AdCP

Discover a seller’s protocol support and capabilities across all AdCP protocols. This is the first call a buyer should make to understand what a seller supports. Response Time: ~2 seconds (configuration lookup) Purpose:

AdCP discovery - Does this agent support AdCP? Which versions?
Protocol support - Which domain protocols (media_buy, signals, governance, sponsored_intelligence, creative)?
Auth model - Does this seller trust the agent directly, or must each operator authenticate independently?
Detailed capabilities - Features, AXE integrations, geo targeting, portfolio

Request Schema: /schemas/v3/protocol/get-adcp-capabilities-request.json Response Schema: /schemas/v3/protocol/get-adcp-capabilities-response.json

Tool-Based Discovery

AdCP uses native MCP/A2A tool discovery. The presence of get_adcp_capabilities in an agent’s tool list indicates AdCP support.

Discovery Flow:
Browse agent's tool list (MCP) or skills (A2A)
See 'get_adcp_capabilities' tool → Agent supports AdCP
Call get_adcp_capabilities → Get version, protocols, features, capabilities
Proceed based on returned capabilities

This approach:

Uses standard MCP/A2A mechanisms (no custom extensions)
Always returns current capabilities (not stale metadata)
Single source of truth for all capability information

:::note The agent card extension (adcp-extension.json) has been removed in v3. Use tool-based discovery instead. :::

Request Parameters

Field	Type	Description
`protocols`	string[]	Optional. Filter to specific protocols (`media_buy`, `signals`, `governance`, `sponsored_intelligence`, `creative`). If omitted, returns all supported protocols.

Response Structure

Core AdCP protocol information:

Field	Type	Description
`major_versions`	integer[]	Required. AdCP major versions supported (e.g., `[1]`)

supported_protocols

Array of domain protocols this seller supports:

{
  "supported_protocols": ["media_buy"]
}

account

Account and authentication capabilities. All sellers should declare this section — buyers read it before calling sync_accounts, list_accounts, or any authenticated task. Even simple publishers need account management to handle billing relationships and sandbox testing.

Field	Type	Description
`supported_billing`	string[]	Required. Billing models this seller supports: `operator`, `agent`. The buyer must pass one of these values as `billing` in every `sync_accounts` entry.
`require_operator_auth`	boolean	Default: `false`. Determines the account model. When `true` (explicit accounts): each operator authenticates independently, buyer discovers accounts via `list_accounts`, passes `account_id`. When `false` (implicit accounts): agent is trusted, buyer declares accounts via `sync_accounts`, passes natural key (`brand` + `operator`). For sandbox, the path follows the account model: explicit accounts discover pre-existing test accounts via `list_accounts`; implicit accounts declare sandbox via `sync_accounts` with `sandbox: true`.
`authorization_endpoint`	string	OAuth URL for operator authentication. Present when the seller supports OAuth for operator authentication. Relevant when `require_operator_auth: true`; if absent, operators obtain credentials out-of-band (seller portal, API key).
`required_for_products`	boolean	Default: `false`. When `true`, the buyer must establish an account before calling `get_products`. When `false`, the buyer can browse products without an account — useful for price comparison and discovery before committing to a seller.
`account_financials`	boolean	Default: `false`. When `true`, the seller supports `get_account_financials` for querying spend, credit, and invoice status. Only applicable to operator-billed accounts.
`sandbox`	boolean	Default: `false`. Strongly recommended for production sales agents. When `true`, the seller supports sandbox accounts for testing. For sandbox, the path follows the account model: explicit accounts discover pre-existing test accounts via `list_accounts`; implicit accounts declare sandbox via `sync_accounts` with `sandbox: true` — no real platform calls or spend. See Sandbox mode.

Auth models

Implicit accounts (require_operator_auth: false) — The seller trusts the agent’s identity claims. The agent authenticates once with its own bearer token, then calls sync_accounts to declare which brands and operators it represents. The seller provisions accounts based on the agent’s claims, optionally verifying operators against brand.json. All subsequent calls use the agent’s single credential and pass natural keys (brand + operator). Explicit accounts (require_operator_auth: true) — Each operator must authenticate with the seller directly. The agent obtains a credential per operator — via OAuth using authorization_endpoint, or out-of-band — opens a per-operator session, and discovers accounts via list_accounts. The buyer passes seller-assigned account_id values on all subsequent requests. For sandbox, the path follows the account model: explicit accounts (require_operator_auth: true) discover pre-existing test accounts via list_accounts; implicit accounts declare sandbox via sync_accounts with sandbox: true. See Accounts and Agents for full workflows and seller patterns for common combinations of auth model and billing support.

media_buy

Media-buy protocol capabilities. Only present if media_buy is in supported_protocols.

features

Optional media-buy features. If declared true, seller MUST honor requests using that feature.

Feature	Description
`inline_creative_management`	Accepts creatives inline in `create_media_buy` requests
`property_list_filtering`	Honors `property_list` parameter in `get_products`
`content_standards`	Full support for content standards configuration

execution

Technical execution capabilities:

Field	Type	Description
`axe_integrations`	string[]	Agentic ad exchange (AXE) URLs this seller can execute through
`creative_specs`	object	Creative specification support (VAST versions, MRAID, etc.)
`targeting`	object	Targeting capabilities (geo granularity)

creative_specs

Field	Type	Description
`vast_versions`	string[]	VAST versions supported (e.g., `["4.0", "4.1", "4.2"]`)
`mraid_versions`	string[]	MRAID versions supported
`vpaid`	boolean	VPAID support
`simid`	boolean	SIMID support

targeting

Field	Type	Description
`geo_countries`	boolean	Country-level targeting using ISO 3166-1 alpha-2 codes
`geo_regions`	boolean	Region/state-level targeting using ISO 3166-2 codes (e.g., `US-NY`, `GB-SCT`)
`geo_metros`	object	Metro area targeting with system-specific support
`geo_postal_areas`	object	Postal area targeting with country and precision support
`age_restriction`	object	Age restriction capabilities with `supported` flag and `verification_methods`
`device_platform`	boolean	Device platform targeting (Sec-CH-UA-Platform values)
`device_type`	boolean	Device form factor targeting (desktop, mobile, tablet, ctv, dooh)
`language`	boolean	Language targeting (ISO 639-1 codes)
`audience_include`	boolean	Audience inclusion targeting (requires `features.audience_targeting`)
`audience_exclude`	boolean	Audience exclusion targeting (requires `features.audience_targeting`)
`keyword_targets`	object	Keyword targeting with `supported_match_types` array (`broad`, `phrase`, `exact`). Presence indicates support.
`negative_keywords`	object	Negative keyword targeting with `supported_match_types` array. Presence indicates support.
`geo_proximity`	object	Proximity targeting from arbitrary coordinates (see below)

Sellers that support a geographic targeting level SHOULD support both inclusion and exclusion at that level. For example, geo_metros.nielsen_dma: true SHOULD mean the seller supports both geo_metros and geo_metros_exclude with Nielsen DMA codes. If a seller only supports one direction (e.g., inclusion but not exclusion), it MUST return a validation error for unsupported fields rather than silently ignoring them. See Targeting Overlays for exclusion semantics. geo_proximity specifies which proximity targeting methods are supported:

Field	Type	Description
`radius`	boolean	Simple radius targeting (distance circle from a point)
`travel_time`	boolean	Travel time isochrone targeting (requires a routing engine)
`geometry`	boolean	Pre-computed GeoJSON geometry (buyer provides the polygon)
`transport_modes`	string[]	Transport modes supported for isochrones: `driving`, `walking`, `cycling`, `public_transport`

geo_metros specifies which metro classification systems are supported:

System	Description
`nielsen_dma`	Nielsen DMA codes (US market, e.g., `501` for NYC)
`uk_itl1`	UK ITL Level 1 regions
`uk_itl2`	UK ITL Level 2 regions
`eurostat_nuts2`	Eurostat NUTS Level 2 regions (EU)

geo_postal_areas specifies which postal code systems are supported:

System	Description
`us_zip`	US 5-digit ZIP codes (e.g., `10001`)
`us_zip_plus_four`	US 9-digit ZIP+4 codes (e.g., `10001-1234`)
`gb_outward`	UK postcode district (e.g., `SW1`, `EC1`)
`gb_full`	UK full postcode (e.g., `SW1A 1AA`)
`ca_fsa`	Canadian Forward Sortation Area (e.g., `K1A`)
`ca_full`	Canadian full postal code (e.g., `K1A 0B1`)
`de_plz`	German Postleitzahl (e.g., `10115`)
`fr_code_postal`	French code postal (e.g., `75001`)
`au_postcode`	Australian postcode (e.g., `2000`)
`ch_plz`	Swiss Postleitzahl (e.g., `8000`)
`at_plz`	Austrian Postleitzahl (e.g., `1010`)

conversion_tracking

Seller-level conversion tracking capabilities. Declares what the seller supports for kind: "event" optimization goals.

Field	Type	Description
`multi_source_event_dedup`	boolean	Whether the seller can deduplicate events across multiple event sources within a single goal. When `true`, the same `event_id` from multiple sources counts once. When `false` or absent, buyers should use a single event source per goal.
`supported_event_types`	string[]	Event types this seller can track. If omitted, all standard event types are supported.
`supported_uid_types`	string[]	Universal ID types accepted for user matching.
`supported_hashed_identifiers`	string[]	Hashed PII types accepted (`hashed_email`, `hashed_phone`). Buyers must hash before sending (SHA-256, normalized).
`supported_action_sources`	string[]	Action sources this seller accepts events from.
`attribution_windows`	object[]	Available attribution windows. Single-element arrays indicate fixed windows; multi-element arrays indicate configurable options the buyer can choose from via `attribution_window` on optimization goals.

portfolio

Inventory portfolio information:

Field	Type	Description
`publisher_domains`	string[]	Required. Publisher domains this seller represents
`primary_channels`	string[]	Main advertising channels
`primary_countries`	string[]	Main countries (ISO codes)
`description`	string	Markdown portfolio description
`advertising_policies`	string	Content policies and restrictions

signals

Signals protocol capabilities. Only present if signals is in supported_protocols. Reserved for future use.

creative

Creative protocol capabilities. Only present if creative is in supported_protocols.

Field	Type	Description
`supports_compliance`	boolean	When `true`, this creative agent can process briefs with compliance requirements (`required_disclosures`, `prohibited_claims`) and will validate that disclosures can be satisfied by the target format. Use the `disclosure_positions` filter on `list_creative_formats` to find compatible formats.

governance

Governance protocol capabilities. Only present if governance is in supported_protocols. Governance agents provide property data like compliance scores, brand suitability ratings, quality metrics, and sustainability metrics.

property_features

Array of property features this governance agent can evaluate:

Field	Type	Description
`feature_id`	string	Required. Unique identifier (e.g., `mfa_score`, `coppa_certified`)
`type`	string	Required. Data type: `binary`, `quantitative`, or `categorical`
`range`	object	For quantitative: `{ min, max }`
`categories`	string[]	For categorical: valid values
`description`	string	Human-readable description
`methodology_url`	string	URL to methodology documentation

Example governance agent response:

{
  "$schema": "/schemas/3.0.0-rc.2/protocol/get-adcp-capabilities-response.json",
  "adcp": { "major_versions": [1] },
  "supported_protocols": ["governance"],
  "governance": {
    "property_features": [
      { "feature_id": "mfa_score", "type": "quantitative", "range": { "min": 0, "max": 100 }, "description": "Made For Advertising detection (0=quality content, 100=likely MFA)", "methodology_url": "https://vendor.example.com/methodology/mfa" },
      { "feature_id": "coppa_certified", "type": "binary", "description": "COPPA compliance certification" },
      { "feature_id": "carbon_score", "type": "quantitative", "range": { "min": 0, "max": 100 }, "description": "Carbon footprint sustainability score", "methodology_url": "https://scope3.com/methodology/carbon-score" },
      { "feature_id": "content_category", "type": "categorical", "categories": ["news", "entertainment", "sports", "finance"], "description": "Primary content category" }
    ]
  }
}

extensions_supported

Array of extension namespaces this agent supports. Buyers can expect meaningful data in ext.{namespace} fields on responses from this agent.

Field	Type	Description
`extensions_supported`	string[]	Extension namespaces (e.g., `["scope3", "garm"]`)

Extension schemas are published in the AdCP extension registry. When an agent declares support for an extension, buyers know to look for and process ext.{namespace} data in responses. Example:

{
  "extensions_supported": ["scope3", "garm", "iab_tcf"]
}

This tells buyers:

Product responses may include ext.scope3 with Scope3 sustainability data
Creative policies may include ext.garm with GARM brand suitability categorizations
Responses may include ext.iab_tcf with IAB TCF consent data

The Capability Contract

If a capability is declared, the seller MUST honor it.

media_buy.execution.targeting.geo_postal_areas.us_zip: true → Buyer can send US ZIP codes, seller MUST honor them
media_buy.execution.targeting.geo_metros.nielsen_dma: true → Buyer can send DMA codes, seller MUST honor them
media_buy.features.content_standards: true → Seller MUST apply content standards when provided
AXE URL in media_buy.execution.axe_integrations → Seller can execute through that exchange

No silent ignoring. If a seller can’t support a capability, they should declare false or omit it.

Common Scenarios

Basic Capability Discovery

import { AdcpClient } from '@adcp/client';

const client = new AdcpClient({ baseUrl: 'https://seller.example.com/mcp' });

// Get seller capabilities
const result = await client.getAdcpCapabilities({});

if (result.errors) {
  throw new Error(`Request failed: ${result.errors[0].message}`);
}

// Check protocol support
console.log(`AdCP versions: ${result.adcp.major_versions.join(', ')}`);
console.log(`Supported protocols: ${result.supported_protocols.join(', ')}`);

// Check media-buy capabilities
if (result.supported_protocols.includes('media_buy')) {
  const mediaBuy = result.media_buy;

  // Check feature support
  if (mediaBuy.features?.content_standards) {
    console.log('Content standards supported');
  }

  // Check AXE integrations
  if (mediaBuy.execution?.axe_integrations?.includes('https://agentic.scope3.com')) {
    console.log('Scope3 AXE integration available');
  }

  // Check geo targeting
  if (mediaBuy.execution?.targeting?.geo_postal_areas?.us_zip) {
    console.log('US ZIP code targeting supported');
  }

  // Portfolio overview
  console.log(`Publishers: ${mediaBuy.portfolio.publisher_domains.length}`);
  console.log(`Channels: ${mediaBuy.portfolio.primary_channels?.join(', ')}`);
}

Check multi-protocol support

const caps = await client.getAdcpCapabilities({});

const sellsMedia = caps.supported_protocols.includes('media_buy');
const managesCreatives = caps.supported_protocols.includes('creative');

if (sellsMedia && managesCreatives) {
  // Single agent handles both protocols — no need to discover a separate service
  const formats = await client.listCreativeFormats({});
  const delivery = await client.getCreativeDelivery({
    media_buy_ids: ['mb_12345']
  });
}

Filter sellers by capability

// Find sellers that support specific requirements
async function findCompatibleSellers(sellers, requirements) {
  const compatible = [];

  for (const sellerUrl of sellers) {
    const client = new AdcpClient({ baseUrl: sellerUrl });
    const caps = await client.getAdcpCapabilities({});

    if (caps.errors) continue;

    // Must support media_buy protocol
    if (!caps.supported_protocols.includes('media_buy')) continue;

    const mediaBuy = caps.media_buy;

    // Check AXE integration requirement
    if (requirements.axeIntegration) {
      if (!mediaBuy.execution?.axe_integrations?.includes(requirements.axeIntegration)) {
        continue;
      }
    }

    // Check geo targeting requirement
    if (requirements.postalCodeTargeting) {
      if (!mediaBuy.execution?.targeting?.geo_postal_areas?.us_zip) {
        continue;
      }
    }

    // Check feature requirement
    if (requirements.contentStandards) {
      if (!mediaBuy.features?.content_standards) {
        continue;
      }
    }

    compatible.push({ url: sellerUrl, capabilities: caps });
  }

  return compatible;
}

// Usage
const sellers = await findCompatibleSellers(
  ['https://seller1.com/mcp', 'https://seller2.com/mcp'],
  {
    axeIntegration: 'https://agentic.scope3.com',
    postalCodeTargeting: true,
    contentStandards: true
  }
);

Use Capabilities to Build Targeting

Capabilities tell you what you CAN specify in create_media_buy targeting. Use required_geo_targeting to filter products to sellers that support specific geo targeting levels and systems:

// First, check capabilities
const caps = await client.getAdcpCapabilities({});

if (!caps.supported_protocols.includes('media_buy')) {
  throw new Error('Seller does not support media_buy protocol');
}

const mediaBuy = caps.media_buy;

// Filter products to sellers with specific geo targeting capabilities
const products = await client.getProducts({
  brief: "Premium video inventory in US for ZIP-targeted campaign",
  filters: {
    channels: ['olv', 'ctv'],
    countries: ['US'],
    // Require seller supports ZIP targeting (capability filter - no actual ZIPs needed)
    // level = granularity, system = classification taxonomy
    required_geo_targeting: [
      { level: 'postal_area', system: 'us_zip' }
    ],
    // Only include if seller supports this AXE
    required_axe_integrations: ['https://agentic.scope3.com']
  }
});

// Then, create media buy with fine-grained targeting
// (if seller supports postal areas, we can target specific ZIP codes)
const buy = await client.createMediaBuy({
  buyer_ref: 'my-campaign-001',
  brand: { domain: 'mybrand.com' },
  packages: [{
    buyer_ref: 'package-001',
    product_id: products.products[0].product_id,
    pricing_option_id: products.products[0].pricing_options[0].id,
    budget: 10000,
    // Targeting overlay refines delivery within product coverage
    targeting_overlay: {
      geo_countries: ['US'],
      // Only specify ZIP targeting if seller supports it
      ...(mediaBuy.execution?.targeting?.geo_postal_areas?.us_zip && {
        geo_postal_areas: [{
          system: 'us_zip',
          values: ['10001', '10002', '10003', '10004', '10005']
        }]
      })
    }
  }],
  start_time: { type: 'asap' },
  end_time: '2025-03-01T00:00:00Z'
});

Two models for product geography:

Inventory Type	Filter By	Example
Digital (display, OLV, CTV)	Capability: `required_geo_targeting`	Products have broad coverage, target at buy time
Local (radio, DOOH, local TV)	Coverage: `metros`, `regions`	Products ARE geographically bound

Digital inventory: Use countries + required_geo_targeting (capability), apply fine-grained targeting in create_media_buy
Local inventory: Use metros/regions (coverage) to find products with coverage in your target markets

Local Inventory Example (Radio, DOOH)

For locally-bound inventory, products ARE geographically specific. A radio station in NYC DMA only covers NYC.

// Find radio products in specific DMAs
const radioProducts = await client.getProducts({
  brief: "Radio inventory in NYC and LA markets",
  filters: {
    channels: ['radio'],
    // Coverage filter: products must cover these metros
    metros: [
      { system: 'nielsen_dma', code: '501' },  // NYC
      { system: 'nielsen_dma', code: '803' }   // LA
    ]
  }
});

// For local inventory, targeting_overlay is optional -
// the product's coverage IS the geography
const buy = await client.createMediaBuy({
  buyer_ref: 'radio-campaign-001',
  brand: { domain: 'mybrand.com' },
  packages: [{
    buyer_ref: 'package-001',
    product_id: radioProducts.products[0].product_id,
    pricing_option_id: radioProducts.products[0].pricing_options[0].id,
    budget: 5000
    // No targeting_overlay needed - product covers NYC DMA
  }],
  start_time: { type: 'asap' },
  end_time: '2025-03-01T00:00:00Z'
});

Response Example

{
  "$schema": "/schemas/3.0.0-rc.2/protocol/get-adcp-capabilities-response.json",
  "adcp": {
    "major_versions": [1]
  },
  "supported_protocols": ["media_buy"],
  "account": {
    "require_operator_auth": false,
    "supported_billing": ["operator", "agent"]
  },
  "media_buy": {
    "features": {
      "inline_creative_management": true,
      "property_list_filtering": true,
      "content_standards": false
    },
    "execution": {
      "axe_integrations": ["https://agentic.scope3.com"],
      "creative_specs": {
        "vast_versions": ["4.0", "4.1", "4.2"],
        "mraid_versions": ["3.0"],
        "vpaid": false,
        "simid": true
      },
      "targeting": {
        "geo_countries": true,
        "geo_regions": true,
        "geo_metros": {
          "nielsen_dma": true,
          "uk_itl2": false,
          "eurostat_nuts2": false
        },
        "geo_postal_areas": {
          "us_zip": true,
          "us_zip_plus_four": false,
          "gb_outward": true,
          "gb_full": false,
          "ca_fsa": true
        },
        "device_platform": true,
        "device_type": true,
        "language": true,
        "audience_include": true,
        "audience_exclude": true,
        "keyword_targets": {
          "supported_match_types": ["broad", "phrase", "exact"]
        },
        "negative_keywords": {
          "supported_match_types": ["broad", "exact"]
        }
      }
    },
    "conversion_tracking": {
      "multi_source_event_dedup": false,
      "supported_event_types": ["purchase", "lead", "add_to_cart", "view_content"],
      "supported_action_sources": ["website", "app"],
      "attribution_windows": [
        { "post_click": [{ "interval": 7, "unit": "days" }, { "interval": 28, "unit": "days" }], "post_view": [{ "interval": 1, "unit": "days" }, { "interval": 7, "unit": "days" }] }
      ]
    },
    "portfolio": {
      "publisher_domains": ["example.com", "news.example.com"],
      "primary_channels": ["display", "olv"],
      "primary_countries": ["US", "CA"]
    }
  },
  "extensions_supported": ["scope3"],
  "last_updated": "2025-01-23T10:00:00Z"
}

This tells buyers:

AdCP versions: Version 1
Protocols: Media buy only
Auth model: Agent-trusted (require_operator_auth: false) — authenticate once, declare brands via sync_accounts
Billing: Operator or agent billing; default is operator
Country targeting: Available (ISO 3166-1 alpha-2: US, GB, etc.)
Region targeting: Available (ISO 3166-2: US-NY, GB-SCT, etc.)
Metro targeting: Nielsen DMA only (US market)
Postal targeting: US ZIP, UK outward codes, Canadian FSA
Conversion tracking: Accepts purchase, lead, add_to_cart, view_content events from website/app; no multi-source dedup
Extensions: Scope3 sustainability data in ext.scope3

Multi-protocol agent

An agent can implement multiple protocols from a single endpoint. This is common for sellers that manage both media buying and creative generation — the buyer calls all tasks on the same URL.

{
  "$schema": "/schemas/3.0.0-rc.2/protocol/get-adcp-capabilities-response.json",
  "adcp": {
    "major_versions": [3]
  },
  "supported_protocols": ["media_buy", "creative"],
  "account": {
    "require_operator_auth": false,
    "supported_billing": ["operator"]
  },
  "media_buy": {
    "features": {
      "inline_creative_management": true
    },
    "portfolio": {
      "publisher_domains": ["news.example.com"],
      "primary_channels": ["display", "olv"]
    }
  },
  "creative": {
    "has_creative_library": true,
    "supports_generation": true,
    "supports_transformation": false,
    "supports_compliance": false
  }
}

This agent supports:

Media Buy Protocol: Product discovery, media buying, delivery reporting
Creative Protocol: Creative library management, AI-powered creative generation, variant-level delivery analytics via get_creative_delivery
Shared account: A single account established via sync_accounts applies to both protocols

When supported_protocols includes "creative", the buyer can call Creative Protocol tasks (list_creative_formats, sync_creatives, get_creative_delivery, etc.) on this agent. See Creative capabilities on sales agents.

Geo Standards Reference

Level	System	Examples
Country	ISO 3166-1 alpha-2	`US`, `GB`, `DE`, `CA`
Region	ISO 3166-2	`US-NY`, `GB-SCT`, `DE-BY`, `CA-ON`
Metro (US)	`nielsen_dma`	`501` (NYC), `803` (LA), `602` (Chicago)
Metro (UK)	`uk_itl2`	`UKI` (London), `UKD` (North West)
Metro (EU)	`eurostat_nuts2`	`DE30` (Berlin), `FR10` (Île-de-France)
Postal (US)	`us_zip`	`10001`, `90210`
Postal (US)	`us_zip_plus_four`	`10001-1234`
Postal (UK)	`gb_outward`	`SW1`, `EC1`, `M1`
Postal (UK)	`gb_full`	`SW1A 1AA`
Postal (CA)	`ca_fsa`	`K1A`, `M5V`

Migration from list_authorized_properties (v2)

The list_authorized_properties task was removed in v3. If migrating from v2:

Old Field	New Location
`publisher_domains`	`media_buy.portfolio.publisher_domains`
`primary_channels`	`media_buy.portfolio.primary_channels`
`primary_countries`	`media_buy.portfolio.primary_countries`
`portfolio_description`	`media_buy.portfolio.description`
`advertising_policies`	`media_buy.portfolio.advertising_policies`
`last_updated`	`last_updated` (top level)

New fields:

adcp.major_versions - Version compatibility
supported_protocols - Which domain protocols are supported
media_buy.features - Optional feature support
media_buy.execution.axe_integrations - Ad exchange support
media_buy.execution.creative_specs - VAST/MRAID versions
media_buy.execution.targeting - Geo targeting granularity

Error Handling

Error Code	Description	Resolution
`AUTH_REQUIRED`	Authentication needed	Provide credentials
`INTERNAL_ERROR`	Server error	Retry with backoff

Best Practices

1. Cache Capabilities Capabilities rarely change. Cache results and use last_updated for staleness detection. 2. Check Protocol Support First Before accessing protocol-specific fields, verify the protocol is in supported_protocols. 3. Check Before Requesting Don’t send postal areas for a system the seller doesn’t support. Don’t request features the seller doesn’t support. 4. Fail Fast on Incompatibility If a seller doesn’t support required capabilities, skip them early rather than discovering failures later. 5. Read the Auth Model Before Proceeding Check account.require_operator_auth immediately after discovery. Agent-trusted and operator-scoped flows diverge significantly: the former uses a single credential for all brands and operators, the latter requires per-operator credentials and sessions. 6. Use Protocol Version for Routing Route requests to appropriate API versions based on adcp.major_versions.

Next Steps

After discovering capabilities:

Set up accounts: Follow the auth model from account.require_operator_auth — see Accounts and Agents
Filter products: Use get_products with capability-aware filters
Validate properties: Fetch publisher adagents.json files for property definitions
Create buys: Use create_media_buy with supported features

Learn More

Accounts and Agents - Auth models, account setup, billing
adagents.json Specification - Publisher authorization files
Product Filters - Capability-aware filtering
Content Standards - Brand safety configuration

​Tool-Based Discovery

​Request Parameters

​Response Structure

​adcp

​supported_protocols

​account

​Auth models

​media_buy

​features

​execution

creative_specs

targeting

​conversion_tracking

​portfolio

​signals

​creative

​governance

​property_features

​extensions_supported

​The Capability Contract

​Common Scenarios

​Basic Capability Discovery

​Check multi-protocol support

​Filter sellers by capability

​Use Capabilities to Build Targeting

​Local Inventory Example (Radio, DOOH)

​Response Example

​Multi-protocol agent

​Geo Standards Reference

​Migration from list_authorized_properties (v2)

​Error Handling

​Best Practices

​Next Steps

​Learn More