@@ -342,6 +342,23 @@ export namespace Session {
     return part
   })
 
+  export const removePart = fn(
+    z.object({
+      sessionID: Identifier.schema("session"),
+      messageID: Identifier.schema("message"),
+      partID: Identifier.schema("part"),
+    }),
+    async (input) => {
+      await Storage.remove(["part", input.messageID, input.partID])
+      Bus.publish(MessageV2.Event.PartRemoved, {
+        sessionID: input.sessionID,
+        messageID: input.messageID,
+        partID: input.partID,
+      })
+      return input.partID
+    },
+  )
+
   export const getUsage = fn(
     z.object({
       model: z.custom<ModelsDev.Model>(),
 
@@ -916,21 +916,22 @@ export namespace SessionPrompt {
                   const part = reasoningMap[value.id]
                   part.text += value.text
                   if (value.providerMetadata) part.metadata = value.providerMetadata
-                  if (part.text) await Session.updatePart(part)
+                  if (part.text.trim()) await Session.updatePart(part)
                 }
                 break
 
               case "reasoning-end":
                 if (value.id in reasoningMap) {
                   const part = reasoningMap[value.id]
                   part.text = part.text.trimEnd()
-
-                  part.time = {
-                    ...part.time,
-                    end: Date.now(),
+                  if (part.text) {
+                    part.time = {
+                      ...part.time,
+                      end: Date.now(),
+                    }
+                    if (value.providerMetadata) part.metadata = value.providerMetadata
+                    await Session.updatePart(part)
                   }
-                  if (value.providerMetadata) part.metadata = value.providerMetadata
-                  await Session.updatePart(part)
                   delete reasoningMap[value.id]
                 }
                 break
@@ -1085,19 +1086,21 @@ export namespace SessionPrompt {
                 if (currentText) {
                   currentText.text += value.text
                   if (value.providerMetadata) currentText.metadata = value.providerMetadata
-                  if (currentText.text) await Session.updatePart(currentText)
+                  if (currentText.text.trim()) await Session.updatePart(currentText)
                 }
                 break
 
               case "text-end":
                 if (currentText) {
                   currentText.text = currentText.text.trimEnd()
-                  currentText.time = {
-                    start: Date.now(),
-                    end: Date.now(),
+                  if (currentText.text) {
+                    currentText.time = {
+                      start: Date.now(),
+                      end: Date.now(),
+                    }
+                    if (value.providerMetadata) currentText.metadata = value.providerMetadata
+                    await Session.updatePart(currentText)
                   }
-                  if (value.providerMetadata) currentText.metadata = value.providerMetadata
-                  await Session.updatePart(currentText)
                 }
                 currentText = undefined
                 break