> Fetch clean Markdown by appending `.md` to any page URL under https://signalwire.com/docs or requesting it with the HTTP header `Accept: text/markdown`. The root index at https://signalwire.com/docs/llms.txt lists the available documentation indexes. # Storage > Key-value storage interface for persisting SDK preferences and state. Key-value storage interface for persisting SDK preferences and state. ## **Methods** ### clear() ```ts clear(scope): Promise ``` Clears all keys in the given scope. Implementations may scope the clear to SDK keys only. #### Parameters **`scope`** `StorageScope` — required Storage scope (e.g. session vs. persistent). --- #### Returns `Promise` --- ### getItem() ```ts getItem(key, scope): Promise ``` #### Parameters **`key`** `string` — required Storage key to read or write. --- **`scope`** `StorageScope` — required Storage scope (e.g. session vs. persistent). --- #### Returns `Promise` --- ### removeItem() ```ts removeItem(key, scope): Promise ``` #### Parameters **`key`** `string` — required Storage key to read or write. --- **`scope`** `StorageScope` — required Storage scope (e.g. session vs. persistent). --- #### Returns `Promise` --- ### setItem() ```ts setItem(key, value, scope): Promise ``` #### Parameters **`key`** `string` — required Storage key to read or write. --- **`value`** `string | null` — required Value to write, or `null` to clear the key. --- **`scope`** `StorageScope` — required Storage scope (e.g. session vs. persistent). --- #### Returns `Promise` > Key-value storage interface for persisting SDK preferences and state.