The types

One set of twelve types is used for the columns of a table, for inputs and outputs, for the checking of a form, for the API description, for MCP tools and for the answers of an AI.

TypeScript

text(o?)
number(o?)
boolean(o?)
date(o?)      // a moment in time
day(o?)       // a calendar day with no time and no zone
choice(values, o?)
link(tableName, o?)
file(o?)
list(type, o?)
object(shape, o?)
json(o?)
vector(o)     // numbers for search by meaning

Each has a page of its own, as word.text, and so has each option of one, as option.text.min.

The options every type takes

Option	Means
`optional`	True for a value that may be left out. A value is required when it is left out
`default`	The value that stands in for one that was not given. On a `date`, `'now'` is the moment; on a `day`, `'today'` is the day. A `vector` takes none
`label`	The words a form shows beside the field: text, or a `message(...)` of the language files
`help`	The words a form shows under the field: text, or a `message(...)` of the language files

The options a column also takes

Option	Means
`unique`	No two rows hold the same value
`index`	The column is indexed
`private`	The value never leaves the server in a row: the `read` rule of the column that no caller passes, held by its paths below. A `private` column states no `search`
`personal`	The value is data about a person
`sealed`	The value is stored encrypted. `sealed: { findable: true }` keeps beside it a keyed fingerprint of the value, bound to the table and the column, so a filter of an equal value finds the row with nothing opened, and the same value in another column does not match. A sort and a range on it are `code.T2026`
`read`	Who may read the column: a rule, as the rules of a table are written, as `read: role('hr')`. A caller the rule does not let in gets each row without the column, also through a link, in a live answer and on a page, and a row that code with full access read loses it again where it leaves through a typed answer, a field of a group too; is refused a filter, a sort and a group by it (`code.T0013`); a search and a `near` are answered over the other columns, the column left out of what is matched, and a `near` by the column itself finds no row; and a group answers no value worked out from it. A rule that is a filter, as `where({ manager: caller('id') })`, lets the caller read the column of each row it fits. Code with full access reads it. In the description of the API, an MCP tool and the line of a tool the field is optional, and the line says who reads it, as `salary?: number (read by hr)`. A kept count stands under the rule of its own row: a builder who must hide it states `read` on it
`from`	The value is worked out from the row's own columns, or kept from the rows that link to its row: `count`, `sum`, `min` and `max` handed `{ of, by, where, column }`, as `number({ from: count({ of: orders, by: 'customer' }) })` (`word.count`)
`was`	The column's old name, or a list of them, where it was renamed
`by`	The work that fills the column: an action, a `python` or a model, as `by: summarize` or `by: { work, input, take }`. On a vector column that states its model: the columns whose words are turned into the vector, as `by: 'body'`
`old`	On a column that states `by`, and on a vector column: `'drop'` or `'keep'`, what becomes of the values it holds when its work or its model changes

A vector column takes neither unique nor index, and is always optional.

Values in code

Type	In TypeScript
`text`, `day`, `file`, `link`	`string`. A day is `'2026-10-08'`. A file and a link are ids
`number`	`number`
`boolean`	`boolean`
`date`	`Date` in backend code. On the wire it is text in the standard form
`choice`	The union of its values
`list`, `object`	A list and an object of the inner types
`json`	`unknown`
`vector`	`number[]`

A value that is not there is left out: an optional input that was not given is not in input. Given as an input, null means "not given". Inside a json value, null is kept as it is.

Two types of TypeScript say what a type means in code. Handed<typeof type> is what code is handed for a value of the type: a value that has a default is there, and a moment is a Date. Given<typeof type> is what a caller gives: a value that is optional or has a default may be left out, and a moment is a Date or text.

When a value does not fit

A value that does not fit its type is refused, and the error names each field that failed by its dotted name, with the name of the check it failed: see tent docs T0002.