDirectExisting transaction and object standardsWhat underlying objects and transaction models should agentic systems reference?
Complementary layers — AdCP's workflow layer and IAB Tech Lab's standards/runtime layer compose into one interoperable stack. COMPLEMENTARITY MAP AdCP — the agent task and workflow layer: what an agent does (discover, buy, creative, signals, govern, report), independent of any single runtime. AdCP Agent task & workflow discover buy creative signals govern report IAB Tech Lab — the standards and runtime layer: the umbrella (AAMP), the runtime (ARTF), the signal exchange (Agentic Audiences) and the open foundations agents run on. IAB TECH LAB Standards & runtime AAMP umbrella ARTF runtime Agentic Audiences signal exchange FOUNDATIONS OpenRTB · AdCOM Deals API · OpenDirect Agentic advertising interoperability — the shared outcome both layers serve: tasks expressed once run across open standards and runtimes. SHARED OUTCOME Agentic advertising interoperability Not a winner-takes-all — a workflow layer and a standards / runtime layer.
A workflow layer and a standards / runtime layer, meeting at agentic advertising interoperability.
Implementation

Implementation lens by company type.

Pick your company type to see what to expose or consume — and the AdCP domains it touches first.

Select your company type
What to expose

Authorized agents, inventory products, packages, account setup, governance, reporting.

  • adagents.json
  • Media Buy
  • Accounts
  • Governance
What to consume

Partner discovery, product discovery, creative formats, media buy, governance, reporting.

  • brand.json
  • Media Buy
  • Creative
  • Signals
What to expose

Signal catalog, provenance, activation paths, pricing, policy, status.

  • Signals
  • Accounts
  • Governance
What to support

Seller agents, deals, signals, governance, a real-time execution bridge, reporting.

  • Media Buy
  • Signals
  • Governance
  • registry
What to support

Buyer agents, media buys, creative, signal activation, governance, measurement.

  • Media Buy
  • Creative
  • Signals
  • Governance
What to expose

Formats, asset generation, preview, brand identity, approval workflow.

  • Creative
  • Brand
  • Governance
What to expose

Delivery, event logging, attribution, audit, lift, governed outputs.

  • Media Buy
  • Accounts
  • Governance
No Fluff POV

A protocol defines the task. It does not replace judgment.

The industry should avoid treating AdCP as a magic layer that makes agents safe by default. The protocol can define the task. It cannot replace commercial judgment, governance design, data rights, measurement discipline, or operating ownership.

  • Start with one workflow, not every workflow.
  • Expose the safest useful task first.
  • Design governance before spend movement.
  • Treat signals as governed objects, not just segment IDs.
  • Build audit and status from day one.
  • Connect protocol work to business outcomes, not demos.
Stack fit

Where this fits in the full standards stack.

The layer map

AdCP defines the agent workflow layer. It still needs transaction rails, privacy constraints, measurement trust, and evidence discipline around it.

Next step

Building around AdCP or agentic advertising standards?

Use the playbooks to map the workflow, governance, signal model, implementation path, and commercial productization before building against the spec.