cost — Cowork → Claude API cost estimator

Overview

Claude Cowork (and Claude Code) already run on the Claude API and write one JSONL transcript per conversation under ~/.claude/projects/. Every assistant turn records the actual API call it made, including the prompt-cache breakdown. This skill reads those transcripts, sums the real token usage, and prices it at Anthropic list rates (cache-aware) so a business user can judge what their conversations would cost on the API instead of the subscription.

It answers three things:

1. Token count (current conversation and/or per conversation across history).
2. Exact tokens needed to replay the same multi-turn, tool-using conversation on the API.
3. Cost of those tokens in USD and EUR, accounting for prompt-cache hits.

When to Use This Skill