forecasting
BusinessHow to produce a demand forecast for a SKU, and when to delegate that to a subagent vs. compute it yourself. Load this for any task involving "forecast", "how much will we sell", "next month", promos, or seasonal SKUs.
How to use this skill
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Demand Forecasting
Forecasting has two paths. Pick the right one — using a subagent when you don't need one wastes turns; skipping it when you do gives you a bad number.
Path A — compute it yourself (code execution)
Use this when all of the following hold:
- horizon ≤ 14 days
- the product's
is_seasonalflag is 0 - the product's
promo_next_monthflag is 0 - the task doesn't mention a promo, holiday, or trend change
Then the forecast is just a rolling mean. This skill ships a script for it:
python .claude/skills/forecasting/rolling_mean.py SKU-0057 14
That's it — one Bash call, ~200 tokens, no subagent. Read the script if you want to adapt it (it's ~20 lines).
Batch variant for sweeps: if you need days-of-cover for many SKUs at once (e.g., the daily low-stock check), don't loop tool calls — run the batch script:
python .claude/skills/forecasting/batch_days_of_cover.py 20
Returns the 20 most urgent SKUs as JSON, ranked by days-of-cover. This is
what replaces the 100+ get_stock_level / get_sales_velocity calls the
old agent made on F1.
Path B — spawn a forecaster subagent
Use this when any of the following hold:
- horizon > 14 days
is_seasonalis 1promo_next_monthis 1, or the task mentions a promo- recent sales show a visible trend break
Why a subagent: the forecaster needs the full 90-day history in context to spot seasonality and promo effects. That's ~90 rows × however many SKUs. Loading that into your context crowds out the rest of the task. A subagent gets its own context window, does the analysis there, and hands back a small JSON.
How: Delegate to the forecaster callable agent. Send it just the SKU,
product flags, and horizon — not the history rows. The forecaster has
Bash access to the same /mnt/user/data/ and will compute over the full
history in its own context (that's the point: the 90 rows live there, not
here). It returns {forecast_qty, confidence, method, flags} JSON —
parse it strictly; if the JSON is malformed that's an error, not
something to guess around.
If callable_agents isn't available (it's a research-preview feature),
fall back to computing the rolling-mean inline yourself and set
confidence ≤ 0.55 so the reorder-policy skill escalates to human review
instead of auto-ordering on a number you couldn't validate.
Seasonal calendar (sanity-check your numbers)
Outdoor gear is highly seasonal. When the horizon crosses a boundary, the rolling mean lags the turn — lean on Path B and mention the season.
| Window | Categories that lift | Expect vs baseline |
|---|---|---|
| Mar–May | Footwear, packs, rain shells, trekking poles | 1.3–1.6× |
| Jun–Aug | Tents, sleeping, stoves, water filtration | 1.5–2.0× (peak quarter) |
| Sep–Oct | Insulated apparel, optics, headlamps | lift; tents/footwear taper |
| Nov–Dec | Giftable price points; heaviest promo | confirm promo flags |
| Jan–Feb | Reset — lowest volume | good for cycle counts |
Promotional handling
Promos are the most common cause of under-ordering. When promo_next_month=1
or the task mentions a promo:
- Do not rely on rolling-mean alone — that's pre-promo demand.
- Look for a historical analog (same SKU, comparable promo in the last 12
months) and use that uplift. If none exists, the subagent should set
flags: ["promo_uplift_uncertain"]and a confidence well under 0.6. - Default to flag-for-review over auto-order when lift is uncertain. Over-ordering on a promo is recoverable; under-ordering is a stockout during peak attention.
- If the promo end date is known, account for the post-promo dip — don't leave the channel overstocked the week after.
The failure mode to avoid: stating the lift in prose ("could be ~3×")
while the forecast_qty you return is still the un-lifted baseline mean.
Anchor the number, not just the narrative.
What to do with the result
Feed {forecast_qty, confidence, flags} into the reorder-policy skill. In particular: if confidence < 0.6, reorder-policy says escalate, don't auto-order. Do not drop the confidence or flags on the floor — they're part of the contract.
Worked example (Path B)
Task: "Reorder SKU-0091 for next month's promo." → promo_next_month=1, horizon=30 → Path B.
Subagent returns: {"forecast_qty": 2100, "confidence": 0.41, "method": "baseline_mean_no_comparable_promo", "flags": ["promo_uplift_uncertain"]}
confidence 0.41 < 0.6 → per reorder-policy, do not create a PO. Escalate via notify-templates with the flags, recommend ~2,100 baseline + note that promo uplift could be 2-3× and needs a human call.