Everything you need. Nothing you don't.
01Drop-in create() / async_create() — replaces client.messages.create(...) one-for-one.
02Best-effort usage logging — writes one SQLite row per call, NEVER raises into your code.
03₹-cost intelligence — per source × model × token-type, priced from a bundled rates file.
04Cache savings tracking — ₹ actually saved by cache reads + ₹ missed by eligible-but-uncached calls.
05Cost-report CLI — PER-MODEL, SAVED-BY-CACHE, MISSED-SAVINGS, and TOTAL sections (1h / 24h / 1w / 1m windows).
06Model-lock gate (opt-in) — lock haiku / sonnet / opus families; off by default, no surprises.
07Nothing hardcoded (R13) — db, rates, lockfile, home all config / env-driven; edit the rates yaml, not code.