Heartbeat Service

The autonomous background loop that drives task execution and self-correction.

Overview

The HeartbeatService is Tars’ background maintenance engine. It runs on a configurable interval (default: 300 seconds) and manages memory synchronization, filesystem cleanup, and self-correcting health checks.

Note: For precisely timed scheduled tasks (cron), Tars uses a separate Cron Service that polls every 60 seconds.

The Tick Loop

Each heartbeat tick follows this sequence:

1. Cleanup — AttachmentProcessor.cleanup() removes old temp files (1h) and uploads (24h).
2. Memory Sync — MemoryManager.fullSync() re-indexes the brain (facts, skills, and past sessions).
3. Autonomous Check — Performs a SILENT_ACK heuristic check to see if autonomous action is required.

tick()
 ├── cleanup()           # Remove stale files
 ├── fullSync()          # Rate-limited re-indexing
 └── autonomousCheck()   # Heuristic goal assessment

The SILENT_ACK Protocol

When no scheduled tasks are due, the heartbeat sends a special prompt to the AI to verify the system’s state.

This interaction happens in an Ephemeral Session. It does not use the user’s active conversation ID, which means background autonomous checks never bloat your main context window or interfere with your chat history.

Two outcomes:

• SILENT_ACK response — Everything is fine. The ephemeral session is discarded.
• Any other response — The AI detected something that needs attention. The action is logged and the Supervisor handles the resulting tool calls or notifications.

This creates a self-correcting feedback loop where the AI periodically reviews its own state and takes initiative when needed.

Concurrency Guard

A boolean isExecuting flag prevents overlapping ticks. If a tick is still running when the next interval fires, it’s skipped.

Configuration

Adjust via tars setup or edit ~/.tars/config.json directly.