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analyze-log-files

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Analyze log files by stripping ANSI escape sequences first. Use when asked to process, handle, read, or analyze log files that may contain terminal escape codes.

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How to use this skill

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Source SKILL.md: https://github.com/r3bl-org/r3bl-open-core/blob/HEAD/.agents/skills/analyze-log-files/SKILL.md

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Analyze Log Files

When to Use

  • When user asks to "analyze /tmp/r3bl_tui/log.txt", "read the log file", "process logs", "check the logs"
  • When dealing with any .log or log-related files that may contain ANSI escape sequences
  • When terminal output has been captured to a file and needs analysis
  • When log files appear garbled or contain escape sequence artifacts

Why This Matters

Log files captured from terminal sessions often contain ANSI escape sequences for:

  • Colors (e.g., \x1b[31m for red)
  • Cursor movements
  • Text formatting (bold, underline)
  • Screen clearing commands

These sequences make logs difficult to:

  1. Read in plain text editors
  2. Search with grep/ripgrep
  3. Process with text analysis tools
  4. Analyze accurately by LLMs

Instructions

Step 1: Strip ANSI Escape Sequences

Before analyzing any log file, first strip the ANSI sequences using ansifilter:

ansifilter -i /tmp/r3bl_tui/log.txt -o /tmp/clean_log.txt

For other log file names, adjust accordingly:

ansifilter -i <input_file> -o /tmp/clean_log.txt

Step 2: Analyze the Clean Log

Read and analyze /tmp/clean_log.txt instead of the original file:

# Use the Read tool on /tmp/clean_log.txt

Step 3: Report Findings

When reporting findings to the user:

  • Reference line numbers from the clean log
  • Quote relevant sections
  • Summarize errors, warnings, or patterns found

Common Log File Locations

  • /tmp/r3bl_tui/log.txt - General purpose log in project root
  • target/ - Cargo build logs
  • /tmp/*.log - Temporary logs

Example Workflow

User: "Can you analyze /tmp/r3bl_tui/log.txt and tell me what's wrong?"

  1. Run: ansifilter -i /tmp/r3bl_tui/log.txt -o /tmp/clean_log.txt
  2. Read: /tmp/clean_log.txt
  3. Analyze the content for errors, warnings, patterns
  4. Report findings to user

Troubleshooting

If ansifilter is not installed:

# Ubuntu/Debian
sudo apt-get install ansifilter

# macOS
brew install ansifilter

# Or run bootstrap.sh to install all dependencies
./bootstrap.sh

Related Skills

  • check-code-quality - For checking Rust code quality (may generate logs)
  • analyze-performance - For performance analysis (generates flamegraph data)

Related Commands

  • /analyze-logs - Explicitly invokes this skill