# X_TEST_ISLAND_STATE_UNKNOWN

## Means

an island state manifest declares no state with that id

## Typical cause

`mountIslandState(manifest, id)` or `describeIslandState(manifest, id, …)` named a state the manifest does not declare. A renamed state and a typo are one symptom, so `cause` lists every declared id

## Fix

name one of the ids the cause lists — or declare the state in the `<name>.island.states.ts` beside the island: `{ id: 'idle', title: 'the first paint', props: {} }`

[Testing](/error-codes#testing)