claude-session-analysis

name	claude-session-analysis
description	Analyze Claude Code sessions to extract configuration improvements. Use when: (1) Want to optimize Claude Code setup (skills, permissions, CLAUDE.md), (2) Need to find what tools should be pre-granted (repeated permission requests), (3) Looking for skills to create (repeated investigation patterns), (4) Finding rules to add to CLAUDE.md (user corrections indicate missing guidance), (5) Diagnosing why sessions went poorly (compactions, interruptions). The goal is actionable improvements, not just metrics.
author	Claude Code
version	2.0.0
date	"2026-01-26T00:00:00.000Z"
tags	["optimization","sessions","skills","permissions","configuration"]

Claude Code Session Analysis

Problem

Sessions often have friction: repeated permission requests, investigation cycles, user corrections. Analyzing past sessions reveals what skills, permissions, and CLAUDE.md rules would have made the work smoother. The goal is configuration optimization, not just metrics.

Context / Trigger Conditions

Use this skill when:

• Want to improve Claude Code configuration based on past sessions
• Looking for tools that should be pre-granted (asked for repeatedly)
• Finding skills to create (same investigation done multiple times)
• Identifying rules for CLAUDE.md (user kept correcting same mistakes)
• Diagnosing why a session had many interruptions or compactions

Solution

1. Session File Locations

# Project-specific sessions
~/.claude/projects/-Users-USERNAME-Projects-PROJECT_NAME/

# Session files are named by UUID
SESSION_ID.jsonl                    # Main conversation
SESSION_ID/subagents/agent-*.jsonl  # Subagent conversations
SESSION_ID/tool-results/*.txt       # Large tool outputs

Finding sessions for a project:

# List all session directories for a project
ls -la ~/.claude/projects/-Users-cajias-Projects-PROJECT_NAME/

# Find sessions by date
ls -lt ~/.claude/projects/-Users-*-PROJECT/ | head -20

2. Session File Format

Each line is a JSON object with these key fields:

{
  "type": "user" | "assistant" | "file-history-snapshot" | "queue-operation",
  "message": {
    "role": "user" | "assistant",
    "content": [{"type": "text", "text": "..."} | {"type": "tool_use", ...}]
  },
  "timestamp": "ISO8601",
  "sessionId": "UUID"
}

3. Diagnostic Commands

Count context compactions:

grep -c "Conversation compacted" SESSION_FILE.jsonl

Find all sessions with compactions in a project:

grep -l "Conversation compacted" ~/.claude/projects/-Users-*-PROJECT/*.jsonl

Total compactions across all sessions:

grep -c "Conversation compacted" ~/.claude/projects/-Users-*-PROJECT/*.jsonl 2>/dev/null | \
  awk -F: '{s+=$2} END {print "Total compactions:", s}'

Extract user messages:

grep -h '"role":"user"' SESSION_FILE.jsonl | \
  grep -o '"text":"[^"]*"' | \
  head -20

Find user corrections/frustrations:

grep -h '"role":"user"' SESSION_FILE.jsonl | \
  grep -o '"text":"[^"]*"' | \
  grep -iE "forgot|skip|should have|already|told you|repeat|wrong|mistake|again"

Find repeated messages (indicates loops):

grep -h '"text":"[^"]*"' SESSION_FILE.jsonl | \
  sort | uniq -c | sort -rn | head -10

Find TDD-related patterns:

grep -o '"text":"[^"]*"' SESSION_FILE.jsonl | \
  grep -iE "RED|GREEN|REFACTOR|test first|write test|failing test"

4. Analyzing Context Compaction Impact

Find what was summarized:

# Look for summary type messages
grep '"type":"summary"' SESSION_FILE.jsonl | jq '.summary' 2>/dev/null

Find session continuation points:

grep -i "continued from a previous conversation" SESSION_FILE.jsonl

Identify compaction timing:

grep "Conversation compacted" SESSION_FILE.jsonl | \
  grep -o '"timestamp":"[^"]*"'

5. Subagent Analysis

List all subagents in a session:

ls ~/.claude/projects/-Users-*-PROJECT/SESSION_ID/subagents/

Find subagent that failed:

grep -l "error\|failed\|exception" SESSION_ID/subagents/*.jsonl

6. Python-Based Parsing (For Large/Complex Sessions)

When grep patterns fail on large sessions, use the Python scripts in scripts/ for reliable JSONL parsing.

Full session analysis (recommended):

SCRIPTS=~/.claude/skills/claude-session-analysis/scripts
python3 $SCRIPTS/session-stats.py SESSION.jsonl

Individual scripts:

# Extract tool usage counts
cat SESSION.jsonl | python3 $SCRIPTS/tool-usage.py

# Extract user messages (skips continuations)
cat SESSION.jsonl | python3 $SCRIPTS/user-messages.py --limit 20

# Extract compaction summaries
cat SESSION.jsonl | python3 $SCRIPTS/summaries.py

Scripts included:

• session-optimizer.py - Main script - extracts configuration recommendations
• session-stats.py - Comprehensive metrics with health assessment
• tool-usage.py - Tool usage frequency
• user-messages.py - User messages (with --limit and --include-continuations flags)
• summaries.py - Compaction summaries

7. Configuration Optimization (Primary Goal)

Run the optimizer script:

SCRIPTS=~/.claude/skills/claude-session-analysis/scripts
python3 $SCRIPTS/session-optimizer.py SESSION.jsonl

This extracts actionable recommendations:

• Tools to pre-grant - Commands requested 10+ times
• Skills to create - Investigation patterns that repeated
• CLAUDE.md rules - User corrections indicate missing guidance

What each finding means:

Finding	Action
Bash(glab *) requested 50x	Add to allowed tools in settings
"!reference" investigated 3x	Create a skill documenting the fix
User said "no, use X" 5x	Add rule to CLAUDE.md

8. Session Health Benchmarks

Metric	Healthy	Warning	Critical
Compactions	0-5	6-15	16+
Interruptions	0-3	4-8	9+
Duration	<1 day	1-7 days	>1 week

Interpretation:

• 44 compactions = extreme context debt, session should have been split
• 16+ interruptions = agent frequently going wrong direction
• Multi-week sessions = accumulated context loss makes later work unreliable

9. Pattern Recognition

Signs of lost context:

• Same exploration text repeated 3+ times
• User messages containing "again" or "already"
• Multiple identical tool calls in sequence
• Sudden shift from GREEN phase back to exploration

Signs of TDD violations:

• Implementation file edits without prior test file creation
• "Let me implement" without "tests are failing" context
• No RED/GREEN/REFACTOR pattern in todo items

Example Analysis

# Full diagnostic for a problematic session
SESSION="$HOME/.claude/projects/-Users-USERNAME-Projects-myproject/abc123.jsonl"

echo "=== Compaction Count ==="
grep -c "Conversation compacted" "$SESSION"

echo "=== User Corrections ==="
grep -h '"role":"user"' "$SESSION" | grep -o '"text":"[^"]*"' | \
  grep -iE "forgot|wrong|already" | head -5

echo "=== Repeated Messages ==="
grep -h '"text":"' "$SESSION" | sort | uniq -c | sort -rn | head -5

echo "=== TDD Phase Mentions ==="
grep -o '"text":"[^"]*"' "$SESSION" | grep -iE "RED|GREEN|REFACTOR" | head -5

Verification

Analysis is successful when you can answer:

1. Tools to pre-grant: What commands were requested 10+ times?
2. Skills to create: What topics were investigated repeatedly?
3. CLAUDE.md rules: What did the user keep correcting?
4. Session health: Was the session too long? Too many compactions?

Notes

• Session files can be large (100MB+) - use head or limit flags
• JSONL lines are often truncated in grep output - use Python scripts for full parsing
• Subagent files follow same format as main session
• Tool results may be stored separately in tool-results/ directory
• Timestamps are ISO8601 format, useful for correlating with git commits
• Scripts location: ~/.claude/skills/claude-session-analysis/scripts/