Claude Code keeps your chat cached for about an hour. Come back after it expires and your next message reloads everything at full price. Tokra is a small tray app that shows the countdown and warns you before it goes cold.
What it would look like
Cache warm · 47 min left · context 82k
⚠ 5 min left. If you step away now, your next message reloads 82k tokens at full price. Send something now, or save a handoff and start fresh later.
Why: I measured it
Question in a fresh chat
$0.038
Same question, long chat (~65k), no break
$0.007–0.015
Same question, same chat, after a 1h+ break
$0.157
Next message after that
$0.007
Pro plan, Sonnet, 3 runs each, from Claude Code's own JSON cost output. Full write-up on r/ClaudeAI.
Planned features
Cache countdown in the Windows tray, per session
Warning a few minutes before the cache expires
Shows how big the next cold reload would be
One-click handoff summary so you can /clear and resume cheaply
Runs locally. Reads Claude Code's own status data, sends nothing anywhere