What each log line should tell you
A useful entry names the app (Document Studio, PDF Intelligence, Design Studio), the tool (rewrite, summarise, logo generation, and so on), the model, token counts, duration, and outcome. That is enough to attribute usage without reading prompt contents in a finance meeting.
Outcome matters because failed calls use zero tokens. If a run errors, the trail should still exist for debugging and support — but it should not punish the wallet. Success lines carry the consumption that shared usage meters.
Aggregations by studio and tool help admins set norms. If image generation dominates a month, maybe the team needs stronger creative briefs. If full-document generate dominates, maybe narrower rewrite tools would suffice.
Export the story when finance needs reconciliation. A month reconstructed from the ledger beats a month reconstructed from memory and screenshots.