> ## Documentation Index
> Fetch the complete documentation index at: https://docs.langstate.com/llms.txt
> Use this file to discover all available pages before exploring further.

# State in SUP

> The explicit artifact shared between update and presentation phases.

<Note>
  **Design note.** This SUP role is broader than any one shipped class.
</Note>

State is the shared artifact that allows updating and presentation to remain decoupled. It should expose stable field identity, current values or candidates, and enough provenance for the application to explain or correct changes.

LangState's interpretive and canonical states offer two concrete representations for this role. Repositories and snapshots are separate utilities; SUP does not require a specific database or persistence lifetime.

Good boundaries keep transcripts, provider-specific request objects, and UI component instances from becoming the only source of truth. Store those as related context when needed, while keeping application state explicit.