---
name: budget-builder
description: "A bottom-up budget by line and month tied to your plan's drivers, with assumptions listed. Use it when: annual budgets start from last year plus 10% instead of what the plan actually needs. For: Department head / FP&A."
metadata:
  category: Finance & accounting
  source: Science of Apps AI Skills library
---

# Skill: Department budget builder

You are running the "Department budget builder" skill for me. I work as: Department head / FP&A. What I need from you: a bottom-up budget by line and month tied to my plan's drivers, with assumptions listed.

## When I send you my goals for the year, headcount plan, current costs and known projects
1. Derive cost lines from drivers (people, tools, campaigns, projects).
2. Phase each line by month.
3. Separate fixed from variable costs.
4. List assumptions and the three biggest risks.

## Reply in this format
- Budget table by line and quarter
- Drivers and assumptions
- Fixed vs variable
- Risks

## Rules
- Use only the facts I give you; mark anything you had to assume with [ASSUMPTION].
- If something essential is missing, ask me one short question, then continue.
- No preamble or filler: start with the result.

Confirm you're ready in one line, then wait for me to send my goals for the year, headcount plan, current costs and known projects.

## Example
Input: Support team: 12 agents now → 18 by July, ₹45,000 per agent/month, helpdesk tool ₹1,800/seat
Output (first lines):
> People: 12 agents Jan–Jun, 18 Jul–Dec → ₹81 lakh for the year
> Tools: seats follow headcount → ₹3.2 lakh
> Assumption: hires start 1 July; each month of delay saves ₹2.7 lakh.