Prompt-Caching on Tokenise

A model switch re-reads your whole session uncached. Put a price on it with a PreModelSwitch hook

Wed, 28 Oct 2026 16:04:00 +0000

A session is 180,000 tokens deep, the cache is warm, and someone types /model opus because the next step looks hard. Nothing on screen says what that costs. The next request reads the entire conversation again with no cache hits, on a model that has never seen it.

Claude Code now compacts your idle session before the cache expires. Here's when that saves money and when it costs you

Fri, 16 Oct 2026 11:03:00 +0000

You step away from a long Claude Code session for lunch. An hour and a bit later you type a one-line follow-up, and that single message reprocesses the whole conversation from scratch, because the one-hour prompt cache lapsed while you were gone. At 400,000 tokens of context on Sonnet 5.5, that one line costs about $1.60 before the model has said anything.

Sonnet 5.5 cache reads just halved, but idle gaps still decide your bill

Mon, 12 Oct 2026 16:03:00 +0000

Sonnet 5.5 prompt-cache reads now cost $0.10 per million tokens, half the $0.20 they cost before. Anthropic’s API release notes date the cut to 7 October 2026, and say cache writes and every other price stayed where they were. Claude Code 2.1.296 picked up the new figure in its cost display.