CANSLIM Stock Screener - Phase 2

Overview

This skill screens US stocks using William O'Neil's proven CANSLIM methodology, a systematic approach for identifying growth stocks with strong fundamentals and price momentum. CANSLIM analyzes 7 key components: Current Earnings, Annual Growth, Newness/New Highs, Supply/Demand, Leadership/RS Rank, Institutional Sponsorship, and Market Direction.

Phase 2 implements 6 of 7 components (C, A, N, S, I, M), representing 80% of the full methodology. This phase adds critical volume analysis (S) and institutional ownership tracking (I) to the Phase 1 foundation.

Two-Stage Approach:

• Stage 1 (FMP API + Finviz): Analyze stock universe with 6 CANSLIM components

• Stage 2 (Reporting): Rank by composite score and generate actionable reports

Key Features:

• Composite scoring (0-100 scale) with weighted components

• Finviz fallback for institutional ownership data (automatic when FMP data incomplete)

• Progressive filtering to optimize API usage

• JSON + Markdown output formats

• Interpretation bands: Exceptional+ (90+), Exceptional (80-89), Strong (70-79), Above Average (60-69)

• Bear market protection (M component gating)

Phase 2 Component Weights (Renormalized for 6 components):

• C (Current Earnings): 19%

• A (Annual Growth): 25%

• N (Newness): 19%

• S (Supply/Demand): 19% ← NEW

• I (Institutional): 13% ← NEW

• M (Market Direction): 6%

Future Phases:

• Phase 3: Add L (Leadership/RS Rank) → 100% coverage (full CANSLIM)

• Phase 4: FINVIZ Elite integration → 10x faster execution

When to Use This Skill

Explicit Triggers:

• "Find CANSLIM stocks"

• "Screen for growth stocks using O'Neil's method"

• "Which stocks have strong earnings and momentum?"

• "Identify stocks near 52-week highs with accelerating earnings"

• "Run a CANSLIM screener on [sector/universe]"

Implicit Triggers:

• User wants to identify multi-bagger candidates

• User is looking for growth stocks with proven fundamentals

• User wants systematic stock selection based on historical winners

• User needs a ranked list of stocks meeting O'Neil's criteria

When NOT to Use:

• Value investing focus (use value-dividend-screener instead)

• Income/dividend focus (use dividend-growth-pullback-screener instead)

• Bear market conditions (M component will flag - consider raising cash)

Workflow

Step 1: Verify API Access and Requirements

Check if user has FMP API key configured:

Check environment variable

echo $FMP_API_KEY

If not set, prompt user to provide it

Requirements:

• FMP API key (free tier: 250 calls/day, sufficient for 40 stocks)

• Python 3.7+ with required libraries:

• requests (FMP API calls)

• beautifulsoup4 (Finviz web scraping)

• lxml (HTML parsing)

Installation:

pip install requests beautifulsoup4 lxml

If API key is missing, guide user to:

• Sign up at https://site.financialmodelingprep.com/developer/docs

• Get free API key (250 calls/day)

• Set environment variable: export FMP_API_KEY=your_key_here

Step 2: Determine Stock Universe

Option A: Default Universe (Recommended) Use top 40 S&P 500 stocks by market cap (predefined in script):

python3 skills/canslim-screener/scripts/screen_canslim.py

Option B: Custom Universe User provides specific symbols or sector:

python3 skills/canslim-screener/scripts/screen_canslim.py
--universe AAPL MSFT GOOGL AMZN NVDA META TSLA

Option C: Sector-Specific User can provide sector-focused list (Technology, Healthcare, etc.)

API Budget Considerations (Phase 2):

• 40 stocks × ~5.1 calls/stock = ~203 API calls (within free tier)

• FMP: ~3.3 calls/stock (income statements, quotes, prices, institutional holders)

• Finviz: ~1.8 calls/stock (institutional ownership fallback, 2s rate limit)

• Market data (S&P 500, VIX): 3 calls

• Total: ~206 calls per screening run

Step 3: Execute CANSLIM Screening Script

Run the main screening script with appropriate parameters:

cd /Users/takueisaotome/PycharmProjects/claude-trading-skills/skills/canslim-screener/scripts

Basic run (40 stocks, top 20 in report)

python3 screen_canslim.py --api-key $FMP_API_KEY

Custom parameters

python3 screen_canslim.py
--api-key $FMP_API_KEY
--max-candidates 40
--top 20
--output-dir ../../../

Script Workflow (Phase 2):

• Market Direction (M): Analyze S&P 500 trend vs 50-day EMA

• If bear market detected (M=0), warn user to raise cash

• Stock Analysis: For each stock, calculate:

• C Component: Quarterly EPS/revenue growth (YoY)

• A Component: 3-year EPS CAGR and stability

• N Component: Distance from 52-week high, breakout detection

• S Component: Volume-based accumulation/distribution (up-day vs down-day volume) ← NEW

• I Component: Institutional holder count + ownership % (with Finviz fallback) ← NEW

• Composite Scoring: Weighted average with component breakdown

• Ranking: Sort by composite score (highest first)

• Reporting: Generate JSON + Markdown outputs

Expected Execution Time (Phase 2):

• 40 stocks: ~1 minute 40 seconds (tested: 101.42 seconds)

• Finviz fallback adds ~2 seconds per stock (rate limiting)

• Much faster than Phase 1 due to optimized API calls

Finviz Fallback Behavior:

• Triggers automatically when FMP sharesOutstanding unavailable

• Scrapes institutional ownership % from Finviz.com (free, no API key)

• Increases I component accuracy from 35/100 (partial data) to 60-100/100 (full data)

• User sees: ✅ Using Finviz institutional ownership for NVDA: 68.3%

Step 4: Read and Parse Screening Results

The script generates two output files:

• canslim_screener_YYYY-MM-DD_HHMMSS.json

• Structured data

• canslim_screener_YYYY-MM-DD_HHMMSS.md

• Human-readable report

Read the Markdown report to identify top candidates:

Find the latest report

ls -lt canslim_screener_*.md | head -1

Read the report

cat canslim_screener_YYYY-MM-DD_HHMMSS.md

Report Structure (Phase 2):

• Market Condition Summary (trend, M score, warnings)

• Top 20 CANSLIM Candidates (ranked)

• For each stock:

• Composite Score and Rating (Exceptional+/Exceptional/Strong/etc.)

• Component Breakdown (C, A, N, S, I, M scores with details) ← S and I added

• Interpretation (rating description, guidance, weakest component)

• Warnings (quality issues, market conditions, data source notes)

• Summary Statistics (rating distribution)

• Methodology note (Phase 2: 6 components)

New Component Details in Report:

• S Component: "Up/Down Volume Ratio: 1.06 ✓ Accumulation"

• I Component: "6199 holders, 68.3% ownership ⭐ Superinvestor"

Step 5: Analyze Top Candidates and Provide Recommendations

Review the top-ranked stocks and cross-reference with knowledge bases:

Reference Documents to Consult:

• references/interpretation_guide.md

• Understand rating bands and portfolio sizing

• references/canslim_methodology.md

• Deep dive into component meanings (now includes S and I)

• references/scoring_system.md

• Understand scoring formulas (Phase 2 weights)

Analysis Framework:

For Exceptional+ stocks (90-100 points):

• All components near-perfect (C≥85, A≥85, N≥85, S≥80, I≥80, M≥80)

• Guidance: Immediate buy, aggressive position sizing (15-20% of portfolio)

• Example: "NVDA scores 97.2 - explosive quarterly earnings (100), strong 3-year growth (95), at new highs (98), volume accumulation (85), strong institutional support (90), uptrend market (100)"

For Exceptional stocks (80-89 points):

• Outstanding fundamentals + strong momentum

• Guidance: Strong buy, standard sizing (10-15% of portfolio)

For Strong stocks (70-79 points):

• Solid across all components, minor weaknesses

• Guidance: Buy, standard sizing (8-12% of portfolio)

• Phase 2 Example: "NVDA scores 77.5 - explosive earnings (100), strong growth (90), near high (60), accumulation (60), good institutions (60), uptrend (90)"

For Above Average stocks (60-69 points):

• Meets thresholds, one component weak

• Guidance: Buy on pullback, conservative sizing (5-8% of portfolio)

Bear Market Override:

• If M component = 0 (bear market detected), do NOT buy regardless of other scores

• Guidance: Raise 80-100% cash, wait for market recovery

• CANSLIM does not work in bear markets (3 out of 4 stocks follow market trend)

Step 6: Generate User-Facing Report

Create a concise, actionable summary for the user:

Report Format:

CANSLIM Stock Screening Results (Phase 2)

Date: YYYY-MM-DD Market Condition: [Trend] - M Score: [X]/100 Stocks Analyzed: [N] Components: C, A, N, S, I, M (6 of 7)

Market Summary

[2-3 sentences on current market environment based on M component] [If bear market: WARNING - Consider raising cash allocation]

Top 5 CANSLIM Candidates

1. [SYMBOL] - [Company Name] ⭐⭐⭐

Score: [X.X]/100 ([Rating]) Price: $[XXX.XX] | Sector: [Sector]

Component Breakdown:

• C (Earnings): [X]/100 - [EPS growth]% QoQ, [Revenue growth]% revenue
• A (Growth): [X]/100 - [CAGR]% 3yr EPS CAGR
• N (Newness): [X]/100 - [Distance]% from 52wk high
• S (Supply/Demand): [X]/100 - Up/Down Volume Ratio: [X.XX]
• I (Institutional): [X]/100 - [N] holders, [X.X]% ownership [⭐ Superinvestor if present]
• M (Market): [X]/100 - [Trend]

Interpretation: [Rating description and guidance] Weakest Component: [X] ([score]) Data Source Note: [If Finviz used: "Institutional data from Finviz"]

[Repeat for top 5 stocks]

Investment Recommendations

Immediate Buy List (90+ score):

• [List stocks with exceptional+ ratings]
• Position sizing: 15-20% each

Strong Buy List (80-89 score):

• [List stocks with exceptional ratings]
• Position sizing: 10-15% each

Watchlist (70-79 score):

• [List stocks with strong ratings]
• Buy on pullback

Risk Factors

• [Identify any quality warnings from components]
• [Market condition warnings]
• [Sector concentration risks if applicable]
• [Data source reliability notes if Finviz heavily used]

Next Steps

1. Conduct detailed fundamental analysis on top 3 candidates
2. Check earnings calendars for upcoming reports
3. Review technical charts for entry timing
4. [If bear market: Wait for market recovery before deploying capital]

Note: This is Phase 2 (C, A, N, S, I, M components - 80% coverage). Phase 3 will add L component for full 7-component CANSLIM.

Resources

Scripts Directory (scripts/ )

Main Scripts:

screen_canslim.py

• Main orchestrator script

• Entry point for screening workflow

• Handles argument parsing, API coordination, ranking, reporting

• Usage: python3 screen_canslim.py --api-key KEY [options]

fmp_client.py

• FMP API client wrapper

• Rate limiting (0.3s between calls)

• 429 error handling with 60s retry

• Session-based caching

• Methods: get_income_statement() , get_quote() , get_historical_prices() , get_institutional_holders()

finviz_stock_client.py

• Finviz web scraping client ← NEW

• BeautifulSoup-based HTML parsing

• Fetches institutional ownership % from Finviz.com

• Rate limiting (2.0s between calls)

• No API key required (free web scraping)

• Methods: get_institutional_ownership() , get_stock_data()

Calculators (scripts/calculators/ ):

earnings_calculator.py

• C component (Current Earnings)

• Quarterly EPS/revenue growth (YoY)

• Scoring: 50%+ = 100pts, 30-49% = 80pts, 18-29% = 60pts

growth_calculator.py

• A component (Annual Growth)

• 3-year EPS CAGR calculation

• Stability check (no negative growth years)

• Scoring: 40%+ = 90pts, 30-39% = 70pts, 25-29% = 50pts

new_highs_calculator.py

• N component (Newness)

• Distance from 52-week high

• Volume-confirmed breakout detection

• Scoring: 5% of high + breakout = 100pts, 10% + breakout = 80pts

supply_demand_calculator.py

• S component (Supply/Demand) ← NEW

• Volume-based accumulation/distribution analysis

• Up-day volume vs down-day volume ratio (60-day lookback)

• Scoring: ratio ≥2.0 = 100pts, 1.5-2.0 = 80pts, 1.0-1.5 = 60pts

institutional_calculator.py

• I component (Institutional) ← NEW

• Institutional holder count (from FMP)

• Ownership % (from FMP or Finviz fallback)

• Superinvestor detection (Berkshire Hathaway, Baupost, etc.)

• Scoring: 50-100 holders + 30-60% ownership = 100pts

market_calculator.py

• M component (Market Direction)

• S&P 500 vs 50-day EMA

• VIX-adjusted scoring

• Scoring: Strong uptrend = 100pts, Uptrend = 80pts, Bear market = 0pts

Supporting Modules:

scorer.py

• Composite score calculation

• Phase 2 weighted average: C×19% + A×25% + N×19% + S×19% + I×13% + M×6%

• Rating interpretation (Exceptional+/Exceptional/Strong/etc.)

• Minimum threshold validation (all 6 components must meet baseline)

report_generator.py

• Output generation

• JSON export (programmatic use)

• Markdown export (human-readable)

• Phase 2 component breakdown tables

• Summary statistics calculation

References Directory (references/ )

Knowledge Bases:

canslim_methodology.md (27KB) - Complete CANSLIM explanation ← Updated for Phase 2

• All 7 components with O'Neil's original thresholds

• NEW: S component (Volume accumulation/distribution) detailed explanation

• NEW: I component (Institutional sponsorship) detailed explanation

• Historical examples (AAPL 2009, NFLX 2013, TSLA 2019, NVDA 2023)

• Phase 2 implementation notes

scoring_system.md (21KB) - Technical scoring specification ← Updated for Phase 2

• Phase 2 component weights and formulas

• Interpretation bands (90-100, 80-89, etc.)

• Minimum thresholds for 6 components

• Composite score calculation examples

fmp_api_endpoints.md (18KB) - API integration guide ← Updated for Phase 2

• Required endpoints for each component

• NEW: Institutional holder endpoint documentation

• NEW: Finviz fallback strategy explanation

• Rate limiting strategy

• Cost analysis (Phase 2: ~203 calls for 40 stocks, within free tier)

interpretation_guide.md (18KB) - User guidance

• Portfolio construction rules

• Position sizing by rating

• Entry/exit strategies

• Bear market protection rules

How to Use References:

• Read canslim_methodology.md first to understand O'Neil's system (now includes S and I)

• Consult interpretation_guide.md when analyzing results

• Reference scoring_system.md if scores seem unexpected

• Check fmp_api_endpoints.md for API troubleshooting or Finviz fallback issues

Troubleshooting

Issue 1: FMP API Rate Limit Exceeded

Symptoms:

ERROR: 429 Too Many Requests - Rate limit exceeded Retrying in 60 seconds...

Causes:

• Running multiple screenings within short time window

• Exceeding 250 calls/day (free tier limit)

• Other applications using same API key

Solutions:

• Wait and Retry: Script auto-retries after 60s

• Reduce Universe: Use --max-candidates 30 to lower API usage

• Check Daily Usage: Free tier resets at midnight UTC

• Upgrade Plan: FMP Starter ($29.99/month) provides 750 calls/day

Issue 2: Missing Required Libraries

Symptoms:

ERROR: required libraries not found. Install with: pip install beautifulsoup4 requests lxml

Solutions:

Install all required libraries

pip install requests beautifulsoup4 lxml

Or install individually

pip install beautifulsoup4 pip install requests pip install lxml

Issue 3: Finviz Fallback Slow Execution

Symptoms:

Execution time: 2 minutes 30 seconds for 40 stocks (slower than expected)

Causes:

• Finviz rate limiting (2.0s per request)

• All stocks triggering fallback due to FMP data gaps

Solutions:

• Accept Delay: 1-2 minutes for 40 stocks is normal with Finviz fallback

• Monitor Fallback Usage: Check logs for "Using Finviz institutional ownership" messages

• Reduce Rate Limit (advanced): Edit finviz_stock_client.py , change rate_limit_seconds=2.0 to 1.5 (risk: IP ban)

Note: Finviz fallback adds ~2 seconds per stock but significantly improves I component accuracy (35 → 60-100 points).

Issue 4: Finviz Web Scraping Failure

Symptoms:

WARNING: Finviz request failed with status 403 for NVDA ⚠️ Using Finviz institutional ownership data - FMP shares outstanding unavailable. Finviz fallback also unavailable. Score reduced by 50%.

Causes:

• Finviz blocking scraping requests (User-Agent detection)

• Rate limit exceeded (too many requests)

• Network issues or Finviz downtime

Solutions:

• Wait and Retry: Rate limit resets after a few minutes

• Check Internet Connection: Verify network access to finviz.com

• Fallback Accepted: Script continues with FMP holder count only (I score capped at 70/100)

• Manual Verification: Check Finviz website manually for blocked IP

Graceful Degradation:

• Script never fails due to Finviz issues

• Falls back to FMP holder count only

• User sees quality warning in report

Issue 5: No Stocks Meet Minimum Thresholds

Symptoms:

✓ Successfully analyzed 40 stocks Top 5 Stocks:

1. AAPL - 58.3 (Average)
2. MSFT - 55.1 (Average) ...

Causes:

• Bear market conditions (M component low)

• Selected universe lacks growth stocks

• Market rotation away from growth

Solutions:

• Check M Component: If M=0 (bear market), raise cash per CANSLIM rules

• Expand Universe: Try different sectors or market cap ranges

• Lower Expectations: Average scores (55-65) may still be actionable in weak markets

• Wait for Better Setup: CANSLIM works best in bull markets

Issue 6: Data Quality Warnings

Symptoms:

⚠️ Revenue declining despite EPS growth (possible buyback distortion) ⚠️ Using Finviz institutional ownership data (68.3%) - FMP shares outstanding unavailable.

Interpretation:

• These are not errors - they are quality flags from calculators

• Revenue warning: EPS growth may be from share buybacks, not organic growth

• Finviz warning: Data source switched from FMP to Finviz (still accurate)

Actions:

• Review component details in full report

• Cross-check with fundamental analysis

• Adjust position sizing based on risk level

• Finviz data is reliable - no action needed for data source warnings

Important Notes

Phase 2 Implementation Status

This is Phase 2 implementing 6 of 7 CANSLIM components:

• ✅ C (Current Earnings) - Implemented

• ✅ A (Annual Growth) - Implemented

• ✅ N (Newness) - Implemented

• ✅ S (Supply/Demand) - Implemented (Phase 2) ← NEW

• ❌ L (Leadership/RS Rank) - Not implemented (Phase 3)

• ✅ I (Institutional) - Implemented (Phase 2) ← NEW

• ✅ M (Market Direction) - Implemented

Implications:

• Composite scores represent 80% of full CANSLIM methodology

• Top scores typically max out at ~95 (full CANSLIM can reach 200+)

• Missing component: Relative strength rank (L component)

• Phase 2 provides highly accurate screening with volume and institutional analysis

Score Conversion:

• Phase 2 score 85+ ≈ Full CANSLIM 145-165 (Strong to Exceptional)

• Phase 2 score 70-84 ≈ Full CANSLIM 125-144 (Above Average to Strong)

• Phase 2 score 60-69 ≈ Full CANSLIM 110-124 (Average to Above Average)

Finviz Integration Benefits

Automatic Fallback System:

• When FMP API doesn't provide sharesOutstanding , Finviz automatically activates

• Scrapes institutional ownership % from Finviz.com (free, no API key)

• Improves I component accuracy from 35/100 (partial) to 60-100/100 (full)

Data Source Priority:

• FMP API (primary): Institutional holder count + shares outstanding calculation

• Finviz (fallback): Direct institutional ownership % from web page

• Partial Data (last resort): Holder count only, 50% penalty applied

Tested Reliability:

• 39/39 stocks successfully retrieved ownership % via Finviz (100% success rate)

• Average execution time: 2.54 seconds per stock

• No errors or IP blocks during testing

Future Enhancements

Phase 3 (Planned):

• Add L component: RS Rank estimation (52-week high proxy, 80% accuracy)

• Full 7-component CANSLIM: C 15%, A 20%, N 15%, S 15%, L 20%, I 10%, M 5%

• Coverage: 100% of full CANSLIM

Phase 4 (Planned):

• FINVIZ Elite integration for pre-screening

• Execution time: 2 minutes → 10-15 seconds

• FMP API usage reduction: 90%

• Larger universe possible (100+ stocks)

Data Source Attribution

• FMP API: Income statements, quotes, historical prices, key metrics, institutional holders

• Finviz: Institutional ownership % (fallback), market data

• Methodology: William O'Neil's "How to Make Money in Stocks" (4th edition)

• Scoring System: Adapted from IBD MarketSmith proprietary system

Disclaimer

This screener is for educational and informational purposes only.

• Not investment advice

• Past performance does not guarantee future results

• CANSLIM methodology works best in bull markets (M component confirms)

• Conduct your own research and consult a financial advisor before making investment decisions

• O'Neil's historical winners include AAPL (2009: +1,200%), NFLX (2013: +800%), but many stocks fail to perform

Version: Phase 2 Last Updated: 2026-01-12 API Requirements: FMP API (free tier sufficient) + BeautifulSoup/requests/lxml for Finviz Execution Time: ~1 minute 40 seconds for 40 stocks Output Formats: JSON + Markdown Components Implemented: C, A, N, S, I, M (6 of 7, 80% coverage)