SleepTool

• Entity ID: ent-sleep-tool
• Type: tool
• Scope: shared

What it is

SleepTool is a specialized tool available only in KAIROS proactive mode that lets the autonomous agent yield control explicitly — choosing when to go dormant and for how long. It replaces the naive approach of running a tick on every event loop cycle with agent-directed scheduling.

Why it exists

In KAIROS's always-on tick loop, every tick without useful work is a wasted API call. The agent needs a way to say "nothing to do right now, wake me in 5 minutes" without the system burning tokens on empty ticks. SleepTool solves this by making sleep a first-class tool call with an explicit cost trade-off.

The tool description surfaces the economics directly to the model: "Each wake-up costs an API call, but the prompt cache expires after 5 minutes of inactivity — balance accordingly." The agent decides its own rhythm: how long to sleep, when to wake early for a slow process, when to stay awake during active monitoring.

What depends on it

• KAIROS — SleepTool is only available when proactive mode is active, not a general feature
• Cost optimization — without SleepTool, KAIROS would burn API calls on every tick, making autonomous operation prohibitively expensive
• Cache economics — the 5-minute cache expiry creates a natural tension: sleep too long and lose the cache, sleep too little and waste API calls

Trade-offs and limitations

• Only available in proactive mode — not accessible to regular Claude Code sessions
• The 5-minute cache expiry window creates a hard constraint on maximum sleep duration for cache-sensitive operations
• The agent must learn the right sleep/wake cadence for each task profile — too aggressive wastes tokens, too passive misses events

Key claims

• SleepTool is the only tool in Claude Code that is conditionally available based on operating mode
• The tool description explicitly encodes the cost/benefit trade-off for the model to reason about

Relationships

• depends_on: kairos
• related_to: cache-economics, prompt-cache
• used_by: autonomous agents, background monitoring tasks

Evidence

• src-20260409-a14e9e98c3cd: Internals — KAIROS section