Spreadsheet editing

Create and edit Excel workbooks in the agent workspace — values, formulae, formatting, rows/columns, merges and freeze panes. Spreadsheets only (no Word or PowerPoint).

Slug: spreadsheet-editing Unlocks tools: xlsx_read, xlsx_set_cell, xlsx_set_range, xlsx_append_rows, xlsx_add_sheet, xlsx_create, xlsx_delete_rows, xlsx_format_range, xlsx_insert_rows, xlsx_insert_columns, xlsx_delete_columns, xlsx_merge_cells, xlsx_unmerge_cells, xlsx_set_column_widths, xlsx_freeze_panes, xlsx_find_cells

The rest of this page is the exact guidance this skill injects into an agent's system prompt.

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Spreadsheet editing discipline

This skill unlocks the xlsx_* tools for working with Excel workbooks stored in the agent's workspace.

Path conventions

All Office tools take a workspace-relative path. For agents with a single workspace the label is optional (e.g. report.xlsx). For agents with multiple workspaces, prefix with the workspace label and a slash (e.g. docs/report.xlsx for the workspace labelled "docs"). Never use absolute paths.

Read → modify → save discipline

1. Always read before writing. Call xlsx_read first to confirm the file exists and understand its current state.
2. One operation at a time. Prefer targeted mutations (xlsx_set_cell, xlsx_set_range) over full rewrites when only part of the content changes.
3. Fail loud on error. If a tool returns ok:false, surface the reason to the user immediately. Do NOT silently retry a different path.

Use xlsx_find_cells to locate data before mutating it. xlsx_delete_rows and xlsx_delete_columns are irreversible — confirm the range with xlsx_read first and present what will be deleted before proceeding.

Capabilities

Read with xlsx_read and xlsx_find_cells; create with xlsx_create; edit in place with full fidelity — values, formulae (=SUM(...)), formatting (xlsx_format_range), and structure (insert/delete rows and columns, merge, widths, freeze panes). Styles and formulae elsewhere in the workbook are preserved.

Known limits — state them, never work around them silently

• Formulae are written, not computed: =SUM(B2:B10) is stored and recalculates when the user opens the file. Reading a formula cell returns the formula (and the last cached value if present), not a fresh computation.
• No pivot-table or chart support (library limit): they cannot be created, and the library cannot preserve existing ones through an edit either — so any mutation tool REFUSES a workbook that contains charts or pivot tables (ok:false with the reason) instead of silently destroying them. Tell the user why, and offer to work on a copy without the charts, or compute the aggregation yourself and write a formatted summary sheet with formulas.
• 25 MiB cap per file (read and write). Inform the user and suggest splitting if exceeded.

When to ask for confirmation

• Before xlsx_delete_rows / xlsx_delete_columns: always confirm range and expected impact.
• Before xlsx_create with overwrite:true: confirm the file should be replaced.