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