Vellum Heartbeat

The heartbeat feature runs your HEARTBEAT.md checklist periodically in a background conversation. Each run, the assistant works through the checklist and flags anything that needs attention.

Setup

Edit config.json using file_edit:

1. Enable heartbeat: Set heartbeat.enabled to true.
2. Set interval: Set heartbeat.intervalMs (milliseconds between runs, default: 3600000 = 1 hour).
3. Optional active hours: Set heartbeat.activeHoursStart and heartbeat.activeHoursEnd (0-23) to restrict runs to certain hours. Both must be set together.

Example config.json heartbeat section:

{
  "heartbeat": {
    "enabled": true,
    "intervalMs": 1800000,
    "activeHoursStart": 8,
    "activeHoursEnd": 22
  }
}

Then edit HEARTBEAT.md with the checklist items. The assistant will work through this file each heartbeat run.

Notes

• Toggling heartbeat.enabled requires an assistant restart to take effect.
• Changes to HEARTBEAT.md take effect on the next heartbeat run (no restart needed).
• The heartbeat runs in a separate background conversation, not the user's active chat.

Inference

Heartbeat runs use the heartbeatAgent call site, which by default resolves to the cost-optimized profile so background checks stay cheap. Override via llm.callSites.heartbeatAgent in workspace config (profile, provider, model, effort, thinking — whatever the profile supports).