| name | base-breakout-scan |
| description | Scan US large-cap equities for valid pre-breakout bases — tight consolidations after a prior advance, with squeeze + volume dry-up + rising relative strength. Use when the user wants to find stocks about to break out, identify coiled / VCP / cup-and-handle setups, or find Minervini Trend Template + base setups. Triggers on 'find breakout candidates', 'stocks setting up', 'compressed bases', 'tight ranges', 'ready to pop', 'near 52-week highs', 'VCP setups', 'coiled'. The natural complement to momentum-scan — that one finds what's already running; this finds what's about to. Do NOT use for single-ticker chart analysis, ETF screening, value/contrarian picks, or generic explanations of base-and-breakout investing. |
base-breakout-scan
Find US equities in valid pre-breakout bases — tight consolidations near 52-week highs after a prior advance, with quality metrics (Bollinger Band squeeze, volume dry-up, rising relative strength) showing the setup is "loaded". Surface a daily watchlist of which names are 🚀 breaking out today, 🔥 imminent, ⏳ coiled, or 📊 still forming, and track which setups persist across runs.
The natural sibling of momentum-scan: that one finds what's already running (high trailing return); this one finds what's about to run (the build-up before the move). They filter for opposite price patterns by design — momentum-scan's --min-return-pct 30 floor would reject every name this scan surfaces, since basers are ranging, not climbing.
The big idea: a stock that's already up 50% in 3 months is usually too extended to chase. A stock that ran up 50%, then consolidated tightly for 8-20 weeks while sellers exhausted and RS quietly improved, is a high-quality setup if the trend holds — that's what this finds. The literature backing is the William O'Neil / Mark Minervini / Stan Weinstein school: their published win rates on this exact pattern are 40-50%, which is enough to be profitable when paired with a 7-8% stop loss (asymmetric payoff).
By default each run surfaces four entry layers on every pick: (1) a composite Base Score (0-100) summarizing setup quality, (2) a Signal classification (🚀 breakout today / 🔥 imminent / ⏳ coiled / 📊 forming), (3) the pivot price to break above, and (4) an ATR-based stop loss (2.5× ATR by default). Persistence tracking via state/history.csv records each ET-date snapshot once so each subsequent run can show streak, rank changes, breakouts (left because they triggered), and breakdowns (left because they failed).
Dependencies (auto-fetched by uv run --with): Python ≥ 3.10, yfinance>=1.3,<2, pandas>=2, numpy>=1.24,<3. No persistent venv needed.
<SKILL_DIR> below is the directory containing this SKILL.md. Substitute the absolute path when running.
Run
uv run --with 'yfinance>=1.3,<2' --with 'pandas>=2' --with 'numpy>=1.24,<3' \
python <SKILL_DIR>/scripts/scan.py
... python <SKILL_DIR>/scripts/scan.py --min-base-score 60
... python <SKILL_DIR>/scripts/scan.py --min-base-weeks 10
... python <SKILL_DIR>/scripts/scan.py --min-base-weeks 4 --min-base-score 25
... python <SKILL_DIR>/scripts/scan.py --min-rs-rating 80
... python <SKILL_DIR>/scripts/scan.py --show-history
... python <SKILL_DIR>/scripts/scan.py --verbose
... python <SKILL_DIR>/scripts/scan.py --format json
... python <SKILL_DIR>/scripts/scan.py --regime-gate strict
... python <SKILL_DIR>/scripts/scan.py --ticker AAPL
... python <SKILL_DIR>/scripts/scan.py --broke-out-pct 2.0
... python <SKILL_DIR>/scripts/scan.py --recent-breakout-days 0
... python <SKILL_DIR>/scripts/scan.py --smoothness-band-pct 3.0
... python <SKILL_DIR>/scripts/scan.py --vol-collapse-ratio 0
Parameters
| Flag | Default | Notes |
|---|
--min-base-weeks | 6 | Minimum base length in weeks. Lower = catch fresh consolidations earlier with more noise. The literature floor (O'Neil "minimum 5-week flat base") is around 5-6 weeks. |
--max-base-weeks | 40 | Maximum base length. Very long bases (year+) often resolve down — momentum has bled out. |
--max-base-width | 25 | Max width % of base (high-low) / high. Bases tighter than 15% are higher quality but rarer. Loosen if too few picks; tighten for higher conviction. |
--max-to-52w-high | 15 | Max % distance from 52-week high. Closer to high = nearer to the resistance breakout. Beyond 15% means stock is in correction territory, not basing. |
--min-rs-rating | 70 | Minervini's RS Rating threshold (top 30% of universe by O'Neil-style weighted 3/6/9/12-month return). Bump to 80 for top-quintile only. |
--min-base-score | 40 | Composite Base Score floor (0-100) for display. See Output shape below for component breakdown. Bump to 60 for high-conviction only; lower to 25 in thin-cohort markets. |
--top-n | 30 | How many candidates to display + log to history. |
--min-market-cap | 5e9 | Universe market-cap floor. Lower to include small-cap setups (which are richer in this pattern but noisier). |
--min-volume | 1e6 | Universe avg-3mo-volume floor (liquidity filter). |
--universe-count | (all matches) | Universe size pulled from Yahoo's screener. Default unset = pull every match the screener reports (currently ~1000 US large caps at default mcap/volume floors). The screener returns at most 250 rows per request (Yahoo's hard cap; yf.screen raises ValueError above that), so the universe is paginated automatically in 250-row pages with offset — at default filters that's ~5 paginated requests, taking a few extra seconds, but only on cache refresh (every 7 days). Pass an explicit positive integer to cap the universe (e.g. 250 for a one-request refresh, 500 for a middle ground); 0 / negative values are rejected by argparse. If you raise --universe-count above the number of tickers already in state/universe.txt, the cache is force-refreshed even within TTL — otherwise you'd silently get the smaller cached pool. Older yfinance versions (without offset support) fall back to a single 250-row page. |
--ticker | — | Single-ticker check mode (e.g. --ticker AAPL). Bypasses the universe scan; shows which funnel stage the ticker passes/fails (Trend Template → Base detection → Score → ATR stops) with all per-stage metrics. Works for any US ticker yfinance can fetch — large-cap, small-cap, ADR, even foreign-listed — the universe is not consulted. ~2-5s vs ~30-60s for a full scan. Honors --format json for structured output. No history is written. Mutually exclusive with --show-history (if both are passed, --show-history wins and --ticker is silently ignored). |
--refresh-universe / --no-refresh-universe | (TTL 7d) | Force-refresh / use cache regardless of age. |
--show-history | — | Print history summary, no new scan. |
--clear-history | — | Wipe state/history.csv. |
--prune-non-trading-days | — | One-shot cleanup: drop history rows whose ET-date run_date is not an NYSE trading day. |
--no-save | — | Don't append this run to history (one-off exploration). |
--save-stale | — | Override the non-trading-day guard. By default the script skips append_history on weekends / NYSE holidays so streak counts don't inflate from duplicate-data days. Pre-market runs on a real trading day are still saved. |
--allow-same-day | — | [advanced/debug] Append even if a row exists for today's ET date. Default overwrites today's snapshot — the right behavior for normal use since intra-day re-runs should refresh, not duplicate. Only enable for specific debugging or forced multi-snapshot workflows. |
--format | markdown | markdown or json. |
--regime-gate | warn | off skips SPY trend + breadth calculation. warn shows the regime banner + RISK-OFF caveat but still prints top-N. strict suppresses top-N when RISK-OFF (history still saved). RISK-ON requires SPY > 200DMA and 200DMA slope over the last 20 trading days above a small -0.05% dead band. Base breakouts have higher failure rates in RISK-OFF markets — most bases break down, not up. |
--atr-stop-mult | 2.5 | ATR-based stop multiplier. Computes 14-day ATR per pick and adds a Stop@trigger column showing pivot - mult × ATR (the stop level you'd set if entering at the pivot breakout, which is the canonical entry for these setups). Typical values: 2.0 tight, 2.5 standard, 3.0 loose. Pass 0 to disable the column. (Unlike momentum-scan there's no TrailStop — trailing is for already-running positions; base setups haven't even triggered yet.) |
--no-sectors | — | Skip sector tagging. Default fetches sector/industry from yfinance for top-N picks (cached, 30-day TTL) and shows a Sector column + breakdown line. |
--vol-collapse-ratio | 0.2 | Acquisition-target / lock-in filter. A locked stock (cash buyout pending shareholder vote) looks identical to a perfect base — tight width, vol dryup, BB squeeze, RS rating high (post-gap), Trend Template passes (MAs all aligned below the gapped-up price). Without this filter, base-breakout-scan would flag every announced-but-not-closed merger as a top breakout candidate. Verified empirically: MASI on 2026-05-14 scored 88 (would be #1) but is correctly excluded by the default ratio. The check: annualized realized vol of the first half vs. second half of a fixed 3-month lookback. A locked stock has v2/v1 ≈ 0.02; a real base has both halves similar. Raise to 0.3 (hard cap 1.0) to catch more lock-ins (more false positives on calmly-drifting earnings-pop names); lower to 0.15 to require a more dramatic collapse. Pass 0 or negative to disable. Excluded names print in a dedicated section above the Top-N table with their pre/post vol ratio; excluded entries carry rank: null, pre_filter_rank, score_rank, vol_first_pct, vol_second_pct, vol_ratio. The filter has the same "gap-in-second-half" failure mode as in momentum-scan — see Known limitations. |
--persistent-min-streak | 4 | Streak threshold used by the Maturing bases section. Default 4 ≈ "survived one trading week" for daily users, or "4 weeks" for weekly runners. A maturing base is the highest-conviction signal — it means the geometry has held through actual market noise. |
--recent-breakout-days | 10 | Lookback window for the Recent breakouts section. Names that triggered the pivot on volume in the last N days (but aren't currently in the watchlist) get listed in a separate section, split by whether they're still above the pivot (working) or fell back below (failed). Set to 0 to disable the section. |
--broke-out-pct | 0.5 | Dropout-reason threshold: a dropped name with current price ≥ pivot × (1 + this/100) is labeled broke_out in the Dropouts section. Bump to 2.0 for stricter "confirmed breakout" labeling. |
--broke-down-pct | -8.0 | Dropout-reason threshold: a dropped name with current price < pivot × (1 + this/100) is labeled broke_down. Tighten to -3 for earlier breakdown flagging. |
--verbose | — | Print the funnel plus the trend-template-failure breakdown to stderr. By default only the one-line funnel prints; --verbose adds the top failure reasons (e.g. fail_ma50_gt_ma150_gt_ma200=4). Useful for understanding why a thin cohort came back. |
Output shape
A funnel-summary line (stderr), regime banner, sector breakdown, an optional Excluded by vol-collapse filter section (printed between the Regime banner and the Top-N table when the filter rejects anything — see the --vol-collapse-ratio parameter), then an optional 🚀 Breakouts today block, the main top-N table, and 2-4 discovery sections (dropouts with reasons, recent breakouts split by working/failed, new setups, maturing bases). Empty sections are skipped entirely. The Dropouts section gets a fifth reason category — Vol-collapse filtered — when a prior-run pick is excluded by the filter this run; it prints first in Dropouts (above broke_out/broke_down/deduped/faded) since it's the strongest "this is not a real signal" categorization. Sample below (illustrative — picks change daily; the exact tickers, scores, and counts will be different on your run):
Funnel: ~1000 → ~280 (RS≥70) → ~200 (TT) → ~130 (valid base) → ~50 (score≥40) → ~48 (after dedup, -1)
# Base-breakout scan — 2026-05-12 17:10 UTC
**Params**: base=6-40wks, max_width=25%, max_to_52w_high=15%, min_rs=70, min_score=40
**Universe**: ~1000 tickers · **Passed filter**: ~48 (vol-collapse: 0 excluded) · **Prior runs**: 1
**Regime**: SPY 733.3 vs 200DMA 671.6 (+9.2%) · 50DMA > 200DMA · 200DMA slope (20d): +1.48% · Breadth: 66% > 200DMA → **RISK-ON**
**Sectors**: Financial Services 9 · Energy 7 · Technology 5 · Basic Materials 4 · Communication Services 2 · Other 3
## Top 30
| # | Ticker | Sector | Score | RS | BaseWks | Width% | Smooth% | BB%ile | Vol↓ | RSslope%/wk | ToPivot% | Pivot | Sig | Stop@trigger | Streak | RankΔ | FirstSeen |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | **NEM** | Materials | 64 | 82 | 6.0 | 11.0 | 37 | 8 | 0.67 | -2.22 | -2.6 | $120.90 | 🔥 | $108.48 (-10.3%) | 2 | +1 ↗ | 2026-05-12 |
| 2 | **HSBC** | Financ | 63 | 73 | 19.0 | 17.0 | 23 | 2 | 0.70 | +0.57 | -2.8 | $92.16 | 🔥 | $86.94 (-5.7%) | 2 | -1 ↘ | 2026-05-12 |
| 3 | **PBR-A** _(also PBR, score 52)_ | Energy | 58 | 85 | 7.0 | 10.4 | 63 | 18 | 0.69 | -1.38 | -6.3 | $19.90 | ⏳ | $18.69 (-6.1%) | 2 | +2 ↗ | 2026-05-12 |
| 4 | 🔒 **TD** | Financ | 56 | 76 | 21.0 | 16.7 | 27 | 26 | 0.71 | +0.55 | -1.5 | $108.60 | 📊 | $104.68 (-3.6%) | 2 | -1 ↘ | 2026-05-12 |
...
## Dropouts since last run (3)
**Broke out** (1):
- **BHP** (was #16, pivot $84.33) (+2.9% above pivot)
**Deduped** (1, same-issuer rule):
- **PBR** (was #11; kept PBR-A instead)
**Faded out** (1):
- **AMAT** (was #14)
## Recent breakouts (last 10 trading days, 11 working / 2 failed)
**Working** (still above pivot):
- **INTC** — broke $84.99 pivot on 2026-04-29 (10d ago, 1.8× vol). Now: $116.52 (+37.1% above pivot ↗)
- **AMD** — broke $360.54 pivot on 2026-05-06 (5d ago, 2.1× vol). Now: $433.07 (+20.1% above pivot ↗)
- **PWR** — broke $637.28 pivot on 2026-04-30 (9d ago, 2.7× vol). Now: $752.77 (+18.1% above pivot ↗)
...
**Failed** (back below pivot, top 2 worst):
- **DELL** — broke $238.80 on 2026-05-08 (3d ago), now $229.03 (-4.1% below pivot ↘)
- **NOKBF** — broke $13.54 on 2026-05-11 (2d ago), now $13.00 (-4.0% below pivot ↘)
## New setups (1)
- **VLO** at #12 (score 43, base 8wks, 📊)
(Things to notice in the funnel: → 15 (score≥40) → 14 (after dedup, -1) shows the same-issuer dedup removed 1 candidate, so the watchlist is 14 not 15 — keeps the math transparent. PBR-A's row shows _(also PBR, score 52)_ because PBR is its same-issuer pair that also passed but scored lower. The Dropouts section labels PBR as Deduped rather than Faded so the user doesn't misread a structural dedup as a real price-action signal.)
(The 🚀 Breakouts today section is shown above the main table when any name fires a same-day breakout with volume confirmation. Most days the section is empty — a fresh breakout-on-volume across 250 large caps on any single trading day is genuinely uncommon. When empty, the section header is skipped entirely. The Recent breakouts section below the table catches the broader population of breakouts in the last N trading days; that one is usually populated.)
(The Maturing bases section only appears once at least one ticker has a streak ≥ --persistent-min-streak (default 4). On the first few runs of a fresh history it's correctly omitted.)
Column meanings:
- Score — composite 0-100 Base Score. Components (max points): Tightness 25 (lower width%=better, scaled 5%→25pts down to 25%→0), BB squeeze 20 (lower BB%ile=better, scaled 0pctile→20pts down to 40pctile→0), Vol dry-up 15 (0.55→15pts, 1.10→0), RS slope 20 (+2.5%/wk→20pts, -0.5%/wk→0), Pivot proximity 15 (bell curve, ideal -2% from pivot), Smoothness 10 (90%→10pts, 50%→0), Three-weeks-tight 5 bonus. Realistic top picks land 75-95; a 50-point pick is a solid setup; 70+ is high-conviction. Use as a priority filter, not a deterministic ranking — two names within 5 points are effectively tied.
- RS — O'Neil-style universe-relative RS Rating (1-99). Weighted average of trailing 3/6/9/12-month returns, percentile-ranked across the universe. ≥ 70 is the Minervini gate; ≥ 80 is the top quintile.
- BaseWks — length of the current consolidation in trading weeks. Longer bases (15+) tend to fuel bigger moves when they break, at the cost of more time waiting. The algorithm picks the trailing window that maximizes
days / max(width, 1) — so a 6-week base at 5% width can beat a 30-week base at 20% width.
- Width% —
(base_high - base_low) / base_high × 100. Tighter is better. Sub-15% is high quality; 20-25% is acceptable; capped by --max-base-width.
- Smooth% — % of base bars within ±2% of the base mean. Discriminates real horizontal consolidations (high Smooth%) from V-shapes or jagged action that happens to fit the width envelope (low Smooth%). 50%+ is meaningfully horizontal; 70%+ is textbook smooth.
- BB%ile — percentile rank of current Bollinger Band(20) width within the last 126 trading days (~6 months). 0 = tightest in 6 months (max squeeze), 100 = widest. Below 25 is meaningful compression.
- Vol↓ — volume dry-up ratio:
(last 20d avg volume) / (prior 60d avg volume). Below 1.0 = drying up (sellers exhausted, classic accumulation tell); below 0.75 = deep dry-up.
- RSslope%/wk — OLS slope of
(close / SPY) regressed over the base period, expressed as % per trading week. Positive = stock outperforming SPY while ranging (the single most important pre-breakout signal). Negative = stock losing relative strength even though price hasn't dropped much — base may be the leading edge of a downturn.
- ToPivot% — distance from current price to the pivot (the price to break above). 0 = at pivot; -3 = need a 3% move up to trigger. Negative is in-range; positive means we're already above (suspect — check the Signal column for breakout confirmation).
- Pivot — the breakout trigger price. = high of the base window. Crossing this with volume confirmation is the buy signal.
- Sig — entry-timing classifier:
- 🚀 BREAKOUT — today's close ≥ pivot AND today's volume ≥ 1.5× 20-day avg. The trigger fired today; entry decision is "now or wait for pullback".
- 🔥 IMMINENT — within 3% of pivot AND BB%ile < 25 AND vol_dryup_ratio < 0.95. The setup is fully loaded but hasn't triggered. This is the highest-information state for active traders: set a price alert at the pivot.
- ⏳ COILED — within 10% of pivot AND BB%ile < 30. Squeeze on but a few percent of work needed before the trigger.
- 📊 SETUP — valid base, but not yet near pivot or not yet showing squeeze. Watchlist candidate; check back in 1-2 weeks.
- Stop@trigger — pivot-anchored ATR stop =
pivot - 2.5 × ATR(14). The % is the distance from the pivot, not from current price. This is the stop level you'd set if you enter via a buy-stop at the pivot (the canonical entry for these setups). The JSON output also includes stop_now / stop_now_pct (current-price anchored) for users who want to size from spot today rather than wait for the breakout. The two numbers diverge by to_pivot_pct — for 🔥 names (close to pivot) they're similar; for ⏳ names farther below pivot they differ meaningfully.
- Streak — consecutive prior runs this ticker has been in the top-N (1 = first appearance). Higher = base has held through multiple periods of noise; the setup is durable.
- RankΔ — change in rank vs the latest prior appearance (positive ↗ = rising, negative ↘ = slipping, 🆕 = no prior).
- FirstSeen — earliest date this base appeared in history. Combined with Streak gives the base's age in the watchlist.
- 🔒 prefix on ticker — "three weeks tight" signal: last 3 weekly closes within 1.5% of each other. Minervini's textbook indicator that supply has been fully absorbed — institutional selling has stopped.
Discovery sections (dropouts with reasons / recent breakouts / new setups / maturing bases) are computed against the most recent prior run + the last --recent-breakout-days of price data. Sections with zero entries are skipped entirely so the output stays clean on thin days. The Maturing bases section (streak ≥ --persistent-min-streak, default 4) is correctly omitted on the first few runs of a fresh history — it only fires once a ticker has actually persisted through multiple scan-days.
Stop@trigger — worked example
For HSBC in the sample table: pivot $92.16, 14-day ATR ≈ $2.08 (computed from OHLCV). With the default --atr-stop-mult 2.5:
stop_trigger = pivot - 2.5 × ATR = 92.16 - 2.5 × 2.08 = $86.94
stop_trigger_pct = (86.94 / 92.16 - 1) × 100 = -5.7%
So if you enter via a buy-stop at $92.16 (the canonical entry: a market order triggered when price crosses the pivot), your initial stop sits at $86.94 — a 5.7% maximum loss per share if the breakout fails and the stop hits. For dollar sizing: shares = risk_per_trade ÷ (pivot − stop_trigger). If you're willing to risk $500 per trade, you'd buy ~96 shares ($500 / $5.22).
The JSON output also includes stop_now and stop_now_pct (anchored to today's close instead of the pivot) for users who want to size from spot today. The two diverge by to_pivot_pct — for 🔥 names close to pivot they're nearly identical; for ⏳ names a few % below pivot they diverge meaningfully.
Sig column markers
A trailing * after a Sig glyph (e.g. 🚀* or 📊*) means the base ended within the last 3 days and today is a fresh cross above the prior range (anchor_mode=3). Same glyph semantics — * just tells you "this base's geometry resolved very recently; the setup is hot off the press, not still building". Most days no rows have the asterisk.
Single-ticker check (--ticker AAPL)
Bypasses the universe scan and prints a 4-stage diagnostic + ATR stop levels for one ticker. Works for any US ticker yfinance can fetch (large-cap, small-cap, ADR, foreign-listed). Runtime ~2-5 seconds (vs ~30-60s for a full scan). Honors --format json for structured output. Also runs the vol-collapse check (when --vol-collapse-ratio > 0) and surfaces a prominent ⚠️ VOL-COLLAPSE WARNING block at the top if the ticker shows the acquisition-lock signature — appears even when the ticker fails earlier stages (TT-fail, no base), so a user asking "is MASI a good base?" can't accidentally miss the warning. Sample (illustrative; values will differ on your run):
# Single-ticker check: HSBC
_(using fast RS-vs-SPY proxy in place of universe-relative RS Rating)_
**RS proxy (vs SPY)**: ~76/99 (approximate)
## Stage 1: Minervini Trend Template
✅ **PASS** — all 7 criteria met
- Close: $89.49
- 50DMA: $85.99, 150DMA: $78.77, 200DMA: $75.08
- 200DMA slope (21d): +4.48%
- 52w high: $92.16 (-2.9% from current)
- ...
## Stage 2: Base detection
✅ **Valid base** detected
- Length: 19.0 weeks (95 trading days)
- Width: 17.0% ($76.52 – $92.16)
- Smoothness: 23% of bars within ±2% of mean
- Pivot price: $92.16
- ...
## Stage 3: Quality metrics
- BB(20) squeeze percentile (6mo): 2
- RS slope vs SPY during base: +0.57%/wk
- Three-weeks-tight (🔒): no
## Stage 4: Composite Base Score & Signal
- **Base Score: 62/100**
- **Signal: 🔥**
## Stage 5: Risk levels (ATR-based stops, 2.5× ATR)
- 14-day ATR: $2.08 (2.3% of price)
- **Stop @ trigger** (if entering at pivot): $86.94 (-5.7% from pivot)
- Stop @ now (if entering at current price): $84.29 (-5.8% from spot)
- For $500 max risk per trade: ~95 shares (risk-per-share = pivot − stop = $5.22)
→ **HSBC would appear in the standard watchlist.**
When the vol-collapse filter triggers, the warning prints at the top of the report — before any stage analysis — so a user can't accidentally proceed to "valid base" framing without seeing the alarm:
# Single-ticker check: MASI _(Healthcare / Medical Devices)_
_(using fast RS-vs-SPY proxy in place of universe-relative RS Rating; run the full scan if you need the exact percentile)_
> ⚠️ **VOL-COLLAPSE WARNING**: 2nd-half annualized vol = 1.9% (1st-half was 98.0%); ratio = 0.019, below the 0.20 threshold.
>
> This is the canonical signature of an acquisition target locked at a cash offer price — the chart will look like a perfect base, but the stock won't actually move.
>
> Verify via `yfinance` skill: `sec_filings --type PREM14A,DEFM14A` is the smoking gun for a pending merger. Treat any 'valid base' framing below with skepticism until verified.
**RS proxy (vs SPY)**: ~65/99 (approximate)
## Stage 1: Minervini Trend Template
❌ **FAIL** — reason: `fail_rs_rating`
...
The warning appears even when the ticker fails Stage 1 (TT-fail, no base) because the vol-collapse check runs early in the pipeline, before any short-circuit. The numbers in the warning are stated unambiguously: vol values are annualized percentages (1.9% / 98.0%); ratio and threshold are decimals (0.019 / 0.20).
The RS Rating in --ticker mode is an approximation (RS-vs-SPY proxy mapping weighted excess return through a ±30% band onto a 1-99 scale) rather than the exact universe-relative percentile — this avoids fetching the full 250-ticker universe and is the reason for the ~15× speedup. The proxy is within ~10-15 percentile points of the true rating in practice — close enough to be a TT gate, not close enough to publish as a ranked figure. For the exact RS Rating, run the full scan (without --ticker) and read the RS column.
When base detection fails but the ticker broke out in the last 10 trading days, the report includes a fallback section with the breakout date, follow-through %, and concrete action guidance ("set a price alert at $X — if price retests from above, that's the textbook O'Neil throwback entry; if it closes below for 2 sessions, the breakout failed").
How to interpret (Claude's job after running)
The script gives you data; the user wants signal. Add a short interpretation pass — apply judgment, don't recite the principles below blindly.
-
Lead with the 🚀 Breakouts section if non-empty. This is the most actionable, time-sensitive subset — a base broke today with volume confirmation. The decision space is narrow: enter now near pivot, or wait for the inevitable retest of the breakout level (usually within 5 sessions). Quantify the per-trade risk using the Stop column; reject the entry if the per-trade loss exceeds the user's risk budget. Always remind: most breakouts fail (40-60% by various studies). Stop discipline is non-negotiable.
-
🔥 IMMINENT names beat 🚀 BREAKOUTs in expected value for most users. Counterintuitively: 🚀 means the breakout already happened, so you're chasing 1-2% above the pivot with all the risk and less of the move. 🔥 means the trigger hasn't fired yet — you can set a buy-stop at the pivot, eliminating the "chase" cost. Lead with 🔥 names if any exist. Especially flag them when RS slope is also strongly positive (RSslope > +1%/wk during the base = the stock is being accumulated under the surface even as price ranges).
-
Read the Regime banner first. Base breakouts have much higher failure rates in RISK-OFF markets — most bases break down, not up, when the broader tape is weak. In RISK-OFF: do NOT recommend specific buys; reframe the list as "names showing structural strength that we want to revisit when the regime turns". The skill auto-suppresses the top-N when --regime-gate strict and RISK-OFF, which is the safer default for cautious users.
-
Watch sector clustering. A list dominated by one sector (e.g., 6 of 19 Energy, 4 Financials) often means the sector is basing, not just individual names. The trade is then the sector (sector ETF, or a basket of the top 3 from the cluster) rather than picking the highest-Score single name. Isolated newcomers in unrelated sectors are higher single-name conviction but also higher single-name risk.
-
Maturing bases (streak ≥ 4) are the real signals. Long persistence means the base has held through actual market noise — these are the highest-conviction setups by definition. A stock appearing for the first time has a thin signal (could be noise; the consolidation might break either direction). A stock with streak 6-10 has earned the watchlist slot. Combine maturing-base names with 🔥 IMMINENT status: when those overlap, that's the textbook setup.
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Read Score components for hidden information. A 60-point Score is a composite — two names with identical scores can have very different profiles. Some patterns to recognize:
- "All geometry, no RS": high tightness + BB squeeze + smoothness + pivot proximity but flat or negative RS slope. The setup looks perfect on the chart but the stock is quietly losing ground to SPY. More likely to break the wrong way.
- "All RS, no geometry": strong positive RS slope but wide width / high BB pctile / low smoothness. Stock is being accumulated but the consolidation hasn't tightened yet — typically 2-4 weeks early.
- "Balanced quality": middling on every component, no standout strength. These score 50-65 reliably across many runs and are the consistent "watchlist filler" — neither exciting nor disqualifying.
- "Loaded": high on every component including positive RS slope. Rare; usually scores 75+. These are the textbook setups.
When two picks tie on Score, prefer the one with higher RS slope — it's the most leading of the components and the one where deception (a stock geometrically tightening on the way to a downside break) is least common. Cap on the score: even all-perfect + the 3-week-tight bonus sums to 110 → capped at 100, so any 90+ is exceptional, 75+ is high-conviction, 50-65 is solid filler.
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Dropouts reveal more than the picks. A name leaving the list with reason="broke_out" is a win — the setup did what it was supposed to do. "broke_down" is a loss — the base failed and the stop (would have) fired. "no_longer_qualifies"/"faded" is neutral noise — the score drifted below threshold for benign reasons. Surface the broke_out names in particular: those validate the screening logic, and persistent "broke_out" rates above ~40% on prior watchlist picks would mean the screen is working as intended.
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The Vol↓ ratio is more leading than BB%ile. Vol dry-up usually precedes the price compression by 2-4 weeks: institutions are done selling first, then the BB tightens. A name with vol ratio = 0.60 but BB%ile = 50 may be early in the setup; same name 2 weeks later with vol 0.65 and BB%ile = 15 is the textbook "fully loaded" state. Look at multi-run trajectories using --show-history to spot this evolution.
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Read the Recent breakouts section as the bridge from "what's setting up" to "what just broke". The main watchlist surfaces pre-breakout candidates; Recent breakouts surfaces names that crossed their pivot on volume in the last 5-10 trading days — too late to enter at the pivot but still in the follow-through window. Use the split:
- Working (positive % vs pivot): the breakout is confirmed — these names crossed and held. The actionable read is whether a pullback to the breakout level offers a second entry (textbook O'Neil "throwback" entry). When a working breakout is +1-5% above pivot, that retest is often imminent; when it's +15%+ above pivot, the entry window is closed and chasing is high-risk.
- Failed (negative % vs pivot): the breakout triggered then reversed — the base failed. These are also informative as a tape signal: when the failed list is unusually long (more failed than working), it means the broader market is digesting breakouts poorly — a yellow card on initiating new entries in the main watchlist until the ratio flips.
- When the section is missing (or has zero entries), no qualifying breakouts happened in the lookback window — quiet stretch, focus shifts to the main watchlist alone.
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Never recommend specific buys. Frame results as "names worth investigating" with specific risk parameters (pivot for entry, ATR stop for risk). Always flag: base-and-breakout strategies depend on stop discipline more than entry selection. The literature win rate is 40-50%; without the stop loss, that's a money-losing strategy. With a 7-8% (or ATR-based) stop and asymmetric payoffs, it's profitable. The skill cannot enforce the stop; only the user can.
State files
state/history.csv — one snapshot per US market day (America/New_York) × every top-N ticker. Columns: run_id, run_date, ticker, rank, base_score, base_weeks, width_pct, bb_pctile, vol_dryup_ratio, rs_slope_pct_per_wk, to_pivot_pct, pivot_price, signal. (The anchor_mode field is computed but not persisted to history — it's only relevant for the current scan's Sig column markers.) Re-running the same ET day overwrites that day's rows. Writes are atomic (.tmp + rename) so a crash mid-write can't truncate. The skill gets more useful with each subsequent run — first run is just the picks; later runs add streak, RankΔ, breakout/breakdown tracking, and base-maturation signal.state/universe.txt — cached universe list, auto-refreshed every 7 days via Yahoo's screener.state/sectors.json — per-ticker {sector, industry, ts} cache. 30-day TTL per ticker. Fetched lazily on top-N picks only.
Storage growth: at default --top-n 30, each run adds ~30 rows × ~150 bytes ≈ 4.5 KB. A year of daily runs ≈ 1.6 MB; weekly ≈ 230 KB. Negligible for years of typical use.
Cadence
Cadence-agnostic by design. One snapshot per US market day (America/New_York), so streak counts consecutive prior scan-days — running multiple times on the same ET day refreshes that day's entry. Runs on weekends or NYSE holidays auto-skip from history (results still print, just nothing is appended) so streak doesn't inflate from duplicate-data days. Pre-market runs on a real trading day do save.
Recommended cadence:
- Daily: streak unit is days. Finest granularity, sees breakouts the day they happen. Best for active traders.
- Weekly (Friday close): streak unit is weeks. Recommended sweet spot — captures base maturation 4× faster than monthly while smoothing intra-week noise. Best for swing traders.
- Monthly: streak unit is months. Smoothest signal, only the longest / highest-conviction bases survive. Best for position traders.
For automatic recurring runs, use a local scheduler (macOS launchd, or cron) pointing at scripts/scan.py. The schedule skill runs remote agents in Anthropic-managed sandboxes that can't see this local state/ directory.
Known limitations
- Base-detection is a screener heuristic, not a chart annotator. The trailing-window approach (find the longest window where price range ≤ max_base_width) catches the same population as Minervini's VCP / O'Neil's cup-and-handle without trying to identify those exact patterns. Real chartists can find textbook bases this misses (e.g., a stair-stepping handle inside a larger cup), and vice versa — a window that meets the numerical criteria may be a failing base by eye (e.g., descending highs, no proper handle). Use the surfaced names as candidates to chart, not as finished analysis.
- Survivorship bias — the universe is current US large caps; delisted names are absent. This is fine for forward-looking screening but means any backtested win rate from this exact universe would be optimistic vs. a true point-in-time universe.
- Yahoo data quirks — rare missing bars, late dividend adjustments. If a single name's metrics look wrong (e.g., width% way off the chart), sanity-check via the
yfinance skill or the underlying ticker's chart on any free site.
- 52w high reference is rolling, not the absolute high. A stock that made an all-time high 14 months ago doesn't show that high — we only see the last 252 trading days. So a "20% from 52w high" might be a much smaller correction from a more-recent acute high vs. all-time. Usually doesn't matter for the screen's purpose (we're looking at recent setups), but worth knowing when interpreting deep-base names.
- RS Rating is universe-relative, not market-relative. O'Neil's published RS Rating uses a much broader universe (~6000 stocks); ours uses the 250 large caps in scope. So our RS = 70 corresponds to "top 30% within S&P large caps", not "top 30% across all listed stocks". For large-cap-only investing this is the right denominator; for "is this stock outperforming the market as a whole", check RS slope (which uses SPY).
- Base detection ignores patterns within the base. A stock ranging 0-25% width passes width check whether the range is smoothly horizontal or jagged with V-spikes. The latter often looks "right" by the screen but fails more often in practice. Cross-checking with the BB%ile (low BB pctile = smooth) and width% (low width = smooth) filters out most of the V-spike cases, but not all.
--regime-gate reduces bear-market downside but can't catch fast regime flips. A 200DMA slope that turns negative requires ~20 trading days to register; a 1-week crash (Aug 2024, March 2020, Feb 2018) blows through the gate before the slope flips. Treat the regime banner as helpful framing, not a defensive moat.- Volume dry-up ratio uses 20d/60d SMA, which lags. Fast regime changes (M&A talk, earnings surprises) spike volume in days; our ratio takes weeks to fully reflect. Treat the metric as "is supply slowly drying up" rather than "what's volume doing today".
- The "broke_out" / "broke_down" labels in dropouts use a simple 0.5% / 8% threshold from the pivot. A name that broke out by 0.3% and reversed isn't a confirmed breakout — but we'd label it "no_longer_qualifies" only if it's below the threshold today. Treat the dropout reasons as a heuristic, not as an audit trail.
- Vol-collapse filter has a "gap-in-second-half" blind spot.
--vol-collapse-ratio compares the realized vol of two halves of a fixed 3-month lookback. It catches lock-ins when the announcement gap falls in the first half (typical case: gap happened 1-3 months ago). When the gap day lands in the second half (announcement was within the last ~6 weeks), the gap inflates v2 above v1, ratio > 1, name passes through. Failure mode is late detection, not silent miss: by a few weeks later the gap drifts into the first half and the filter catches it. The 5%-annualized minimum first-half vol guard prevents already-low-vol names from being flagged on noise. False-positive direction: names that gapped on an earnings beat and then drifted calmly higher with very orderly daily ranges can compress 2nd-half vol enough to trip the filter; lower --vol-collapse-ratio to 0.15 to reduce these. The filter doesn't catch tender-offer situations that don't involve a single-day gap (slow accumulation of shares at small premiums) — those produce a normal-looking price chart with no anomaly to detect. Identification heuristic for a leak: any base with MaxDD% improbably small (< -1%) and width% < 2% is suspect. Cross-check with yfinance skill: sec_filings --type PREM14A,DEFM14A is the smoking gun (proxy filings relating to a merger); 8-K / DEFA14A is suggestive but not conclusive.
- Single-ticker mode (
--ticker MASI) has the same gap-in-second-half blind spot, with worse practical impact. Asking the scanner "is MASI a good base?" on the day a merger is announced will pass through without the warning — the gap is at the end of the window, inflates v2, ratio > 1, no trigger. The universe scan is forgiving (many tickers, signal redundancy) but single-ticker mode answers a high-stakes "should I trade this name today?" question. By the time the gap drifts into the first half (~2-3 weeks later) the warning fires, but day-1 false positive is the worst failure mode. There's no clean fix using only the split-half geometry — a complementary "did the most recent N days have a single move > 20%?" check would catch announcement-day gaps, but adds a separate detection pattern. For now, when running --ticker on any recently-gapping name (visible from a quick history chart check), manually verify via sec_filings --type PREM14A,DEFM14A before treating it as a tradeable base.
- No fundamental check. The screen is 100% price/volume; it doesn't know if the company has decelerating earnings, regulatory overhang, or executive turnover during the base. The literature's 40-50% win rate is without a fundamental filter — adding even a simple "EPS growth not declining" check would lift it materially. The user should at minimum eyeball the latest earnings before acting on any pick.
- Pivot is the in-base high, which may be conservative. Some chart traders prefer the high of the handle (a sub-pattern inside a cup-with-handle base) as the actual pivot, which is typically a few percent below the full cup high. Our pivot uses the full base high — slightly more conservative trigger, slightly worse entries, slightly lower false-breakout rate.
- Universe pagination has a hard stop at
SCREENER_MAX_PAGES (20 pages = ~5000 tickers) — this only matters if Yahoo's response stops including the total field (schema drift), in which case the script falls back to per-page heuristics (short page / zero new tickers) to detect end-of-results. The 20-page cap is the absolute backstop; if it ever triggers you'll see refresh_universe: hit SCREENER_MAX_PAGES=20 backstop on stderr and the universe will be capped at ~5000 — well above any realistic large-cap match count, so triggering it is a strong signal something is wrong upstream.
- Universe size affects historical rank comparability — if you raise
--universe-count (or the underlying universe grows from market-cap drift) between runs, ranks recorded in state/history.csv from before the change aren't directly comparable to ranks after. A larger universe means more names can pass the funnel, which can demote previously-high-ranked names not because their setups weakened but because new entrants were added to the pool. Streak and FirstSeen survive (a ticker is still "in the top N" or not), but RankΔ across a universe-size change should be read with that caveat. If you want clean before/after comparison, run --clear-history after changing universe size.
