Market Breadth Analyzer Skill

Purpose

Quantify market breadth health using a data-driven 6-component scoring system (0-100). Uses TraderMonty's publicly available CSV data to measure how broadly the market is participating in a rally or decline.

Score direction: 100 = Maximum health (broad participation), 0 = Critical weakness.

No API key required - uses freely available CSV data from GitHub Pages.

When to Use This Skill

English:

• User asks "Is the market rally broad-based?" or "How healthy is market breadth?"
• User wants to assess market participation rate
• User asks about advance-decline indicators or breadth thrust
• User wants to know if the market is narrowing (fewer stocks participating)
• User asks about equity exposure levels based on breadth conditions

Japanese:

• 「マーケットブレッドスはどうですか？」「市場の参加率は？」
• 「上昇は広がっている？」「一部の銘柄だけの上昇？」
• ブレッドス指標に基づくエクスポージャー判断
• 市場の健康度をデータで確認したい

Difference from Breadth Chart Analyst

Aspect	Market Breadth Analyzer	Breadth Chart Analyst
Data Source	CSV (automated)	Chart images (manual)
API Required	None	None
Output	Quantitative 0-100 score	Qualitative chart analysis
Components	6 scored dimensions	Visual pattern recognition
Repeatability	Fully reproducible	Analyst-dependent

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Execution Workflow

Phase 1: Execute Python Script

Run the analysis script:

python3 skills/market-breadth-analyzer/scripts/market_breadth_analyzer.py \
  --detail-url "https://tradermonty.github.io/market-breadth-analysis/market_breadth_data.csv" \
  --summary-url "https://tradermonty.github.io/market-breadth-analysis/market_breadth_summary.csv"

The script will:

1. Fetch detail CSV (~2,500 rows, 2016-present) and summary CSV (8 metrics)
2. Validate data freshness (warn if > 5 days old)
3. Calculate all 6 component scores (with automatic weight redistribution if any component lacks data)
4. Generate composite score with zone classification
5. Track score history and compute trend (improving/deteriorating/stable)
6. Output JSON and Markdown reports

Phase 2: Present Results

Present the generated Markdown report to the user, highlighting:

• Composite score and health zone
• Strongest and weakest components
• Recommended equity exposure level
• Key breadth levels to watch
• Any data freshness warnings

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6-Component Scoring System

#	Component	Weight	Key Signal
1	Breadth Level & Trend	25%	Current 8MA level + 200MA trend direction + 8MA direction modifier
2	8MA vs 200MA Crossover	20%	Momentum via MA gap and direction
3	Peak/Trough Cycle	20%	Position in breadth cycle
4	Bearish Signal	15%	Backtested bearish signal flag
5	Historical Percentile	10%	Current vs full history distribution
6	S&P 500 Divergence	10%	Multi-window (20d + 60d) price vs breadth divergence

Weight Redistribution: If any component lacks sufficient data (e.g., no peak/trough markers detected), it is excluded and its weight is proportionally redistributed among the remaining components. The report shows both original and effective weights.

Score History: Composite scores are persisted across runs (keyed by data date). The report includes a trend summary (improving/deteriorating/stable) when multiple observations are available.

Health Zone Mapping (100 = Healthy)

Score	Zone	Equity Exposure	Action
80-100	Strong	90-100%	Full position, growth/momentum favored
60-79	Healthy	75-90%	Normal operations
40-59	Neutral	60-75%	Selective positioning, tighten stops
20-39	Weakening	40-60%	Profit-taking, raise cash
0-19	Critical	25-40%	Capital preservation, watch for trough

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Data Sources

Detail CSV: market_breadth_data.csv

• ~2,500 rows from 2016-02 to present
• Columns: Date, S&P500_Price, Breadth_Index_Raw, Breadth_Index_200MA, Breadth_Index_8MA, Breadth_200MA_Trend, Bearish_Signal, Is_Peak, Is_Trough, Is_Trough_8MA_Below_04

Summary CSV: market_breadth_summary.csv

• 8 aggregate metrics (average peaks, average troughs, counts, analysis period)

Both are publicly hosted on GitHub Pages - no authentication required.

Output Files

• JSON: market_breadth_YYYY-MM-DD_HHMMSS.json
• Markdown: market_breadth_YYYY-MM-DD_HHMMSS.md
• History: market_breadth_history.json (persists across runs, max 20 entries)

Reference Documents

references/breadth_analysis_methodology.md

• Full methodology with component scoring details
• Threshold explanations and zone definitions
• Historical context and interpretation guide

When to Load References

• First use: Load methodology reference for framework understanding
• Regular execution: References not needed - script handles scoring