XLSX

Requirements for Outputs

All Excel files

Professional Font

• Use a consistent, professional font (e.g., Arial, Times New Roman) for all deliverables unless otherwise instructed by the user

Zero Formula Errors

• Every Excel model MUST be delivered with ZERO formula errors (#REF!, #DIV/0!, #VALUE!, #N/A, #NAME?)
• Always verify with: Spreadsheet { action: "check_errors", file_path: "output.xlsx" }

Preserve Existing Templates (when updating templates)

• Study and EXACTLY match existing format, style, and conventions when modifying files
• Never impose standardized formatting on files with established patterns
• Existing template conventions ALWAYS override these guidelines

Financial models

Color Coding Standards

Unless otherwise stated by the user or existing template

Industry-Standard Color Conventions

• Blue text (RGB: 0,0,255): Hardcoded inputs, and numbers users will change for scenarios
• Black text (RGB: 0,0,0): ALL formulas and calculations
• Green text (RGB: 0,128,0): Links pulling from other worksheets within same workbook
• Red text (RGB: 255,0,0): External links to other files
• Yellow background (RGB: 255,255,0): Key assumptions needing attention or cells that need to be updated

Number Formatting Standards

Required Format Rules

• Years: Format as text strings (e.g., "2024" not "2,024")
• Currency: Use $#,##0 format; ALWAYS specify units in headers ("Revenue ($mm)")
• Zeros: Use number formatting to make all zeros "-", including percentages (e.g., "$#,##0;($#,##0);-")
• Percentages: Default to 0.0% format (one decimal)
• Multiples: Format as 0.0x for valuation multiples (EV/EBITDA, P/E)
• Negative numbers: Use parentheses (123) not minus -123

Formula Construction Rules

Assumptions Placement

• Place ALL assumptions (growth rates, margins, multiples, etc.) in separate assumption cells
• Use cell references instead of hardcoded values in formulas
• Example: Use =B5*(1+$B$6) instead of =B5*1.05

Formula Error Prevention

• Verify all cell references are correct
• Check for off-by-one errors in ranges
• Ensure consistent formulas across all projection periods
• Test with edge cases (zero values, negative numbers)
• Verify no unintended circular references

Documentation Requirements for Hardcodes

• Comment or in cells beside (if end of table). Format: "Source: [System/Document], [Date], [Specific Reference], [URL if applicable]"
• Examples:
  • "Source: Company 10-K, FY2024, Page 45, Revenue Note, [SEC EDGAR URL]"
  • "Source: Bloomberg Terminal, 8/15/2025, AAPL US Equity"

Workflow

Use the Spreadsheet tool for everything

The Spreadsheet tool handles ALL operations natively — no Python, no Bash, no dependencies.

Available actions

• Reading: inspect, list_sheets, get_sheet_info, read_range
• Writing: write_range, append_rows, set_cell (supports formulas: value: "=SUM(A1:A10)")
• Searching: find_text
• Validation: check_errors, inspect_formulas
• Formatting: format_cells, set_column_width
• Structure: create, add_sheet
• Export: export_csv

Do NOT use Python/Bash for spreadsheet operations. The Spreadsheet tool is the single source of truth.

Common Workflows

1. Inspect an existing file

Spreadsheet { action: "inspect", file_path: "data.xlsx" }
Spreadsheet { action: "list_sheets", file_path: "data.xlsx" }
Spreadsheet { action: "read_range", file_path: "data.xlsx", sheet: "Summary", range: "A1:F20" }

2. Create a new workbook

Spreadsheet { action: "create", file_path: "output.xlsx", sheets: ["Summary", "Data", "Assumptions"] }
Spreadsheet { action: "write_range", file_path: "output.xlsx", sheet: "Summary", range: "A1", values: [["Revenue","Q1","Q2","Q3","Q4"],["Product A",100,120,130,150]] }
Spreadsheet { action: "format_cells", file_path: "output.xlsx", sheet: "Summary", range: "A1:E1", format: {"bold": true, "fill": "4472C4", "color": "FFFFFF"} }
Spreadsheet { action: "set_column_width", file_path: "output.xlsx", column: "A", width: 20 }

3. Edit existing data

Spreadsheet { action: "read_range", file_path: "model.xlsx", sheet: "Input" }
Spreadsheet { action: "set_cell", file_path: "model.xlsx", sheet: "Input", cell: "B5", value: "150000" }
Spreadsheet { action: "append_rows", file_path: "model.xlsx", sheet: "Data", rows: [["2026-Q1", 250, 180, 70]] }

4. Verify and fix errors

Spreadsheet { action: "check_errors", file_path: "output.xlsx" }

Returns:

{
  "status": "success",
  "totalErrors": 0,
  "formulaCount": 42,
  "errorSummary": {}
}

Or if errors found:

{
  "status": "errors_found",
  "totalErrors": 3,
  "formulaCount": 42,
  "errorSummary": {
    "#REF!": { "count": 2, "locations": ["Sheet1!B5", "Sheet1!C10"] },
    "#DIV/0!": { "count": 1, "locations": ["Sheet1!D15"] }
  }
}

Fix the identified errors and check again until status: "success".

5. Search across sheets

Spreadsheet { action: "find_text", file_path: "report.xlsx", query: "revenue" }

6. Export to CSV

Spreadsheet { action: "export_csv", file_path: "data.xlsx", sheet: "Summary" }

7. Financial model with formulas

Spreadsheet { action: "create", file_path: "model.xlsx", sheets: ["Model"] }
Spreadsheet { action: "set_cell", file_path: "model.xlsx", sheet: "Model", cell: "A1", value: "Revenue" }
Spreadsheet { action: "set_cell", file_path: "model.xlsx", sheet: "Model", cell: "B1", value: "Q1" }
Spreadsheet { action: "format_cells", file_path: "model.xlsx", sheet: "Model", range: "A1:B1", format: {"bold": true} }
Spreadsheet { action: "set_cell", file_path: "model.xlsx", sheet: "Model", cell: "B2", value: "100" }
Spreadsheet { action: "set_cell", file_path: "model.xlsx", sheet: "Model", cell: "B3", value: "=B2*1.1" }
Spreadsheet { action: "set_cell", file_path: "model.xlsx", sheet: "Model", cell: "B4", value: "=SUM(B2:B3)" }
Spreadsheet { action: "check_errors", file_path: "model.xlsx" }

Format Reference

format_cells options

{
  "bold": true,
  "italic": false,
  "color": "FF0000",
  "fill": "FFFF00",
  "numFmt": "$#,##0",
  "alignment": { "horizontal": "center", "vertical": "center" }
}

Financial color coding via format_cells

// Blue inputs
Spreadsheet { action: "format_cells", file_path: "model.xlsx", range: "B5:B10", format: {"color": "0000FF"} }
// Yellow assumptions
Spreadsheet { action: "format_cells", file_path: "model.xlsx", range: "B2:B4", format: {"fill": "FFFF00"} }
// Bold headers
Spreadsheet { action: "format_cells", file_path: "model.xlsx", range: "A1:F1", format: {"bold": true, "fill": "4472C4", "color": "FFFFFF"} }

Quick Reference