Convert Excel to Markdown

When to use this skill

Trigger this skill any time there is a .xlsx file that needs to be understood or processed — for example, a user attaches a spreadsheet and asks questions about it, wants a summary of the data, wants specific rows or values pulled out, or wants multiple workbooks in a folder processed together. Excel's native .xlsx format is a zipped XML bundle that is not reliably readable as plain text, so always convert it to Markdown first using the script in this skill rather than trying to open or parse the file directly.

This skill only supports .xlsx. If asked to convert a legacy .xls file, tell the user it isn't supported and ask them to re-save it as .xlsx (Excel: File > Save As > Excel Workbook (.xlsx)) first.

Mixed file types: When the user references a folder or set of documents containing multiple supported file types (.pdf, .docx, .xlsx), this skill handles only .xlsx files. The agent MUST also invoke the sibling skills in parallel:

• convert-pdf-to-md for any .pdf files
• convert-word-to-md for any .docx files

Never process a folder and silently skip a supported file type. All three skills must be invoked together when mixed types are present.

Setup (once per environment)

Before the first conversion in a given environment, follow references/setup.md step by step to ensure Python, pip, and the markitdown package are installed. Do this proactively rather than guessing whether the environment is ready — the script itself will also fail with a clear pointer back to that file if markitdown turns out to be missing, so it's safe to just try the conversion first if you're reasonably confident setup was already done.

Usage

The conversion script lives at scripts/convert_excel_to_md.py.

Output structure: MarkItDown's XLSX converter renders each sheet as its own ## <SheetName> Markdown table — it has no support for embedded images at all. This script separately extracts real embedded images (raster pictures, not charts) and maps them to the sheet they belong to, writing a self-contained folder per document:

<name>/
    img/
        sheet001_<sheetname>_img001.<ext>
        sheet002_<sheetname>_img001.<ext>
        ...
    <name>.md          (each sheet's images appear right after its table,
                         under a "#### Images in this sheet" heading)

This is per-sheet placement, not exact cell position — the finest granularity MarkItDown's stable output anchors (the ## <SheetName> headings) allow. If a workbook has no embedded images, no img/ folder or image sections are created. Native Excel charts are not extracted as images (only actual embedded pictures are — charts would need to be rendered by Excel/LibreOffice, which this lightweight skill does not do).

Single file:

powershell
python scripts\convert_excel_to_md.py "C:\path\to\workbook.xlsx"

This creates a workbook\ folder next to the source file (containing workbook.md and, if present, workbook\img\). To control the destination folder explicitly:

powershell
python scripts\convert_excel_to_md.py "C:\path\to\workbook.xlsx" -o "C:\path\to\output_folder"

A folder of workbooks (batch mode):

powershell
python scripts\convert_excel_to_md.py "C:\path\to\folder"

Add --recursive to also include subfolders:

powershell
python scripts\convert_excel_to_md.py "C:\path\to\folder" --recursive

Each .xlsx found gets its own <name>\ output folder next to it by default. Pass -o "C:\path\to\output_parent" to collect all the generated <name>\ folders under a separate parent directory instead (subfolder structure is preserved when combined with --recursive).

After conversion, read the resulting .md file(s) to perform the actual analysis the user asked for — the script's job is only to produce accurate Markdown (and images), not to interpret the content.

Deciding where output goes

Default — always output next to the source file. The <name>/ folder is created in the same directory as the source .xlsx. This is the required default for every case. Do NOT override it unless the user explicitly asks for a different location.

Only use -o when the user explicitly provides an output path (e.g., "save the output to C:\output", "put the results in D:\work"). Do NOT pass -o based on the agent's current working directory, the session state folder, or any implied location.

If the source file path cannot be fully resolved — for example, the user provides only a filename with no directory, or the path is ambiguous — use ask_user to confirm the full absolute path before running the conversion. Never guess or assume the directory.

Troubleshooting

| Symptom | Likely cause | Fix | |---|---|---| | ModuleNotFoundError: No module named 'markitdown' / exit code 2 | MarkItDown not installed | Follow references/setup.md | | ERROR: Unsupported file type '.xls' / exit code 3 | Legacy .xls, not .xlsx | Ask the user to re-save as .xlsx | | ERROR: Input path not found / exit code 3 | Wrong path, or file moved | Confirm the correct path with the user | | FAILED <file> -> ... in batch output | That specific file is corrupt, password-protected, or otherwise unreadable | Report which file(s) failed; other files in the batch still succeed | | NOTE: skipped N non-.xlsx file(s) | Folder contains non-Excel files | Expected — those files are intentionally ignored | | A sheet's charts don't appear as images | Charts are chart objects, not embedded pictures — this skill only extracts real embedded raster images | Expected; mention this limitation if the user specifically needs chart images |