downtrend-duration-analyzer

downtrend-duration-analyzer is a skill for Claude Code from mphinance/alpha-skills. It costs 27 tokens per session (1,405 once invoked), scanned A, a copy of downtrend-duration-analyzer, MIT.

A historical stock-price analyzer that measures how long downtrends last from a peak to a later low. It creates interactive HTML histograms grouped by industry sector and company size.

In plain words
What is it for?
Comparing correction durations, estimating holding periods, and setting time limits for strategies that expect prices to recover.
Why use it?
It provides evidence for how long corrections have typically lasted, helping avoid unrealistic recovery expectations.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: positional $N argument.

Part of the quant-skills plugin — 20 skills shipped together

Good fit Comparing correction durations, estimating holding periods, and setting time limits for strategies that expect prices to recover.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/mphinance/alpha-skills/downtrend-duration-analyzer
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add mphinance/alpha-skills --skill downtrend-duration-analyzer
Clone the repo
git clone --depth 1 https://github.com/mphinance/alpha-skills

Made for: Claude Code.

Or install quant-skills, the plugin that ships this one along with the rest of its 20 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for downtrend-duration-analyzer

README.md
[![agentmods](https://agentmods.dev/badge/skills/mphinance/alpha-skills/downtrend-duration-analyzer/github.svg)](https://agentmods.dev/skills/mphinance/alpha-skills/downtrend-duration-analyzer)
Your own site
<a href="https://agentmods.dev/skills/mphinance/alpha-skills/downtrend-duration-analyzer"><img src="https://agentmods.dev/badge/skills/mphinance/alpha-skills/downtrend-duration-analyzer/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for downtrend-duration-analyzer

Your own site · 80×15
<a href="https://agentmods.dev/skills/mphinance/alpha-skills/downtrend-duration-analyzer"><img src="https://agentmods.dev/badge/skills/mphinance/alpha-skills/downtrend-duration-analyzer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 27 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,405 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 100% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00027 $0.01405
Opus 5 $0.00014 $0.00702
Sonnet 5 $0.00005 $0.00281
Haiku 4.5 $0.00003 $0.00140

Measured 10d ago against content hash 9d9e0610ad57, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

downtrend-duration-analyzer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.

The scan reads SKILL.md. This mod also ships 5 executable files (scripts/analyze_downtrends.py, scripts/generate_histogram_html.py, scripts/tests/conftest.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

100% identical to downtrend-duration-analyzer — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/quant-skills/skills/downtrend-duration-analyzer/SKILL.md · 177 lines

How it starts

The opening of the file, as written. The whole thing — 177 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Downtrend Duration Analyzer

Overview

Analyze historical price data to identify downtrend periods (peak-to-trough) and build statistical distributions of correction durations. Generate interactive HTML visualizations with histograms segmented by sector and market cap to help traders understand typical recovery timeframes and set realistic expectations for mean reversion strategies.

When to Use

  • Trader asks about typical correction lengths for a sector or market cap tier
  • User wants to understand historical drawdown recovery times
  • Building mean reversion or pullback strategies that need realistic holding period estimates
  • Comparing correction behavior across different market segments
  • Setting stop-loss timeouts or position holding period limits

Prerequisites

  • Python 3.9+
  • FMP API key (set FMP_API_KEY environment variable or use --api-key)
  • Required packages: requests, pandas, numpy (standard data analysis stack)

Workflow

Step 1: Fetch Historical Price Data

Run the analysis script to fetch OHLC data for a universe of stocks and identify downtrend periods.

python3 skills/downtrend-duration-analyzer/scripts/analyze_downtrends.py \
  --sector "Technology" \
  --lookback-years 5 \
  --output-dir reports/

Step 2: Analyze Downtrend Durations

The script automatically:

  1. Identifies local peaks and troughs using rolling window analysis
  2. Calculates duration (trading days) and depth (% decline) for each downtrend
  3. Segments results by sector and market cap tier (Mega, Large, Mid, Small)
  4. Computes summary statistics (median, mean, percentiles)

Step 3: Generate Interactive HTML Visualization

python3 skills/downtrend-duration-analyzer/scripts/generate_histogram_html.py \
  --input reports/downtrend_analysis_*.json \
  --output-dir reports/

This creates an interactive HTML file with:

  • Histogram of downtrend durations
  • Filters for sector and market cap
  • Hover tooltips with percentile information
  • Summary statistics table

Read the full file on GitHub · 177 lines

Files

What ships with it

7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 10d ago First seen · 177 lines · 27 tokens per session scan A 9d9e0610ad57

Subscribe to this mod's changes

downtrend-duration-analyzer is a skill published in the GitHub repository mphinance/alpha-skills (21 stars, last pushed 12d ago), licensed MIT. It adds 27 tokens to every session and 1,405 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to downtrend-duration-analyzer, differing in 0 lines, and is treated as a copy.

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