This is the deepest feature in the product and deserves the most careful
user-facing writeup. Must cover, in plain language:
- What a tag rule is and how it maps a dimension value (service, account,
usage type, region) to a
team/custom tag — no source-infra tags required.
- Split rules: one rule can divide matched spend across multiple tag
values by weight, for genuinely shared cost (e.g. a shared cluster).
- Proportional redistribution: dissolving an “Untagged” bucket into the
others in proportion to their already-tagged spend.
- The one thing users will trip on: redistribution/splits are computed
per day, not per chart bucket — so don’t be surprised if an hourly
view shows redistributed money landing in different hours than you’d
expect intuitively; it’s spread across a day’s hours by that team’s own
usage profile.
- Reassure: totals always reconcile — the sum across all tag values equals
the total for that scope, always.
Use a worked example (e.g. splitting a shared observability bill 60/40
across two teams) rather than describing the mechanism abstractly.
