Giving AI Agents a Deterministic Clock (Zero LLM in the Loop)

J. Servo LLC has released Sundial, an open-source tool that gives AI agents a deterministic clock for human-in-the-loop workflows, running entirely locally with zero LLM calls. Sundial tracks user absence via system-level sensors, escalates tasks through urgency tiers, and enforces an Autonomy Gate that forces agents to proceed or stand down after a hard ceiling, using empirical execution-time estimation rather than model-based guessing.

When building autonomous AI systems, developers eventually hit a fundamental architectural wall. Your coding agent asks you a question, and you step away from the keyboard. Today, nothing happens. The session hangs, the question rots, and the work stalls. At J. Servo LLC https://jservo.com , we architect enterprise AI systems to operate predictably. We built Sundial https://github.com/bigjoe-oti/sundial to act as the missing half of the human-in-the-loop framework cite: 1 . It operates on a single defining principle: Sundial measures absence, not time cite: 1 . When the human becomes the blocker, the agent's clock keeps running cite: 1 . It nudges you on your desktop, escalates politely through your absence, and greets you with continuity upon your return cite: 1 . If you never answer, the agent proceeds on its stated judgment or stands down cite: 1 . It does this deterministically, with zero model calls, and runs 100% locally cite: 1 . Relying on a Large Language Model to determine if a user has abandoned a session violates lean architecture principles. Time tracking belongs at the system level. The separation of actors is the design cite: 2 . Sundial enforces a strict architectural boundary across three main components: HIDIdleTime , lsappinfo , and pmset on macOS, and xprintidle or loginctl on Linux cite: 1 . Any missing sensor returns None and softens to wall time rather than blocking the system cite: 1 . launchd that handles presence classification and escalation cite: 1, 2 . It uses zero LLMs cite: 2 . data/ directory cite: 2 . State is written atomically using NamedTemporaryFile , fsync , and os.replace , serialized by inter-process locking via fcntl.flock cite: 1 . Escalation advances only while you genuinely have not seen the chat cite: 1 . Sundial categorizes your presence into three strict states: The system enforces urgency tiers cite: 1 . A high-urgency task utilizes a retimed ladder of 5, 10, and 20 minutes, backed by a hard 40-minute wall ceiling that forces a final resolution regardless of sensor data cite: 1 . A ripe nudge never fires mid-keystroke cite: 1 . Drawing from Interruption Science, the daemon holds ripe notifications for up to three minutes waiting for a natural typing gap or application switch before delivering cite: 1 . Sound courtesy is strictly enforced. Chimes escalate with urgency, but they mute unconditionally if your screen is locked or if you have been away for more than 30 minutes cite: 1 . Agents must stop guessing execution durations using fabricated calendar weeks cite: 1 . Sundial tracks the empirical ratio distribution of actual versus estimated time across completed tasks cite: 1 . The estimation engine lib/estimator.py operates purely mathematically to compute empirical P50 and P90 execution durations cite: 1 . It applies a small-n honesty floor, utilizing a 2.0x multiplier when sample sizes are below five, ensuring the system never provides confident numbers from thin data cite: 1, 2 . The trigger path never thinks cite: 2 . When an agent blocks on an awaiting-reply question, the ladder climbs until expiry, triggering the Autonomy Gate in lib/policy.py cite: 1 . The agent is forced into a deterministic verdict: The absolute autonomy rule: Silence-while-present is an answer, whereas silence-while-absent is a void cite: 1 . They receive distinct, deterministic responses cite: 1 . Sundial integrates via a generic hook protocol passing JSON on stdin and outputting text blocks to stdout cite: 1 . It supports ready-made adapters for claude-code , hermes , and generic environments cite: 1 . bash Clone the repository git clone https://github.com/bigjoe-oti/sundial.git https://github.com/bigjoe-oti/sundial.git ~/sundial cd ~/sundial Run the installer for your target platform ./setup.sh --name "YourName" --fresh Built with obsession by Yousef Ali and the engineering team at J. Servo LLC.