Creative Manifests

Creative manifests are structured specifications that define all the assets and metadata needed to render a creative in a specific format. They pair the requirements defined by Creative Formats with actual asset content. For an overview of how formats, manifests, and creative agents work together, see the Creative Protocol Overview.

Manifest Structure

Basic Structure

{
  format_id: {                 // Format this manifest is for
    agent_url: string;         // Creative agent URL
    id: string;                // Format identifier
  };
  promoted_offering?: string;  // Product being advertised (maps to create_media_buy)
  assets: {
    [asset_id: string]: {      // Keyed by asset_id from format's assets_required
      // Asset type is determined by format specification, not declared here
      // Type-specific fields depend on asset_type defined in format's assets_required

      // Image: url, width, height, format, alt_text
      // Video: url, width, height, duration_ms, format, bitrate_kbps
      // Audio: url, duration_ms, format, bitrate_kbps
      // Text: content, language
      // URL: url, description
      // HTML: content or url, version
      // CSS: content, media
      // JavaScript: content, module_type
      // VAST: url or content, vast_version, vpaid_enabled, duration_ms, tracking_events
      // DAAST: url or content, daast_version, duration_ms, tracking_events, companion_ads
      // Promoted Offerings: brand_manifest, product_selectors, offerings, asset_selectors
      // Webhook: url, method, timeout_ms, response_type, security, supported_macros, required_macros
    }
  };
}

Asset IDs

Each asset in a manifest is keyed by its asset_id, which must match an asset_id defined in the format’s assets_required array. The asset ID serves as the technical identifier for referencing the asset requirement in the format specification. How Asset IDs Work: When a format defines required assets:

{
  "assets_required": [
    {
      "asset_id": "banner_image",
      "asset_type": "image",
      "required": true
    },
    {
      "asset_id": "clickthrough_url",
      "asset_type": "url",
      "required": true
    }
  ]
}

Your manifest must use those exact asset IDs as keys:

{
  "assets": {
    "banner_image": {        // ← Matches asset_id from format
      "asset_type": "image",
      "url": "https://cdn.example.com/banner.jpg",
      "width": 300,
      "height": 250
    },
    "clickthrough_url": {    // ← Matches asset_id from format
      "asset_type": "url",
      "url": "https://example.com/landing"
    }
  }
}

Common Asset IDs (vary by format):

banner_image, hero_image: Primary visual assets
logo: Brand logo
headline, description: Text content
cta_text: Call-to-action button text
video_file: Video content
vast_tag: VAST XML for video delivery
clickthrough_url: Landing page URL

Always check the specific format’s assets_required to see which asset IDs are required.

Complete Example

Here’s a complete creative manifest showing the current structure without redundant fields:

{
  "format_id": {
    "agent_url": "https://creative.adcontextprotocol.org",
    "id": "display_300x250"
  },
  "promoted_offering": "Premium Dog Food",
  "assets": {
    "banner_image": {
      "url": "https://cdn.example.com/banner.jpg",
      "width": 300,
      "height": 250,
      "format": "jpg"
    },
    "headline": {
      "content": "Nutrition Dogs Love",
      "language": "en"
    },
    "description": {
      "content": "Made with real chicken and wholesome grains",
      "language": "en"
    },
    "clickthrough_url": {
      "url": "https://example.com/products/premium-dog-food",
      "description": "Product landing page"
    }
  }
}

Note: Asset types (image, text, url) are not declared in the manifest. They are determined by looking up each asset_id in the format specification’s assets_required array. The format tells us that banner_image should be type image, headline should be type text, etc.

Types of Creative Manifests

Creative manifests can be static, dynamic, or hybrid - reflecting the three creative agent modalities above.

Static Manifests

Static manifests contain all assets ready for immediate rendering. These are produced by creative agents in Static Asset Delivery or Prompt to Static Rendering modes.

{
  "format_id": {
    "agent_url": "https://creative.adcontextprotocol.org",
    "id": "native_responsive"
  },
  "assets": {
    "hero_image": {              // asset_id from format spec
      "asset_type": "image",
      "url": "https://cdn.example.com/hero.jpg",
      "width": 1200,
      "height": 627,
      "format": "jpg",
      "alt": "Product image"
    },
    "logo": {                    // asset_id from format spec
      "asset_type": "image",
      "url": "https://cdn.example.com/logo.png",
      "width": 100,
      "height": 100,
      "format": "png"
    },
    "headline": {                // asset_id from format spec
      "asset_type": "text",
      "content": "Premium Quality You Can Trust"
    },
    "description": {             // asset_id from format spec
      "asset_type": "text",
      "content": "Discover why veterinarians recommend our formula"
    },
    "cta_text": {                // asset_id from format spec
      "asset_type": "text",
      "content": "Learn More"
    }
  }
}

Use Cases:

Traditional display advertising
Pre-rendered video ads
Static native ads
Fixed creative campaigns

Dynamic Manifests

Dynamic manifests include endpoints or code for real-time generation. These are produced by creative agents in Prompt to Dynamic Rendering mode (DCO/Generative).

{
  "format_id": {
    "agent_url": "https://creative.adcontextprotocol.org",
    "id": "display_dynamic_300x250"
  },
  "assets": {
    "dynamic_content": {
      "asset_type": "webhook",
      "url": "https://creative-agent.example.com/render/campaign-123",
      "method": "POST",
      "timeout_ms": 500,
      "supported_macros": ["WEATHER", "TIME", "DEVICE_TYPE", "COUNTRY"],
      "response_type": "html",
      "security": {
        "method": "hmac_sha256",
        "hmac_header": "X-Signature"
      },
      "fallback_required": true
    },
    "fallback_image": {
      "asset_type": "image",
      "url": "https://cdn.example.com/fallback-300x250.jpg",
      "width": 300,
      "height": 250,
      "format": "jpg"
    }
  }
}

Use Cases:

Weather-based creative
Time-of-day personalization
Product availability messaging
Real-time inventory updates

Note: For client-side dynamic rendering, use html or javascript asset types with embedded tags instead of webhooks. Dynamic manifests can mix asset types - some assets may be static (images, videos) while others are dynamic (webhooks, tags with macros). For example, a video VAST tag with a static hero video but a personalized end card webhook.

DOOH Manifests with Impression Tracking

Digital Out-of-Home (DOOH) creatives use impression tracking just like other formats, but with venue-specific macros instead of device identifiers.

{
  "format_id": {
    "agent_url": "https://creative.adcontextprotocol.org",
    "id": "dooh_billboard_1920x1080"
  },
  "promoted_offering": "Premium Coffee Blend",
  "assets": {
    "billboard_image": {
      "asset_type": "image",
      "url": "https://cdn.example.com/billboard-1920x1080.jpg",
      "width": 1920,
      "height": 1080,
      "format": "jpg"
    },
    "impression_tracker": {
      "asset_type": "url",
      "url_type": "tracker",
      "url": "https://tracking.example.com/imp?screen={SCREEN_ID}&venue={VENUE_TYPE}&ts={PLAY_TIMESTAMP}&lat={VENUE_LAT}&lon={VENUE_LONG}"
    }
  }
}

DOOH-Specific Macros (see Universal Macros for complete list):

{SCREEN_ID} - Unique identifier for the physical screen
{VENUE_TYPE} - Venue category (airport, mall, transit, highway, retail)
{VENUE_LAT} / {VENUE_LONG} - Physical location coordinates
{PLAY_TIMESTAMP} - When creative displayed (Unix timestamp)
{DWELL_TIME} - Average viewer dwell time at this location

The mechanics are identical to digital impression tracking - a URL fires when the ad displays. The difference is DOOH uses fixed venue context instead of dynamic device identifiers.

Working with Manifests

Creating Manifests

Manifests are JSON structures that can be created in two ways: 1. Manual Assembly Construct manifests directly by pairing format requirements with your assets:

{
  "format_id": {
    "agent_url": "https://creative.adcontextprotocol.org",
    "id": "native_responsive"
  },
  "promoted_offering": "Premium Salmon Formula",
  "assets": {
    "hero_image": {
      "asset_type": "image",
      "url": "https://cdn.example.com/salmon-hero.jpg",
      "width": 1200,
      "height": 627
    },
    "headline": {
      "asset_type": "text",
      "content": "New Premium Salmon Formula"
    }
  }
}

2. AI-Generated (Optional) Use build_creative to have a creative agent generate manifests from natural language briefs. See Generative Creative for details.

Validating Manifests

Before using a manifest, validate it against format requirements:

Format Compatibility: Ensure format_id matches intended format
Required Assets: All required asset_id values from the format are present as keys in the manifest’s assets object
Asset Key Matching: Each key in the manifest’s assets object MUST match an asset_id from the format’s assets_required array
Asset Specifications: Each asset meets format requirements (dimensions, file size, duration, etc.)
Macro Support: Dynamic manifests properly handle required macros

What happens with invalid asset keys?

Missing required asset_id: Creative agents MUST reject the manifest with an error listing which required assets are missing
Unknown asset_id: Creative agents MUST reject manifests containing asset keys that don’t match any asset_id in the format. This catches typos and incompatible formats immediately.
Wrong asset_type: If an asset doesn’t match the type requirement for that asset_id in the format specification, reject with a clear type mismatch error

Creative agents that implement build_creative handle validation automatically. For manually constructed manifests, validate against the format specification returned by list_creative_formats. Format-Aware Validation: Creative manifest validation MUST be performed in the context of the format specification. The format defines what type each asset_id should be, eliminating any validation ambiguity. Asset type information is NOT included in the manifest itself - it’s determined by looking up the asset_id in the format’s assets_required array.

Validation Flow

When a creative agent receives a manifest for validation:

Extract format_id from the manifest
Fetch format specification from the format registry (local or remote based on agent_url)
For each asset key in manifest.assets:
- Look up the asset_id in format.assets_required
- If not found → reject with error “Unknown asset_id ‘banner_imag’ not defined in format”
- If found → determine the expected asset_type from the format requirement
- Fetch the asset type schema (e.g., /schemas/v1/core/assets/image-asset.json)
- Validate the asset payload against that schema
- Validate the asset meets any additional constraints in the format’s requirements field
Check all required assets are present (where required: true in format spec)
Validate type-specific constraints (dimensions, file size, duration, etc.)

The format specification is the single source of truth for what type each asset_id should be and what constraints apply. Validation is runtime, not schema-time: The JSON schema for creative manifests uses a flexible pattern (^[a-z0-9_]+$) for asset keys because the valid keys depend on which format you’re using. Validation against the specific format’s assets_required happens when you submit the manifest to a creative agent.

Previewing Manifests

Use the preview_creative task to see how a manifest will render:

{
  "format_id": {
    "agent_url": "https://creative.adcontextprotocol.org",
    "id": "native_responsive"
  },
  "creative_manifest": {
    "format_id": {
      "agent_url": "https://creative.adcontextprotocol.org",
      "id": "native_responsive"
    },
    "assets": {
      "hero_image": {
        "url": "https://cdn.example.com/hero.jpg",
        "width": 1200,
        "height": 627
      },
      // ... other assets
    }
  },
  "macro_values": {
    "CLICK_URL": "https://example.com/landing",
    "CACHE_BUSTER": "12345"
  }
}

The creative agent returns preview URLs and renderings.

Submitting Manifests

Manifests are submitted to the creative library using sync_creatives, then referenced by ID in media buys:

{
  "task": "sync_creatives",
  "parameters": {
    "creatives": [
      {
        "creative_id": "native-salmon-v1",
        "name": "Salmon Special Native Ad",
        "format_id": {
          "agent_url": "https://creative.adcontextprotocol.org",
          "id": "native_responsive"
        },
        "manifest": {
          "format_id": {
            "agent_url": "https://creative.adcontextprotocol.org",
            "id": "native_responsive"
          },
          "promoted_offering": "Fresh Pacific Salmon",
          "assets": {
            "headline": {
              "asset_type": "text",
              "content": "Fresh Pacific Salmon - 20% Off Today"
            },
            "main_image": {
              "asset_type": "image",
              "url": "https://cdn.example.com/salmon.jpg",
              "width": 1200,
              "height": 628
            }
          }
        }
      }
    ]
  }
}

Then reference in media buys by creative_id. Each manifest is for a single format.

Macro Substitution in Manifests

Manifests support macro placeholders for dynamic values. AdCP uses universal macros that work consistently across all publishers. See Universal Macros for complete documentation on available macros, macro substitution process, and format-specific macro support.

Best Practices

For Creative Agents

Complete Manifests: Include all required assets for the format
Validate Assets: Ensure assets meet format specifications
Provide Fallbacks: Include fallback assets for dynamic creatives
Document Macros: Clearly specify which macros are used
Version Assets: Use versioned URLs for asset management

For Publishers

Validate on Receipt: Check manifests against format requirements
Cache Assets: Pre-fetch and cache hosted assets
Handle Failures: Implement fallback rendering for dynamic manifests
Support Macros: Implement full Universal Macro support
Provide Templates: Offer rendering templates for custom formats

For Buyers

Validate Manifests: Ensure manifests match format requirements (manually or via build_creative)
Preview First: Always preview manifests before submission
Test Macros: Verify macro substitution works as expected
Optimize Assets: Ensure assets are properly sized and compressed
Organize Libraries: Use creative libraries for asset management

Advanced Topics

Repeatable Asset Groups

For carousel, slideshow, and multi-asset formats, see the Carousel & Multi-Asset Formats guide for complete documentation on repeatable asset groups.

Schema Reference

Creative Formats - Understanding format specifications and discovery
Channel Guides - Format examples across video, display, audio, DOOH, and carousels
build_creative Task
preview_creative Task

Getting Started

Protocols

Signals Protocol

Curation Protocol

Media Buy Protocol

Creative

Reference

Creative Manifests

Creative Manifests

Manifest Structure

Basic Structure

Asset IDs

Complete Example

Types of Creative Manifests

Static Manifests

Dynamic Manifests

DOOH Manifests with Impression Tracking

Working with Manifests

Creating Manifests

Validating Manifests

Validation Flow

Previewing Manifests

Submitting Manifests

Macro Substitution in Manifests

Best Practices

For Creative Agents

For Publishers

For Buyers

Advanced Topics

Repeatable Asset Groups

Schema Reference

Getting Started

Protocols

Signals Protocol

Curation Protocol

Media Buy Protocol

Creative

Reference

​Creative Manifests

​Manifest Structure

​Basic Structure

​Asset IDs

​Complete Example

​Types of Creative Manifests

​Static Manifests

​Dynamic Manifests

​DOOH Manifests with Impression Tracking

​Working with Manifests

​Creating Manifests

​Validating Manifests

​Validation Flow

​Previewing Manifests

​Submitting Manifests

​Macro Substitution in Manifests

​Best Practices

​For Creative Agents

​For Publishers

​For Buyers

​Advanced Topics

​Repeatable Asset Groups

​Schema Reference

​Related Documentation

Creative Manifests

Manifest Structure

Basic Structure

Asset IDs

Complete Example

Types of Creative Manifests

Static Manifests

Dynamic Manifests

DOOH Manifests with Impression Tracking

Working with Manifests

Creating Manifests

Validating Manifests

Validation Flow

Previewing Manifests

Submitting Manifests

Macro Substitution in Manifests

Best Practices

For Creative Agents

For Publishers

For Buyers

Advanced Topics

Repeatable Asset Groups

Schema Reference

Related Documentation