Cold starts come in different forms
A new user has no individual history. A new item has no interaction history. A small platform may have sparse data across both. These are related problems, but they need different inputs and fallback strategies.
Let the catalog contribute
Titles, categories, attributes, and content representations can help establish similarity before an item gathers interactions. Consistent item identifiers and useful metadata make that approach easier to evaluate.
Use context with care
Session actions may reveal immediate intent even when a person is anonymous. Use only the signals appropriate for your product and data practices. A missing history should lead to a sensible fallback rather than an empty experience.
Measure beyond the average
Compare new and returning visitors separately. Look at item coverage and the visibility of new catalog entries. Whether a strategy helps depends on catalog quality, interaction volume, and the implementation.