Atomic Creatives

Operations

Preview creative assets before uploading

Request

Preview creative assets before permanently uploading them. The endpoint validates files and metadata and returns the submission shape that /creative_upload would process, without creating creatives.

Creative upload limits:

Creative upload shape	Limit
Plain/non-ZIP uploaded files	500KB per uploaded file
Uploaded ZIP package	10MB per ZIP file
Direct files in the uploaded outer ZIP	500KB per direct file
Assets inside an inner HTML5 package ZIP	500KB recommended maximum; warning only
Uploaded filename form parts	10 files max

Send all files in a request with either the filename multipart field name or the legacy filename[] multipart field name; do not mix both field names in the same request. The OpenAPI x-max-file-size: 10485760 value is the transport/schema ceiling for uploaded ZIP parts. Non-ZIP 500KB and direct outer-ZIP file 500KB limits are endpoint validation rules. Assets inside an inner HTML5 package ZIP over 500KB are accepted with a meta.warnings entry unless the html5-file-too-large sub_code is promoted to an error by configuration. If multiple ZIP files are uploaded, ZIP structural/content validation preserves the legacy behavior of validating the first ZIP selected by the request.

Top-level uploads may use image extensions (.gif, .jpg, .jpeg, .png, .tiff, .tif, .svg), the legacy .swf extension, loose HTML/CSS/JS/font extensions (.html, .htm, .css, .js, .woff, .woff2, .ttf, .otf), or ZIP packages. ZIP-inner HTML5 assets may use image extensions plus .html, .htm, .css, .js, .woff, .woff2, .ttf, .otf, .mp4, and .webm.

HTML5 packages must use a two-level ZIP structure: the outer ZIP contains one or more inner ZIP files, each inner ZIP contains the HTML5 creative assets, and backup images are included in the outer ZIP. Loose files must not be uploaded alongside an HTML5 ZIP package. Nested ZIPs beyond two levels are rejected.

HTML5 validation errors and warnings use these stable sub_code values:

`sub_code`	Default disposition	Scope	Trigger
`html5-missing-click-tracker`	Error	Inner package	No HTML/JS file contains a MediaMath click-tracker macro
`html5-noscript-tag`	Warning	Inner package	Root HTML contains a `<noscript>` tag
`html5-storage-api`	Warning	Inner package	HTML/JS file uses `localStorage` or `sessionStorage`
`html5-external-reference`	Warning	Inner package	Root HTML references an external asset
`html5-invalid-filename-chars`	Warning	Inner package	File name contains spaces, non-ASCII, or other non-standard characters
`html5-missing-file-extension`	Warning	Inner package	Extensionless file is recognized by content signature or root HTML reference
`html5-unsafe-filename-path`	Error	Inner package	File path is absolute, contains `.`/`..`, drive-letter, or UNC path components
`html5-filename-too-long`	Error	Inner package	File path exceeds 255 characters
`html5-unsupported-file-type`	Error	Outer ZIP and inner package	File extension is not allowed
`html5-file-too-large`	Warning	Inner package	Inner package asset exceeds the recommended 500KB maximum
`html5-file-too-large`	Error	Outer ZIP direct entry	Direct entry in uploaded outer ZIP exceeds 500KB
`html5-file-read-error`	Error	Inner package	Extracted HTML/JS file cannot be read
`html5-backup-mismatch`	Warning	HTML5 package auto-discovery	Backup image matches the package name only by letter case
`html5-backup-mismatch`	Error	HTML5 package auto-discovery	No backup metadata and no matching backup image exists
`html5-backup-mismatch`	Error	HTML5 package manual backup	Specified backup file is absent from the ZIP
`html5-invalid-package-structure`	Error	Outer ZIP	HTML appears directly in the outer ZIP
`html5-nested-zip-too-deep`	Error	Outer ZIP	ZIP nesting exceeds two levels
`html5-separate-files`	Error	Multipart request	Loose files are uploaded alongside an HTML5 ZIP package
`html5-submission-name-mismatch`	Error	Outer ZIP (HTML5)	Inner ZIP name is missing from `metadata.submissions[].name`
`submission-name-mismatch`	Error	Outer ZIP (non-HTML5)	Plain ZIP file is missing from `metadata.submissions[].name`
`zip-too-large`	Error	Uploaded ZIP	Uploaded ZIP exceeds 10MB
`html5-validation-error`	Error	Fallback	Internal fallback for an unmapped HTML5 validation rule

Security

Auth0(Required scopes: offline_accessmanage:services)

Bodymultipart/form-datarequired

filenameArray of strings, (binary), [ 1 .. 10 ] items(creative_upload_filename)required

Creative files to upload. Send all files in a request as either filename or the legacy filename[] field name; do not mix both field names in the same request.

Loose/non-ZIP uploads are limited to 500KB per file. Uploaded ZIP packages are limited to 10MB per ZIP. Direct files in the uploaded outer ZIP are limited to 500KB. Assets inside an inner HTML5 package ZIP over 500KB are accepted with a warning unless the html5-file-too-large sub_code is promoted to an error. If multiple ZIP files are uploaded, ZIP structural/content validation preserves the legacy behavior of validating the first ZIP selected by the request.

metadataobject(creative_upload_metadata_draft)required

JSON metadata for the preview request. submissions is optional for draft: when omitted, the API attempts to infer submission entries from the uploaded files.

curl -i -X POST \
  https://api.mediamath.com/api/v3.0/creative_draft \
  -H 'Authorization: Bearer <YOUR_TOKEN_HERE>' \
  -H 'Content-Type: multipart/form-data' \
  -F filename=@banner_300x250.jpg \
  -F 'metadata="{\"advertiser_id\":100212,\"is_https\":true,\"submissions\":[{\"name\":\"banner_300x250.jpg\",\"click_through_url\":\"https://example.com/click\",\"landing_page\":\"https://example.com/landing\",\"concept_id\":4157184}]}";type=application/json'

Responses

Preview generated successfully

Bodyapplication/json

dataobject(creative_draft_response_data)

metaobject(creative_single_metadata_with_warnings)

Response

{
  "data": {
    "uploaded_files": [ … ],
    "metadata": { … }
  },
  "meta": {
    "status": "success"
  }
}