docs-internal/engine/ACTOR_KV.md
Each actor has its own private KV store which can be manipulated or accessed with the various provided KV operations.
A KV key is a byte array, aka a blob. A KV value is also a byte array/blob.
Every set KV value contains metadata which includes the version and create timestamp of the key (version being a string byte array denoting the version of the Rivet Engine).
Keys that don't exist aren't included in the output so it is important to read the output's list of keys.
This operation deletes all keys in the entire actor's KV store. Use cautiously.
Every operation can return an error instead of its regular response. The error includes a message string.
Each KV request has a u32 request ID which is to be provided by the user (handled internally by RivetKit). Rivet makes no attempt to order or deduplicate the responses to KV requests, it is up to the client to match the responses to the requests via the request ID.