> ## Documentation Index
> Fetch the complete documentation index at: https://invoca-5bd45748-mintlify-6c3474a6.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Select

> Divergences, open decisions, and undocumented gaps for Select.

See [Select](/invoca-design-system/components/forms/select) for the decided part of this page.

## Known issues

| ID                                                                             | Kind           | What                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| ------------------------------------------------------------------------------ | -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [**TITAN-DIV-24**](/invoca-design-system/foundations/divergences#titan-div-24) | Divergence     | The trigger's error focus ring is a third red, unaliased to the semantic error tokens — inherited from the field chrome it shares with Input                                                                                                                                                                                                                                                                                                                                                                                                                          |
| —                                                                              | Needs sign-off | This page previously pointed to a separate, undocumented "Combobox" for typing to filter options — that was wrong. Autocomplete is modeled as a mode of Select in the design library (an `Autocomplete` variant, `false`/`true`, on the same `Select Input` component as everything else on this page), not a separate component — see [Vocabulary](/invoca-design-system/components/forms/select#vocabulary). There is no `Combobox` page or component anywhere in the library's 49 pages. Titan's actual code structure for this is unconfirmed without a checkout. |

## Gaps in the current rules

* **No decided behavior for zero available options.**
* **No truncation rule for a long option label**, in either the trigger or the list.
* **No decided threshold for turning Autocomplete on** — the design library shows it as a
  binary mode, not a rule tied to option count.
* **Multi-select's trigger summary format is undecided** — a count, chips, and a truncated
  label list all satisfy [TITAN-SELECT-05](/invoca-design-system/components/forms/select#constraints) without choosing between them.
* **Whether the option-list overlay shares implementation with Menu** — the shared naming is suggestive, not confirmed against source.

## Constraints Titan should enforce

These are real, currently-true rules. Nothing in code stops a builder from violating them today —
each is a placeholder for a guardrail Titan hasn't built, not a decision still being made.

| ID                  | Constraint                                                             | Would be enforced by                                                   |
| ------------------- | ---------------------------------------------------------------------- | ---------------------------------------------------------------------- |
| **TITAN-SELECT-03** | The placeholder is never itself a selectable option.                   | A lint/runtime check comparing the placeholder text to the option set. |
| **TITAN-SELECT-04** | Option group headers are not selectable.                               | A test asserting group-header elements fire no selection handler.      |
| **TITAN-SELECT-05** | A multi-select trigger summarizes rather than growing unbounded.       | A built-in default `renderValue` truncation/summary utility.           |
| **TITAN-SELECT-06** | A disabled Select is paired with a reachable explanation.              | A required-when-disabled explanation prop.                             |
| **TITAN-SELECT-08** | Sub-options nest exactly one level, never deeper (needs confirmation). | A recursive type disallowing a third nesting level.                    |