---
name: demand-signal-analyzer
description: "Analyzes demand history alongside market signals and external data to decompose seasonality, trend, and anomalies, then produces a demand signal interpretation with confidence levels, a baseline vs. adjusted demand view, and prioritized planning actions. Use when interpreting demand patterns, diagnosing forecast misses, sensing near-term demand shifts, or preparing a demand review for S&OP."
argument-hint: "[product-or-category] [demand-history]"
allowed-tools: ["Read"]
---

# Demand Signal Analyzer

## Purpose
Turn raw demand history and scattered market signals into a clear, defensible interpretation of what demand is actually doing — separating seasonality, underlying trend, and one-off anomalies — and delivering an adjusted demand view with explicit confidence levels so planners know how much to trust each signal before committing to a forecast.

## When to Use
Invoke this skill when the user asks to:
- Interpret demand patterns or decompose a product's demand history
- Diagnose why a forecast missed and whether it was a signal or noise
- Identify seasonality, trend shifts, or anomalies in a SKU or category
- Sense near-term demand changes from promotions, pricing, or market events
- Prepare a demand signal summary for an S&OP or demand review meeting
- Reconcile statistical patterns with qualitative field or sales intelligence

## Inputs Required
Before starting, collect:
- **Product or category scope**: The SKU, product family, or category being analyzed
- **Demand history**: Historical demand by period (weekly or monthly), ideally 18–36 months — shipments, orders, or POS/sell-through (note which)
- **History granularity and horizon**: Time bucket used and how far forward the interpretation must serve
- **Market signals**: Any known qualitative or leading indicators — promotions, price changes, competitor moves, new listings, macro trends, weather, campaigns
- **External data inputs**: Any available external series (category demand, search trends, economic indicators, channel data)
- **Known events**: Stockouts, one-time bulk orders, data errors, channel shifts, or supply disruptions that distort history
- **Planning objective**: What decision this feeds — forecast override, safety stock, buy quantity, or executive review

If granularity or horizon is missing, default to monthly buckets and a 6-month forward interpretation, and state the assumption.

## Instructions

### Step 1: Data Integrity Check
Before interpreting anything, validate the history is usable.
- Flag periods affected by **stockouts** (censored demand — actual demand exceeded what shipped)
- Flag **one-time distortions**: bulk orders, channel loads, returns, data errors, duplicate entries
- Note **structural breaks**: new product introductions, discontinuations, channel or customer additions, list price resets
- State whether the series measures **true demand** (orders/POS) or **constrained supply** (shipments) — this changes everything downstream
- Recommend cleansing actions (e.g., "impute stockout months to trend + seasonality") before decomposition

### Step 2: Time-Series Decomposition
Separate the signal into its components.
- **Level (baseline)**: The de-seasonalized, de-trended average demand
- **Trend**: Direction and slope — flat, growing, declining, or inflecting. Quantify (e.g., "+3% per month over trailing 6 months" or "trend reversal from +2% to −4% around period X")
- **Seasonality**: Identify recurring patterns and estimate seasonal indices per period (e.g., "December runs 1.6x baseline; February 0.7x"). Distinguish true seasonality (repeats across ≥2 cycles) from a one-time spike
- **Residual/noise**: What's left after level, trend, and seasonality — high residual variance means low predictability
- State the decomposition method assumption (additive vs. multiplicative) and why

### Step 3: Anomaly Identification
Isolate points that don't fit the pattern.
- Classify each anomaly as: **promotional lift**, **demand shock** (external event), **data artifact**, **supply-constrained (censored)**, or **unexplained**
- For each, estimate magnitude (% or units above/below expected) and whether it is **repeating** (a new pattern forming) or **isolated** (noise to exclude)
- Distinguish anomalies to **remove from baseline** vs. anomalies that **signal a real shift** and should be carried forward

### Step 4: Qualitative Signal Integration (Demand Sensing)
Reconcile the statistics with market intelligence.
- Map each provided market signal to an expected demand effect: **direction** (up/down), **magnitude** (small/moderate/large), and **timing** (immediate/lagged/lead)
- Identify **corroboration** (qualitative signal confirms the statistical pattern → higher confidence) vs. **conflict** (field says growth, history says decline → flag for investigation)
- Weight leading indicators (search trends, competitor exits, pipeline) that the historical series cannot yet reflect

### Step 5: Confidence Scoring
Assign an explicit confidence level to the overall interpretation and to each key signal.
- Use a **High / Medium / Low** scale with stated drivers:
  - **High**: ≥2 full seasonal cycles, low residual variance, corroborating qualitative signals, clean data
  - **Medium**: Partial history, moderate noise, or mixed qualitative signals
  - **Low**: Short/dirty history, high residual variance, conflicting signals, or a structural break in progress
- Never present an interpretation without its confidence level and the top 2 reasons behind it

### Step 6: Baseline vs. Adjusted Demand View
Produce the actionable output.
- **Baseline**: Statistical expectation from level + trend + seasonality, with anomalies removed
- **Adjusted**: Baseline modified for validated qualitative signals and forward events, with each adjustment itemized and justified
- Present as a period-by-period view (table) so the planner sees exactly where and why the adjusted view diverges from baseline

### Step 7: Prioritized Planning Actions
Translate interpretation into decisions.
- List 4–6 actions ranked by impact and urgency (e.g., "raise Q4 forecast +12% for peak seasonality — High confidence"; "investigate conflicting field signal on SKU-X before overriding — Medium")
- Flag any signal needing more data before action, and specify exactly what data would resolve it

## Output Format
- **Structure**: Seven sections following the analysis sequence; decomposition and baseline vs. adjusted views presented as tables; actions as a ranked list
- **Length**: 900–1,300 words
- **Format**: Structured document with tables for seasonal indices and the baseline-vs-adjusted period view; bullets and short prose elsewhere
- **Sections**: Data Integrity Check → Decomposition (level/trend/seasonality/residual) → Anomaly Identification → Qualitative Signal Integration → Confidence Scoring → Baseline vs. Adjusted Demand View → Prioritized Planning Actions
- **Tone**: Demand planning specialist — quantitative, cautious about noise, explicit about uncertainty, decision-oriented

## Quality Checklist
Before delivering output, verify:
- [ ] Data integrity issues (stockouts, one-time orders, structural breaks) are flagged before any interpretation
- [ ] Seasonality is quantified with per-period indices, not described vaguely as "seasonal"
- [ ] Every anomaly is classified (promo / shock / artifact / censored / unexplained) and marked as isolated or repeating
- [ ] Each key signal and the overall interpretation carry an explicit High/Medium/Low confidence level with stated drivers
- [ ] Baseline vs. adjusted view is shown period-by-period with each adjustment itemized and justified
- [ ] Planning actions are ranked by impact and each carries its confidence level

## Notes
- Shipments are not demand — if the series is constrained supply, say so and treat stockout periods as censored, or the trend will be understated
- Two full seasonal cycles is the practical minimum for trustworthy seasonal indices; with less, downgrade confidence and lean on category or analog data
- A conflict between statistical history and field intelligence is a finding, not a problem to smooth over — surface it and specify what would resolve it
- When history is short or noisy, a Medium-confidence adjusted view with a clear investigation action beats a falsely precise number

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## How to use this skill

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**Using in Claude.ai, ChatGPT, Gemini, or other AI tools:**

1. Drag this file into a new chat, or copy and paste its contents
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