Context Analyzer

jbdamask/john-claude-skills

29 repo stars
Updated July 31, 2026
jbdamask/john-claude-skills

Analyze Claude Code session JSONL to find what bloats the context window — image usage, file re-reads, tool-output volume — and get optimization recommendations.

About

Context-analyzer parses Claude Code chat-history JSONL files to identify what is consuming the context window — heavy image usage, repeated file reads, and large tool outputs. It then reports the worst offenders and recommends optimizations to keep sessions lean. Useful for power users diagnosing slow or expensive agent sessions.

Parses JSONL session files
Flags context-window bloat
Reports image and re-read usage
Optimization recommendations

Context Analyzer by the numbers

Data as of Aug 1, 2026 (Skillselion catalog sync)

/plugin marketplace add jbdamask/john-claude-skills

/plugin install context-analyzer@john-claude-skills

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repo stars	★ 29
Last updated	July 31, 2026
Repository	jbdamask/john-claude-skills ↗

What it does

Analyze Claude Code session JSONL to find what bloats the context window — image usage, file re-reads, tool-output volume — and get optimization recommendations.

README.md

context-analyzer

A Claude Code plugin that analyzes chat history to identify what's consuming your context window and provides optimization recommendations.

Features

Context breakdown — Categorizes context consumption by type (images, file reads, bash output, screenshots, etc.)
File re-read detection — Identifies files that are read repeatedly across sessions, wasting context
Largest session analysis — Finds which sessions consumed the most context and why
Actionable recommendations — Provides prioritized suggestions to reduce context bloat
Auto-detection — Automatically finds the project history directory from your current working directory

Components

Component	Name	Description
Command	`/context-analyzer:analyze-context`	Run the full analysis and get a report
Agent	`context-analyzer`	Subagent for autonomous context diagnostics
Skill	Context Optimization	Knowledge about context optimization patterns
Script	`analyze_context.py`	Python analysis engine (no dependencies beyond stdlib)

Installation

From a marketplace

/plugin install context-analyzer@your-marketplace

Local testing

claude --plugin-dir /path/to/context-analyzer

Usage

Slash command

/context-analyzer:analyze-context

Runs the analysis on the current project and presents a formatted report.

Agent (automatic)

The context-analyzer agent triggers when you ask questions like:

"Why is my context filling up?"
"Analyze my context usage"
"What's consuming my context window?"

Direct script execution

# Markdown report (default)
python3 scripts/analyze_context.py ~/.claude/projects/-Your-Project-Path/

# JSON output for programmatic use
python3 scripts/analyze_context.py ~/.claude/projects/-Your-Project-Path/ --json

Prerequisites

Python 3.8+ (uses only stdlib — no pip install needed)
Claude Code chat history in ~/.claude/projects/

How It Works

The plugin parses JSONL chat history files that Claude Code stores in ~/.claude/projects/{encoded-project-path}/. Each line is a JSON message representing a conversation event. The analyzer categorizes every message into context consumption buckets and tracks file read patterns across all sessions.

See skills/context-optimization/references/analysis-methodology.md for details.