Checkpoitn

apps/sim/app/workspace/[workspaceId]/home/components/mothership-view/components/resource-content/resource-content.tsx

@@ -165,7 +165,9 @@ export const ResourceContent = memo(function ResourceContent({
     }
   }, [workspaceId, streamFileName])
 
-  const streamingFileMode: 'append' | 'replace' = isWriteStream ? 'append' : 'replace'
+  // workspace_file preview events now carry whole-file snapshots, not deltas.
+  // Treat every live preview as replace so the viewer shows the latest snapshot.
+  const streamingFileMode: 'append' | 'replace' = 'replace'
 
   // For existing file resources (not streaming-file), only pass streaming
   // content for patch operations where the preview splices new content into

apps/sim/app/workspace/[workspaceId]/home/hooks/use-chat.ts

@@ -610,11 +610,34 @@ export function useChat(
       const assistantId = generateId()
 
       const reconnect = async () => {
-        const succeeded = await retryReconnectRef.current({
-          streamId: activeStreamId,
-          assistantId,
-          gen,
-        })
+        const initialSnapshot = chatHistory.streamSnapshot
+        const snapshotEvents = Array.isArray(initialSnapshot?.events)
+          ? (initialSnapshot.events as StreamBatchEvent[])
+          : []
+
+        const reconnectResult =
+          snapshotEvents.length > 0
+            ? await attachToExistingStream({
+                streamId: activeStreamId,
+                assistantId,
+                expectedGen: gen,
+                initialBatch: {
+                  success: true,
+                  events: snapshotEvents,
+                  status: initialSnapshot?.status ?? 'unknown',
+                },
+                afterCursor: String(snapshotEvents[snapshotEvents.length - 1]?.eventId ?? '0'),
+              })
+            : null
+
+        const succeeded =
+          reconnectResult !== null
+            ? !reconnectResult.error || reconnectResult.aborted
+            : await retryReconnectRef.current({
+                streamId: activeStreamId,
+                assistantId,
+                gen,
+              })
         if (!succeeded && streamGenRef.current === gen) {
           try {
             finalizeRef.current({ error: true })

apps/sim/hooks/queries/tasks.ts

@@ -85,7 +85,9 @@ export async function fetchChatHistory(
     return {
       id: chat.id,
       title: chat.title,
-      messages: Array.isArray(chat.messages) ? chat.messages : [],
+      messages: Array.isArray(chat.messages)
+        ? chat.messages.map((m: Record<string, unknown>) => normalizeMessage(m))
+        : [],
       activeStreamId: chat.conversationId || null,
       resources: Array.isArray(chat.resources) ? chat.resources : [],
       streamSnapshot: chat.streamSnapshot || null,

apps/sim/lib/copilot/request/go/stream.ts

@@ -415,6 +415,7 @@ export async function runStreamLoop(
                 toolName: 'workspace_file',
                 previewPhase: 'file_preview_content',
                 content: streamedContent,
+                contentMode: 'snapshot',
               },
               ...(streamEvent.scope ? { scope: streamEvent.scope } : {}),
             })