agent-gl-reconciler-xlsx-author

name	agent-gl-reconciler-xlsx-author
description	Produce a .xlsx file on disk (headless) instead of driving a live Excel workbook — for headless Codex sessions with no open Office app. Use when users need to produce Excel workbooks as file artifacts with formulas, formatting, source notes, model checks, and recalculation guidance in general ledger reconciliation workflows.

xlsx-author

Use this skill when running headless (headless Codex mode) and you need to deliver an Excel workbook as a file artifact rather than editing a live workbook via available spreadsheet tools.

Output contract

• Write to ./out/<name>.xlsx. Create ./out/ if it does not exist.
• Return the relative path in your final message so the orchestration layer can collect it.

How to build the workbook

Write a short Python script and run it with Bash. Use openpyxl:

from openpyxl import Workbook
from openpyxl.styles import Font, PatternFill

wb = Workbook()
ws = wb.active; ws.title = "Inputs"
ws["B2"] = "Revenue"; ws["C2"] = 1_250_000_000
ws["C2"].font = Font(color="0000FF")           # blue = hardcoded input
calc = wb.create_sheet("DCF")
calc["C5"] = "=Inputs!C2*(1+Inputs!C3)"        # black = formula
wb.save("./out/model.xlsx")

Conventions (mirror audit-xls)

• Blue / black / green. Blue = hardcoded input, black = formula, green = link to another sheet/file.
• No hardcodes in calc cells. Every calculation cell is a formula; every input lives on an Inputs tab.
• Named ranges for any value referenced from a deck or memo.
• Balance checks. Include a Checks tab that ties (BS balances, CF ties to cash, etc.) and surfaces TRUE/FALSE.
• One model per file. Do not append to an existing workbook unless explicitly asked.

When NOT to use

If available spreadsheet tools tools are available (Cowork plugin mode), use those instead — they drive the user's live workbook with review checkpoints. This skill is the file-producing fallback for headless runs.