Bug type

Regression (worked before, now fails)

Summary

Every time a cron job runs, it creates a new isolated session that is never cleaned up. Over time, sessions.json grows to 1000+ entries, causing massive token waste and memory issues.

Steps to reproduce

1. Create a cron job with default settings
2. Let it run for a few hours
3. Check ~/.openclaw/agents/main/sessions/sessions.json

Expected behavior

Cron jobs should either reuse the main session (sessionTarget: "main") or clean up isolated sessions after execution.

Actual behavior

Each cron execution creates a new isolated session that is never deleted. sessions.json grows to 1000+ entries, causing memory issues, slow loading, and massive token waste (each session consumes ~16k tokens).

OpenClaw version

latest

Operating system

macOS

Install method

No response

Logs, screenshots, and evidence

Impact and severity

Affected: All users with cron jobs enabled
Severity: High (massive token waste, memory issues)
Frequency: 100%
Consequence: Each cron run wastes ~16k tokens, sessions.jsonbloats to 1000+ entries

Additional information

No response