[Home](./index.md) > [@workgrid/client](./client.md) > [MutationKey](./client.mutationkey.md) ## MutationKey type > This API is provided as a preview for developers and may change based on feedback that we receive. Do not use this API in a production environment. > Signature: ```typescript type MutationKey = Q['TMutationKey'] extends string | [string] ? K | [K] : Q['TMutationKey'] extends [string, ...infer R] ? [K, ...R] : never; ```