Export Excel

Export structured tabular data to an Excel .xlsx file. A Node.js script using exceljs is written to a temp path, exceljs is installed locally if missing, and the script is run to produce the workbook. Output is written to the working directory as <filename>.xlsx.

When to use this skill

• User asks to export data to Excel, save as .xlsx, create a spreadsheet, or produce a file they can open in Excel or Google Sheets.
• The data is tabular (rows and columns) — query results, lists, comparison tables, reports.
• User says "I need an Excel file", "export this as a spreadsheet", "make an xlsx".

When NOT to use this skill

• User wants CSV — use the export-csv skill (simpler, no installation needed).
• User wants a PDF or HTML report — use make-pdf or make-html-report.
• The data is not tabular (free-form prose, charts only).
• User wants formulas or charts in the workbook — this skill produces data-only workbooks; complex Excel features are out of scope.

Workflow

Step 1: Check that Node.js is available

which node 2>/dev/null || echo "not found"

If not found, stop and tell the user:

"This skill requires Node.js. Install it from https://nodejs.org, then try again."

Do not proceed further.

Step 2: Create the tools directory

mkdir -p .ethos-work/tools

.ethos-work/ is the workspace's scratch directory for agent work. The Ethos state dir (~/.ethos) is not usable from the terminal: the terminal guard refuses any command that names it.

Step 3: Write the generator script

Use write_file to write a Node.js script to the relative path gen-excel.js, which resolves inside the working directory. The script should:

• Embed the data directly (as a JavaScript object literal).
• Use exceljs to create a workbook with one sheet per logical table.
• Set column headers from the data keys.
• Write each row of data.
• Save to the relative path <filename>.xlsx.

Minimal script template:

const ExcelJS = require('exceljs');

async function main() {
  const workbook = new ExcelJS.Workbook();
  const sheet = workbook.addWorksheet('Sheet1');

  // Set headers
  sheet.columns = [
    { header: 'Column A', key: 'colA', width: 20 },
    { header: 'Column B', key: 'colB', width: 20 },
  ];

  // Add rows
  const rows = [
    { colA: 'value1', colB: 'value2' },
  ];
  rows.forEach(row => sheet.addRow(row));

  await workbook.xlsx.writeFile('<filename>.xlsx');
  console.log('Done');
}

main().catch(err => { console.error(err); process.exit(1); });

Replace <filename> with a lowercase-hyphenated slug derived from the user's request (e.g. sales-data-2026-06). Embed the actual data in the rows array.

Step 4: Check if exceljs is available

test -d .ethos-work/tools/node_modules/exceljs && echo found || echo "not found"

If not found, install it locally:

npm install exceljs --prefix .ethos-work/tools

If install fails (no npm, no network, permission denied), stop and tell the user:

"This skill requires the exceljs npm package. Run: npm install exceljs --prefix .ethos-work/tools If npm is unavailable, ask your system administrator to install it."

Do not proceed further.

Step 5: Run the generator script

NODE_PATH="$PWD/.ethos-work/tools/node_modules" node gen-excel.js

Step 6: Confirm to the user

Tell the user:

"Excel file created at: <filename>.xlsx in the working directory — visible in the Documents tab."

Anti-patterns

• Do not install exceljs globally — use --prefix .ethos-work/tools to keep it isolated and avoid permission issues.
• Do not use an absolute output path in the script — write to a bare relative filename so the workbook lands in the working directory.
• Do not write a generic script and ask the user to fill in the data — embed the actual data in the script before running it.
• Do not produce an empty workbook — always include at least a header row.
• Do not reuse a stale gen-excel.js from a previous run without overwriting it with the current data.

Hard rules

• All generated files go to the working directory. Always write a relative path — never write the .xlsx outside the working directory.
• Always tell the user the exact output path after completion.
• If node is not installed, show the fallback message verbatim — do not proceed.
• If exceljs install fails, show the fallback message verbatim — do not proceed.
• The filename slug must be lowercase, hyphen-separated, and contain no spaces or special characters.