v132 · miscellaneous

Attribution Reporting API Feature (Aggregatable Named Budgets)

We are landing the following change to the Attribution Reporting API focused on: * making it easier to predefine contribution budget allocation for aggregate reports

concepts

  1. Named Budgets

    Attribution Reporting lets sources declare named contribution budgets. Different verticals on the same site can split the aggregation budget cleanly.

  2. trigger registration

    The trigger side: build the JSON, pick which bucket to draw from, watch the over-budget rejection.

  3. budget strategy lab

    Equal split, traffic-weighted, hero-category — run simulated traffic for 60s against each and see which strategy wastes headroom vs. starves a vertical.

  4. report anatomy

    Watch the named_budget field flow from trigger JSON to histogram contribution to encrypted aggregatable report, with a flattened view of every relevant report field.

why it shipped

This change is based on API caller feedback and the need for more control over the contribution budget allocation.

references