diff --git a/NucleicRemote/NucleicRemote/Models/HostConnection.swift b/NucleicRemote/NucleicRemote/Models/HostConnection.swift
index 6021e0a..0753185 100644
--- a/NucleicRemote/NucleicRemote/Models/HostConnection.swift
+++ b/NucleicRemote/NucleicRemote/Models/HostConnection.swift
@@ -61,6 +61,15 @@ final class HostConnection {
     private var transcriptFetchRequestID: String?
     private var didStartFullFetch = false
 
+    /// The in-flight *background* transcript prefetch (one at a time): its request id, target
+    /// session, and accumulated chunks. Independent of the open-session fetch above — replies
+    /// are matched on this id, so the two flows never mix, and prefetching keeps working while a
+    /// different session is open on screen. Driven by RemoteStore, which warms the offline cache
+    /// with the result so a never-before-opened session still opens at its end instantly.
+    private var prefetchRequestID: String?
+    private var prefetchSessionID: SessionID?
+    private var prefetchEvents: [AgentEvent] = []
+
     // MARK: Callbacks up to RemoteStore (aggregate concerns)
 
     /// How a `HostConnection` talks back to `RemoteStore`. All fire on the main actor.