ai-conversation-impact/tasks/05-calibrate-tokens.md
claude 0543a43816 Initial commit: AI conversation impact methodology and toolkit
CC0-licensed methodology for estimating the environmental and social
costs of AI conversations (20+ categories), plus a reusable toolkit
for automated impact tracking in Claude Code sessions.
2026-03-16 09:46:49 +00:00

1.2 KiB

Task 5: Calibrate token estimates

Plan: reusable-impact-tooling Status: DONE (hook now extracts actual token counts from transcript usage fields; falls back to heuristic; weights cache reads at 10% for energy estimates) Deliverable: Updated estimation logic in pre-compact-snapshot.sh

What to do

  1. The current heuristic uses 4 bytes per token. Claude's tokenizer (based on BPE) averages ~3.5-4.5 bytes per token for English prose but varies for code, JSON, and non-English text. The transcript is mostly JSON with embedded code and English text.

  2. Estimate a better ratio by:

    • Sampling a known transcript and comparing byte count to the token count reported in API responses (if available in the transcript).
    • If API token counts are present in the transcript JSON, use them directly instead of estimating.
  3. The output token ratio (currently fixed at 5% of transcript) is also rough. Check if the transcript contains usage fields with actual output token counts.

  4. Update the script with improved heuristics or direct extraction.

Done when

  • Token estimates are within ~20% of actual (if verifiable) or use actual counts from the transcript when available.