Guide · Agent skill
How to use the Sales Forecast Workbook agent skill
Updated · written with AI from the project's own documentation and checked against our catalogue data
The sales-forecast skill is an agent skill that takes your historical sales numbers and produces a forecast as an Excel workbook. It separates the history into trend and seasonal patterns, then adds confidence bands, three scenarios, a sensitivity table and a notes sheet that explains the method and its limits. This guide covers what the skill does, how to install it, how to ask for a forecast, and what to check before you rely on the results.
Sales Forecast Workbookgenspark-ai/genoffice · Apache-2.0 Download the skill Quick start
- 1Download the ZIP. Get the sales-forecast skill ZIP from the page where you found this guide.
- 2Install the skill. Unzip it into ~/.claude/skills/ for personal use or into .claude/skills/ in a project, or upload the ZIP under Settings → Capabilities → Skills in the Claude apps.
- 3Prepare your sales data. Gather at least 24 months of monthly sales if you want seasonal results, and note the basis (units or revenue, tax, returns).
- 4Ask in plain language. Request a forecast, for example by asking for next year from two years of monthly sales, and list any known future events.
- 5Answer the agent's questions. Confirm the horizon, granularity, basis and how to treat anomalies, since the choice to exclude or keep them is yours.
- 6Review the workbook. Check the Assumptions and Notes sheets, change any parameters, and confirm the forecast updates before using it.
What does the sales-forecast skill make the agent do?
When the skill is active, the agent treats your sales history as a time series. It splits the series into a trend, a seasonal factor and a residual, then forecasts future periods as trend multiplied by seasonal factor. You can then overlay known future events such as a promotion or price change.
The forecast is built with spreadsheet formulas, such as FORECAST.LINEAR, TREND and AVERAGE. If you change the history or an assumption in the workbook, the results update, so you can see how each input affects the outcome.
How do you install the sales-forecast skill?
Download the skill ZIP from the page where you found this guide. Then choose one of two routes.
For a personal install, unzip the file into your ~/.claude/skills/ folder. For a project-only install, unzip it into the .claude/skills/ folder inside your project. Alternatively, upload the ZIP in the Claude apps under Settings → Capabilities → Skills.
- Personal: unzip into ~/.claude/skills/
- Project: unzip into .claude/skills/ inside the project folder
- Claude apps: Settings → Capabilities → Skills, then upload the ZIP
~/.claude/skills/Check your data before you ask for a forecast
Seasonal forecasting needs at least two full seasonal cycles. For monthly data that means 24 months. With less history, the skill does a trend-only forecast and says so explicitly. Treat a trend-only result as weak evidence.
You will also be asked about the forecast horizon, the granularity (day, week or month), whether the figures are units or revenue, whether they include tax and returns, and any known future changes such as new products, promotions, price increases or channel changes. Having these answers ready speeds things up.
- At least 24 months of monthly sales for seasonal forecasting
- Clear basis: units or revenue, tax-inclusive or not, returns included or not
- List of known future events and their expected impact
How do you trigger the skill with a natural request?
You do not need a special command. Describe what you want in plain language and paste or attach your sales data. The skill is designed for requests like the two quick prompts below.
If you want per-product or per-region forecasts, say so in the request. The skill forecasts each group separately and then aggregates them, and it explains on the Notes sheet any material difference from a direct total forecast.
- Forecast next year from these two years of monthly sales
- Give this forecast optimistic, base and pessimistic scenarios
What is in the Excel workbook you receive?
The output is one workbook with five sheets. History holds the cleaned series with an anomaly flag column. Assumptions lists every adjustable parameter with its value, basis and the scenarios it affects. Forecast shows period, actual, trend, seasonal factor, base forecast, bounds and scenarios, with a line chart that draws history and forecast in different line styles.
Sensitivity shows how each key assumption changes the full-year total when moved by plus or minus 10 percent. Notes records the method, data range, exclusions, limitations and how to update the model.
- History: cleaned data and anomaly flags
- Assumptions: adjustable parameters you can change
- Forecast: base, lower and upper bounds, optimistic and pessimistic lines, chart
- Sensitivity: effect of each assumption on the full-year total
- Notes: method, exclusions, limitations, update steps
What are the safety notes and limits?
This skill does not run scripts and does not use the network. It needs spreadsheet tools that the agent can use to create an Excel workbook, and it needs the historical sales data you supply.
The confidence bands are statistical intervals based on the variation in past residuals. They are not guarantees. A forecast is not a target. If you need a sales target, set it separately, because the skill itself states this distinction.
- No scripts are run by this skill
- No network use
- Bands are statistical intervals, not commitments
- Anomalies such as promotion spikes or stock-outs: you decide whether to exclude or keep them
What people use it for
- Planning next year's monthly unit sales for a small business with two years of history
- Comparing optimistic, base and pessimistic scenarios for a budget discussion
- Testing how sensitive the full-year total is to growth or seasonal strength assumptions
- Producing a documented first-pass forecast that a finance reviewer can audit cell by cell
Frequently asked questions
How do I install the sales-forecast agent skill?
Download the skill ZIP from the page, then unzip it into ~/.claude/skills/ for personal use or into .claude/skills/ inside a project. You can also upload the ZIP in the Claude apps under Settings → Capabilities → Skills.
Is the sales-forecast skill free to use?
The skill is published under the Apache-2.0 licence. Check that licence for the terms of use and redistribution, as this guide does not add any pricing or licence conditions.
What do I need to run the sales-forecast skill?
You need spreadsheet tools available to the agent so it can create an Excel workbook, plus historical sales data from you. For seasonal forecasts, at least two full seasonal cycles are needed, which is 24 months for monthly data.
Does the skill run scripts or use the internet?
No. The skill runs no scripts and uses no network. It works from the data you provide and the spreadsheet tools available to the agent.
Why does the forecast show only a trend when I have less than two years of data?
Seasonal patterns cannot be estimated reliably from less than two full cycles. The skill then produces a trend-only forecast and states this explicitly, and the result should be treated as weak evidence.
Can I use the forecast as a sales target?
The skill itself says a forecast is not a target and its bands are statistical intervals, not guarantees. Set targets separately, using the forecast as one input.
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Our verdict
Use this skill if you are a sales or finance person, or a small business with at least two years of monthly sales, who wants a first-pass forecast in Excel with formulas you can inspect. Pick something else if your history is very short or noisy, or if you need a sales target or commitment, since the skill is explicitly designed not to produce those.
Download the skill