VASTlint
DAAST-1.0-mediafile-type

DAAST-1.0-mediafile-type

DAAST `<MediaFile>` must have a type attribute

ErrorDAASTIAB DAAST 1.0 §3.2.2DAAST 1.0 and 1.1 (all DAAST documents)

Short answer

The type attribute on a DAAST <MediaFile> carries the MIME type of the audio asset (e.g., audio/mpeg). Players use it to determine codec support before fetching the file.

Why this matters in production

This rule is usually a delivery blocker. Many players, SDKs, and ad servers will discard the response or skip the affected creative once this condition is hit. DAAST rules validate the structural and semantic requirements specific to digital audio ad serving. Audio-specific fields like Category, AdInteractions, and audio MediaFile attributes are required by the spec and are absent from standard VAST validation. Affected scope: DAAST 1.0 and 1.1 (all DAAST documents).

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