Function supported_samples 

pub fn supported_samples(
    center: AnalysisCenter,
    product_type: ProductType,
    date: ProductDate,
    issue: Option<&str>,
) -> Result<&'static [&'static str], DataCatalogError>

Officially evidenced sampling tokens for one exact catalog product.

Syntax alone is not publication evidence: this query reports only cadences backed by the official product line for the selected center, family, date, and issue. Constructors enforce the same result before deriving a filename, URL, identity, or cache key.

For issue-based product lines, omitting issue selects the 0000 issue, matching default_sample_for_date. Product construction itself still requires an explicit issue.