In Claude Code, src/hooks/caveman-mode-tracker.js resolves src/hooks/caveman-stats.js next to itself and runs it on /caveman-stats. The hook does not block the prompt: it supplies the report through hookSpecificOutput.additionalContext with an instruction to print it verbatim inside a fenced code block. Do exactly that, and do not calculate, recompute or re-round the numbers yourself.
In Gemini CLI, direct the user to /stats model for current session token usage or /stats session for session statistics. Gemini custom commands are prompts; they cannot invoke the built-in command or read its live session metrics. Never read Claude Code transcripts as Gemini usage. In other hosts, use a native usage report if one is available; otherwise say that current session usage is unavailable. The Claude reader and its lifetime history apply only to Claude Code. Savings remain unknown in every host without a measured comparison.
The report shows recorded output and cache-read tokens, response counts, and mode attribution where available. Savings are unknown: the transcript has no measured comparison without Caveman. Do not infer saved tokens, percentages, dollars, rule overhead, or a net result from output counts or the current mode.
--all and --since 7d aggregate the latest recorded output count per session. --share reports observed usage with savings unknown. Historical est_saved_* fields are ignored; their original history rows remain on disk. The statusline shows the active mode without the retired savings badge.
Original/current memory-file pairs are reported by their measured byte sizes. Those file-size differences do not establish provider token or billing savings. See docs/HONEST-NUMBERS.md.