Log Analyzer
Parse application logs into actionable error digests with pattern grouping, severity classification, trend detection, and remediation recommendations.
Quick Start
# Analyze a single log file
python3 scripts/analyze_logs.py /var/log/app.log
# Analyze all logs in a directory
python3 scripts/analyze_logs.py /var/log/myapp/
# Last 24 hours only, errors and above
python3 scripts/analyze_logs.py /var/log/app.log --since 24h --severity error
# JSON output for programmatic use
python3 scripts/analyze_logs.py /var/log/app.log --output json
# Markdown report with trends
python3 scripts/analyze_logs.py /var/log/app.log --output markdown --trends
# Ignore noisy patterns
python3 scripts/analyze_logs.py /var/log/app.log --ignore "healthcheck" --ignore "GET /favicon"
Supported Formats (Auto-Detected)
- JSON structured — Bunyan, Winston, Pino, structlog, any
{"level": ..., "msg": ...} format
- Syslog — RFC 3164 (
Mar 28 02:31:00 host service: msg)
- Apache/Nginx access — Combined log format
- Nginx error —
2026/03/28 02:31:00 [error] ...
- Python tracebacks — Multi-line traceback collection
- Docker — ISO 8601 timestamps with container output
- Generic timestamped —
[2026-03-28 02:31:00] LEVEL: message
Force format with --format <name> if auto-detection fails.
What It Does
- Parses log entries with format auto-detection
- Classifies severity (TRACE → DEBUG → INFO → WARN → ERROR → FATAL)
- Normalizes messages (replaces UUIDs, IPs, timestamps, paths with placeholders)
- Groups similar errors by fingerprint to find recurring patterns
- Ranks by severity and frequency
- Detects trends with
--trends (hourly frequency buckets)
- Recommends fixes for 15+ known error patterns (OOM, connection refused, disk full, timeouts, SSL issues, rate limits, etc.)
Options
| Flag |
Default |
Description |
--format |
auto |
Force log format |
--since |
all |
Time filter (1h, 24h, 7d, or ISO date) |
--severity |
warn |
Minimum severity to report |
--top |
20 |
Number of top patterns to show |
--output |
text |
Output format: text, json, markdown |
--trends |
off |
Show hourly frequency trends |
--ignore |
none |
Regex patterns to exclude (repeatable) |
-q |
off |
Summary only, skip individual entries |
Exit Codes
0 — No errors found1 — Errors found (warn/error level)2 — Fatal/critical entries found
Use in CI/CD pipelines to fail builds on log errors.
Workflow
Incident Investigation
- Run with
--since 1h --severity error --trends to see recent errors with frequency
- Review top patterns — the most frequent errors are usually the root cause
- Check recommendations for known patterns
- Use
--output json to feed into monitoring dashboards
Periodic Health Check
- Run with
--since 24h --output markdown for a daily report
- Compare pattern counts across days to spot trends
- Set up as cron job for automated daily digests
Deep Dive
- Run with
--severity debug to see full picture
- Use
--ignore to filter out known noise
- Check
references/error-patterns.md for detailed remediation steps on specific error types
Error Pattern Reference
For detailed remediation guidance on specific error types (memory, network, database, SSL, etc.), see references/error-patterns.md.
1---2name: log-analyzer-23description: Analyze application logs to produce actionable error digests with pattern detection, severity classification, trend analysis, and remediation recommendations. Supports auto-detection of common log formats including syslog, JSON structured logs, Apache/Nginx access and error logs, Python tracebacks, Node.js errors, Docker logs, and generic timestamped formats. Use when asked to analyze logs, debug errors from log files, find recurring issues in logs, create error reports from log data, investigate production incidents from logs, summarize log output, identify error patterns, check application health from logs, or parse server logs. Triggers on "analyze logs", "check logs", "log errors", "error digest", "parse logs", "log report", "what's failing", "production errors", "log summary", "incident analysis", "error patterns".4---56# Log Analyzer78Parse application logs into actionable error digests with pattern grouping, severity classification, trend detection, and remediation recommendations.910## Quick Start1112```bash13# Analyze a single log file14python3 scripts/analyze_logs.py /var/log/app.log1516# Analyze all logs in a directory17python3 scripts/analyze_logs.py /var/log/myapp/1819# Last 24 hours only, errors and above20python3 scripts/analyze_logs.py /var/log/app.log --since 24h --severity error2122# JSON output for programmatic use23python3 scripts/analyze_logs.py /var/log/app.log --output json2425# Markdown report with trends26python3 scripts/analyze_logs.py /var/log/app.log --output markdown --trends2728# Ignore noisy patterns29python3 scripts/analyze_logs.py /var/log/app.log --ignore "healthcheck" --ignore "GET /favicon"30```3132## Supported Formats (Auto-Detected)3334- **JSON structured** — Bunyan, Winston, Pino, structlog, any `{"level": ..., "msg": ...}` format35- **Syslog** — RFC 3164 (`Mar 28 02:31:00 host service: msg`)36- **Apache/Nginx access** — Combined log format37- **Nginx error** — `2026/03/28 02:31:00 [error] ...`38- **Python tracebacks** — Multi-line traceback collection39- **Docker** — ISO 8601 timestamps with container output40- **Generic timestamped** — `[2026-03-28 02:31:00] LEVEL: message`4142Force format with `--format <name>` if auto-detection fails.4344## What It Does45461. **Parses** log entries with format auto-detection472. **Classifies** severity (TRACE → DEBUG → INFO → WARN → ERROR → FATAL)483. **Normalizes** messages (replaces UUIDs, IPs, timestamps, paths with placeholders)494. **Groups** similar errors by fingerprint to find recurring patterns505. **Ranks** by severity and frequency516. **Detects trends** with `--trends` (hourly frequency buckets)527. **Recommends fixes** for 15+ known error patterns (OOM, connection refused, disk full, timeouts, SSL issues, rate limits, etc.)5354## Options5556| Flag | Default | Description |57|------|---------|-------------|58| `--format` | auto | Force log format |59| `--since` | all | Time filter (`1h`, `24h`, `7d`, or ISO date) |60| `--severity` | warn | Minimum severity to report |61| `--top` | 20 | Number of top patterns to show |62| `--output` | text | Output format: text, json, markdown |63| `--trends` | off | Show hourly frequency trends |64| `--ignore` | none | Regex patterns to exclude (repeatable) |65| `-q` | off | Summary only, skip individual entries |6667## Exit Codes6869- `0` — No errors found70- `1` — Errors found (warn/error level)71- `2` — Fatal/critical entries found7273Use in CI/CD pipelines to fail builds on log errors.7475## Workflow7677### Incident Investigation78791. Run with `--since 1h --severity error --trends` to see recent errors with frequency802. Review top patterns — the most frequent errors are usually the root cause813. Check recommendations for known patterns824. Use `--output json` to feed into monitoring dashboards8384### Periodic Health Check85861. Run with `--since 24h --output markdown` for a daily report872. Compare pattern counts across days to spot trends883. Set up as cron job for automated daily digests8990### Deep Dive91921. Run with `--severity debug` to see full picture932. Use `--ignore` to filter out known noise943. Check `references/error-patterns.md` for detailed remediation steps on specific error types9596## Error Pattern Reference9798For detailed remediation guidance on specific error types (memory, network, database, SSL, etc.), see `references/error-patterns.md`.
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