Columns

The column_spec array defines one entry per column.

Fields

Field	Type	Required	Description
id	string	Yes	Unique column identifier
align	string	No (default "left")	"left", "center", "right", "justify", or "char"
align_char	string?	No	Character for char alignment (e.g. ".")
width	string	Yes	"auto" or CSS length
min_width	string?	No	Minimum width
max_width	string?	No	Maximum width
style_id	string?	No	Default style for all cells in column
hidden	boolean	Yes	Whether column is hidden
label	string?	No	Column display label (accessibility)

Example

{
  "column_spec": [
    { "id": "col_0", "align": "left", "width": "150px", "hidden": false, "label": "Country" },
    { "id": "col_1", "align": "right", "width": "auto", "hidden": false, "label": "Population" },
    { "id": "col_2", "align": "center", "width": "1fr", "hidden": false, "label": "Region" }
  ]
}

Width Values

Value	Description
auto	Content-determined width
120px	Fixed pixel width
25%	Percentage of container
1fr	Fractional unit (like CSS grid)
3cm	Absolute length (cm, mm, in, pt)

min_width and max_width take the same forms except fr and auto. Widths may not be negative; an invalid width fails validation with INVALID_LENGTH (see Validation).