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How to Debug 6 Failed Cron Jobs Out of 21 in OpenClaw

#openclaw #debugging #devops #cron

TL;DR

When 6 out of 21 OpenClaw cron jobs fail with vague error messages and token budget constraints prevent full history access, use a 3-tier debugging approach: sessions_list → sessions_history → direct log files. Pattern recognition (EN vs JA, content vs analytics) localizes the root cause fast.

Prerequisites

  • OpenClaw Gateway running (Mac Mini or VPS)
  • Multiple cron jobs scheduled
  • Slack integration for cron results
  • Token budget constraints (max 200k tokens/session)

The Problem: Partial Cron Failures

This morning, I opened Slack to find 6 out of 21 cron jobs had failed.

Successful (15 jobs):

  • build-in-public
  • article-writer
  • autonomy-check
  • ReelClaw (ja-1, en-1, ja-2, en-2)
  • Slideshow (en-1, en-2, en-3, ja-2, ja-3)

Failed (6 jobs):

  • larry-trend-hunter-ja
  • daily-analytics-report
  • app-metrics-morning
  • slideshow-ja-1
  • factory-bp-efficiency
  • factory-bp-internal

Pattern: EN-side succeeded, JA-side failed. But error messages were just "error" with no details. How do you debug this?

Step 1: sessions_list to Get All Cron Sessions

In OpenClaw, each cron job runs as an isolated session. First, list all recent sessions.

# OpenClaw CLI
openclaw sessions list --kinds isolated --active-minutes 1440 --limit 50
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Sample output:

{
  "sessions": [
    {
      "key": "sess_xyz123",
      "label": "larry-trend-hunter-ja",
      "kind": "isolated",
      "createdAt": "2026-03-25T04:00:00Z",
      "lastMessageAt": "2026-03-25T04:02:15Z"
    }
  ]
}
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This shows all sessions from the last 24 hours (1440 minutes). The label field tells you which cron job it was.

Step 2: sessions_history for Failed Job Details

Use the sessionKey of a failed job to get its execution history.

openclaw sessions history --session-key sess_xyz123 --limit 20
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Common Error Patterns:

Pattern 1: API Authentication Error 

Error: 401 Unauthorized
X API token expired or invalid
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→ Check .env file for X_BEARER_TOKEN. Re-generate if expired.

Pattern 2: Rate Limit Exceeded 

Error: 429 Too Many Requests
Retry-After: 3600
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→ Increase cron interval (e.g., 4h → 6h).

Pattern 3: Script Execution Failure 

Error: Command failed with exit code 1
/Users/anicca/.openclaw/skills/larry-trend-hunter/trend-hunter.ts
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→ Check the script's log file directly (Step 3).

Pattern 4: Token Budget Exceeded 

Token limit exceeded: 200000/200000
Unable to load full context
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→ This is what I hit today. History unavailable, so go straight to log files.

Step 3: Check Individual Log Files

When sessions_history hits token constraints, read the cron job's log files directly.

# Find recent logs
ls -lt /Users/anicca/.openclaw/workspace/*/logs/*.log | head -10

# Read the failed job's log
tail -100 /Users/anicca/.openclaw/workspace/larry-trend-hunter/logs/2026-03-25.log
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What to look for in logs:

Item What to check
Exit code Non-zero = script failed
Error message Keywords: Error:, Uncaught, ECONNREFUSED
API response 401/403 (auth), 429 (rate limit), 500 (server)
Last execution time Did it actually run?

Step 4: Localize the Error

In today's case, errors were localized as follows:

Category Success Failure Pattern
Larry posts EN-side JA-side Trend hunter (X API) issue
ReelClaw All 4 None Video generation OK
Slideshow All EN + 2/3 JA JA first only Image API intermittent failure?
Analytics None 2 jobs app-metrics, daily-analytics

→ Hypothesis: JA-side X API token expired or hit rate limit

Step 5: Fix and Verify

Based on the hypothesis, apply the fix.

# Check token in .env
grep X_BEARER_TOKEN /Users/anicca/.openclaw/.env

# If expired, regenerate from X Developer Portal
# Update .env with new token
echo 'X_BEARER_TOKEN=<new-token>' >> /Users/anicca/.openclaw/.env

# Restart OpenClaw Gateway to apply
openclaw gateway restart
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After restart, either wait for the next cron run or trigger manually for immediate testing.

# Manual trigger (test without waiting)
openclaw cron run --job-id <failed-job-id>
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Key Takeaways

Lesson Detail
Localization is key Partial failure (not total) → find commonality (JA-side, analytics, etc.)
3-tier debugging sessions_list → sessions_history → direct logs
Mind token budget Fetching massive history hits constraints. Fetch only what you need
Error messages are sparse Cron reports binary "success"/"error". Details live elsewhere
Manual trigger for fast iteration Don't wait for next cron run. Fix → test immediately

Conclusion

When 6 out of 21 cron jobs fail, don't panic:

  1. sessions_list for overview
  2. sessions_history for failed job details
  3. If token-constrained, check direct log files
  4. Localize error patterns (EN vs JA, content vs analytics)
  5. Hypothesis → fix → manual trigger to verify

Partial failures are easier to debug than total failures. Find the common thread, and the root cause reveals itself.

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