wind-alice/dcf-model

DCF Model Builder

Overview

This skill creates institutional-quality DCF models for equity valuation following investment banking standards. Each analysis produces a detailed Excel model (with sensitivity analysis included at the bottom of the DCF sheet).

Tools

• Default to using all of the information provided by the user and MCP servers available for data sourcing.

Critical Constraints - Read These First

These constraints apply throughout all DCF model building. Review before starting:

Environment: Office JS vs Python/openpyxl:

• If running inside Excel (Office Add-in / Office JS environment): Use Office JS directly — do NOT use Python/openpyxl. Write formulas via range.formulas = [["=D19*(1+$B$8)"]]. No separate recalc step needed; Excel calculates natively. Use range.format.* for styling. The same formulas-over-hardcodes rule applies: set .formulas, never .values for derived cells.
• If generating a standalone .xlsx file (no live Excel session): Use Python/openpyxl as described below, then run recalc.py before delivery.
• The rest of this skill uses openpyxl examples — translate to Office JS API calls when in that environment, but all principles (formula strings, cell comments, section checkpoints, sensitivity table loops) apply identically.

⚠️ Office JS merged cell pitfall: When building section headers with merged cells, do NOT call .merge() then set .values on the merged range — Office JS still reports the range's original dimensions and will throw InvalidArgument: The number of rows or columns in the input array doesn't match the size or dimensions of the range. Instead, write the value to the top-left cell alone, then merge and format the full range:

// WRONG — throws InvalidArgument:
const hdr = ws.getRange("A7:H7");
hdr.merge();
hdr.values = [["MARKET DATA & KEY INPUTS"]];  // 1×1 array vs 1×8 range → fails

// CORRECT — value first on single cell, then merge + format the range:
ws.getRange("A7").values = [["MARKET DATA & KEY INPUTS"]];
const hdr = ws.getRange("A7:H7");
hdr.merge();
hdr.format.fill.color = "#1F4E79";
hdr.format.font.bold = true;
hdr.format.font.color = "#FFFFFF";

This applies to every merged section header in the DCF (market data, scenario blocks, cash flow projection, terminal value, valuation summary, sensitivity tables).

Formulas Over Hardcodes (NON-NEGOTIABLE):

• Every projection, margin, discount factor, PV, and sensitivity cell MUST be a live Excel formula — never a value computed in Python and written as a number
• When using openpyxl: ws["D20"] = "=D19*(1+$B$8)" is correct; ws["D20"] = calculated_revenue is WRONG
• The only hardcoded numbers permitted are: (1) raw historical inputs, (2) assumption drivers (growth rates, WACC inputs, terminal g), (3) current market data (share price, debt balance)
• If you catch yourself computing something in Python and writing the result — STOP. The model must flex when the user changes an assumption.

Verify Step-by-Step With the User (DO NOT build end-to-end):

• After data retrieval → show the user the raw inputs block (revenue, margins, shares, net debt) and confirm before projecting
• After revenue projections → show the projected top line and growth rates, confirm before building margin build
• After FCF build → show the full FCF schedule, confirm logic before computing WACC
• After WACC → show the calculation and inputs, confirm before discounting
• After terminal value + PV → show the equity bridge (EV → equity value → per share), confirm before sensitivity tables
• Catch errors at each stage — a wrong margin assumption discovered after sensitivity tables are built means rebuilding everything downstream

Sensitivity Tables:

• Use an ODD number of rows and columns (standard: 5×5, sometimes 7×7) — this guarantees a true center cell
• Center cell = base case. Build the axis values so the middle row header and middle column header exactly equal the model's actual assumptions (e.g., if base WACC = 9.0%, the middle row is 9.0%; if terminal g = 3.0%, the middle column is 3.0%). The center cell's output must therefore equal the model's actual implied share price — this is the sanity check that the table is built correctly.
• Highlight the center cell with the medium-blue fill (#BDD7EE) + bold font so it's immediately visible which cell is the base case.
• Populate ALL cells (typically 3 tables × 25 cells = 75) with full DCF recalculation formulas
• Use openpyxl loops (or Office JS loops) to write formulas programmatically
• NO placeholder text, NO linear approximations, NO manual steps required
• Each cell must recalculate full DCF for that assumption combination

Cell Comments:

• Add cell comments AS each hardcoded value is created
• Format: "Source: [System/Document], [Date], [Reference], [URL if applicable]"
• Every blue input must have a comment before moving to next section
• Do not defer to end or write "TODO: add source"

Model Layout Planning:

• Define ALL section row positions BEFORE writing any formulas
• Write ALL headers and labels first
• Write ALL section dividers and blank rows second
• THEN write formulas using the locked row positions
• Test formulas immediately after creation

Formula Recalculation:

• Run python recalc.py model.xlsx 30 before delivery
• Fix ALL errors until status is "success"
• Zero formula errors required (#REF!, #DIV/0!, #VALUE!, etc.)

Scenario Blocks:

• Create separate blocks for Bear/Base/Bull cases
• Show assumptions horizontally across projection years within each block
• Use IF formulas: =IF($B$6=1,[Bear cell],IF($B$6=2,[Base cell],[Bull cell]))
• Verify formulas reference correct scenario block cells

DCF Process Workflow

Step 1: Data Retrieval and Validation

Fetch data from MCP servers, user provided data, and the web.

Data Sources Priority:

1. MCP Servers (if configured) - Structured financial data from providers like Daloopa
2. User-Provided Data - Historical financials from their research
3. Web Search/Fetch - Current prices, beta, debt and cash when needed

Validation Checklist:

• Verify net debt vs net cash (critical for valuation)
• Confirm diluted shares outstanding (check for recent buybacks/issuances)
• Validate historical margins are consistent with business model
• Cross-check revenue growth rates with industry benchmarks
• Verify tax rate is reasonable (typically 21-28%)

Step 2: Historical Analysis (3-5 years)

Analyze and document:

• Revenue growth trends: Calculate CAGR, identify drivers
• Margin progression: Track gross margin, EBIT margin, FCF margin
• Capital intensity: D&A and CapEx as % of revenue
• Working capital efficiency: NWC changes as % of revenue growth
• Return metrics: ROIC, ROE trends

Create summary tables showing:

Historical Metrics (LTM):
Revenue: $X million
Revenue growth: X% CAGR
Gross margin: X%
EBIT margin: X%
D&A % of revenue: X%
CapEx % of revenue: X%
FCF margin: X%

Step 3: Build Revenue Projections

Methodology:

1. Start with latest actual revenue (LTM or most recent fiscal year)
2. Apply growth rates for each projection year
3. Show both dollar amounts AND calculated growth %

Growth Rate Framework:

• Year 1-2: Higher growth reflecting near-term visibility
• Year 3-4: Gradual moderation toward industry average
• Year 5+: Approaching terminal growth rate

Formula structure:

• Revenue(Y