Sheet — a spreadsheet with functions

A sheet is a spreadsheet document — cells, formulas, formatting — with the twist that it’s just another Vancetope document. Formulas evaluate server-side (Apache POI, the full Excel function pool), so an agent can drop inputs into cells, ask for a recalc, and read the results the exact same way you do.

This tour uses the infra-cost sheet in the demo project orbit-app (seed it with wb smoke showcase).

Table of contents

  1. The grid
  2. Formulas that compute
  3. Format a range
  4. It’s just a document
  5. Filled and read by agents
  6. Where to go next

The grid

Open the sheet and you get a familiar grid — lettered columns, numbered rows, inline cell editing. The infra-cost example totals a monthly infra bill: component, units, €/unit, and a computed €/mo column, with a Total / mo and Total / yr at the bottom.

Sheet — the infra-cost grid with computed totals

Formulas that compute

Cells hold values or formulas (=B2*C2, =SUM(D2:D5), =D7*12). A formula cell shows its result and carries a subtle left-edge marker; click into it and you see the formula itself. Change an input — say the Brain-pod count — and the totals recompute (server-side, then the grid updates).

Sheet — Edit mode showing the formulas behind the cells

Format a range

Formatting is per-cell and per-range. Drag out a rectangle and the panel tells you how many cells you grabbed (“4 cells”) and applies bold, alignment, number format (the €#,##0 on the money columns), text and background colour to all of them at once.

Sheet — a multi-cell selection with the format panel

It’s just a document

Because a sheet is a plain document, the Raw tab shows the JSON underneath — $meta, the schema, and each cell with its data (values and =… formulas) and formatting. CSV / XLSX import and export sit in the toolbar too.

Sheet — the Raw JSON view

Filled and read by agents

The eight sheet_* tools make the grid programmable: sheet_set_cell to write a value or formula, sheet_calc to recompute and persist the results, sheet_get_range to read a block back with its computed values. That’s the point of server-side evaluation — a recipe can treat a sheet as a calculation template: set the inputs, calc, read the answer.

Where to go next

  • The cell model, on-disk format and the full tool list: sheet spec.
  • Running a sheet from a script or compose block: Cortex tour.