perf(vscode): fix performance issues with write tool (#7211)

* perf(vscode): fix performance issues with write tool

* refactor: remove packages/ui changes, defer to follow-up issue

* fix: preserve metadata.diagnostics in slimMeta

packages/kilo-vscode/src/KiloProvider.ts

@@ -40,6 +40,7 @@ import { resolveProjectDirectory } from "./project-directory"
 
 type KiloProviderOptions = {
   projectDirectory?: string | null
+  slimEditMetadata?: boolean
 }
 
 export class KiloProvider implements vscode.WebviewViewProvider, TelemetryPropertiesProvider {
@@ -90,6 +91,7 @@ export class KiloProvider implements vscode.WebviewViewProvider, TelemetryProper
   private ignoreControllerDir: string | null = null
   private marketplace: MarketplaceService | null = null
   private projectDirectory: string | null | undefined
+  private slimEditMetadata = true
 
   /** Optional interceptor called before the standard message handler.
    *  Return null to consume the message, or return a (possibly transformed) message. */
@@ -102,6 +104,7 @@ export class KiloProvider implements vscode.WebviewViewProvider, TelemetryProper
     options?: KiloProviderOptions,
   ) {
     this.projectDirectory = options?.projectDirectory
+    this.slimEditMetadata = options?.slimEditMetadata ?? true
     TelemetryProxy.getInstance().setProvider(this)
   }
 
@@ -135,6 +138,63 @@ export class KiloProvider implements vscode.WebviewViewProvider, TelemetryProper
     }
   }
 
+  // Edit tool parts carry full file contents in metadata.filediff.before/after.
+  // A session with many edits can produce multi-MB payloads serialized through
+  // postMessage on every session switch. Stripping those strings down to just
+  // file path + addition/deletion counts eliminates the dominant cost.
+
+  private slimMeta(meta: unknown) {
+    if (!this.slimEditMetadata) return meta
+    if (!meta || typeof meta !== "object") return undefined
+
+    const obj = meta as Record<string, unknown>
+    const filediff = obj.filediff
+    if (!filediff || typeof filediff !== "object") return undefined
+
+    const diff = filediff as Record<string, unknown>
+    const file = typeof diff.file === "string" ? diff.file : undefined
+    const additions = typeof diff.additions === "number" ? diff.additions : 0
+    const deletions = typeof diff.deletions === "number" ? diff.deletions : 0
+
+    const result: Record<string, unknown> = {
+      filediff: {
+        ...(file ? { file } : {}),
+        additions,
+        deletions,
+      },
+    }
+    // Preserve diagnostics so post-edit LSP errors still render
+    if (obj.diagnostics) result.diagnostics = obj.diagnostics
+    return result
+  }
+
+  /** Strip heavy metadata from a single edit tool part; pass-through for all other part types. */
+  private slimPart<T>(part: T): T {
+    if (!this.slimEditMetadata) return part
+    if (!part || typeof part !== "object") return part
+
+    const obj = part as Record<string, unknown>
+    if (obj.type !== "tool" || obj.tool !== "edit") return part
+
+    const state = obj.state
+    if (!state || typeof state !== "object") return part
+
+    const next = { ...(state as Record<string, unknown>) }
+    const meta = this.slimMeta(next.metadata)
+    if (meta) next.metadata = meta
+    else delete next.metadata
+
+    return {
+      ...obj,
+      state: next,
+    } as T
+  }
+
+  private slimParts<T>(parts: T[]) {
+    if (!this.slimEditMetadata) return parts
+    return parts.map((part) => this.slimPart(part))
+  }
+
   /**
    * Synchronize current extension-side state to the webview.
    * This is primarily used after a webview refresh where early postMessage calls
@@ -939,7 +999,7 @@ export class KiloProvider implements vscode.WebviewViewProvider, TelemetryProper
 
       const messages = messagesData.map((m) => ({
         ...m.info,
-        parts: m.parts,
+        parts: this.slimParts(m.parts),
         createdAt: new Date(m.info.time.created).toISOString(),
       }))
 
@@ -988,7 +1048,7 @@ export class KiloProvider implements vscode.WebviewViewProvider, TelemetryProper
 
       const messages = messagesData.map((m) => ({
         ...m.info,
-        parts: m.parts,
+        parts: this.slimParts(m.parts),
         createdAt: new Date(m.info.time.created).toISOString(),
       }))
 
@@ -1002,6 +1062,7 @@ export class KiloProvider implements vscode.WebviewViewProvider, TelemetryProper
         messages,
       })
     } catch (err) {
+      this.syncedChildSessions.delete(sessionID)
       console.error("[Kilo New] KiloProvider: Failed to sync child session:", err)
     }
   }
@@ -2281,6 +2342,13 @@ export class KiloProvider implements vscode.WebviewViewProvider, TelemetryProper
 
     const msg = mapSSEEventToWebviewMessage(event, sessionID)
     if (msg) {
+      if (msg.type === "partUpdated") {
+        this.postMessage({
+          ...msg,
+          part: this.slimPart(msg.part),
+        })
+        return
+      }
       this.postMessage(msg)
     }
   }

packages/kilo-vscode/src/agent-manager/AgentManagerProvider.ts

@@ -148,7 +148,9 @@ export class AgentManagerProvider implements vscode.Disposable {
 
     panel.webview.html = this.getHtml(panel.webview)
 
-    this.provider = new KiloProvider(this.extensionUri, this.connectionService, this.context)
+    this.provider = new KiloProvider(this.extensionUri, this.connectionService, this.context, {
+      slimEditMetadata: true,
+    })
     this.provider.attachToWebview(panel.webview, {
       onBeforeMessage: (msg) => this.onMessage(msg),
     })

packages/kilo-vscode/webview-ui/src/App.tsx

@@ -67,25 +67,16 @@ export const DataBridge: Component<{ children: any }> = (props) => {
 
   const data = createMemo(() => {
     const id = session.currentSessionID()
-    const allParts = session.allParts()
-    // Expose ALL session messages (including child sessions from sub-agents),
-    // not just the current session. This lets VscodeSessionTurn and
-    // TaskToolExpanded read child session data from the DataProvider store.
-    const allMessages = Object.fromEntries(
-      Object.entries(session.allMessages() as Record<string, SDKMessage[]>)
-        .filter(([, msgs]) => (msgs as SDKMessage[]).length > 0)
-        .map(([sid, msgs]) => [sid, msgs as SDKMessage[]]),
-    )
+    const family = session.familyData(id)
     return {
       session: session.sessions().map((s) => ({ ...s, id: s.id, role: "user" as const })) as unknown as any[],
-      session_status: session.allStatusMap() as unknown as Record<string, any>,
+      session_status: family.status as unknown as Record<string, any>,
       session_diff: {} as Record<string, any[]>,
-      message: allMessages,
-      part: Object.fromEntries(
-        Object.entries(allParts)
-          .filter(([, parts]) => (parts as SDKPart[]).length > 0)
-          .map(([msgId, parts]) => [msgId, parts as unknown as SDKPart[]]),
-      ),
+      // Restrict chat data to the selected session family (self + subagents).
+      // This keeps unrelated tracked sessions from invalidating the visible
+      // chat tree during streaming or background updates.
+      message: family.messages as Record<string, SDKMessage[]>,
+      part: family.parts as Record<string, SDKPart[]>,
       permission: (() => {
         const grouped: Record<string, any[]> = {}
         for (const p of session.permissions()) {

packages/kilo-vscode/webview-ui/src/components/chat/TaskToolExpanded.tsx

@@ -49,7 +49,8 @@ const TaskToolRenderer: Component<ToolProps> = (props) => {
 
   const running = createMemo(() => props.status === "pending" || props.status === "running")
 
-  // Sync child session into store whenever we have a sessionId
+  // Warm child session data immediately so completed task tools already have
+  // their compact child tool list available when the user expands them.
   createEffect(() => {
     const id = childSessionId()
     if (!id) return

packages/kilo-vscode/webview-ui/src/context/session.tsx

@@ -16,7 +16,7 @@ import {
   Accessor,
   batch,
 } from "solid-js"
-import { createStore, produce } from "solid-js/store"
+import { createStore, produce, reconcile } from "solid-js/store"
 import { useVSCode } from "./vscode"
 import { useServer } from "./server"
 import { useProvider } from "./provider"
@@ -87,6 +87,13 @@ interface SessionContextValue {
   // All session statuses keyed by sessionID (for DataBridge)
   allStatusMap: () => Record<string, SessionStatusInfo>
 
+  // Current session family data (self + subagents) for DataBridge
+  familyData: (sessionID: string | undefined) => {
+    messages: Record<string, Message[]>
+    parts: Record<string, Part[]>
+    status: Record<string, SessionStatusInfo>
+  }
+
   // Parts for a specific message
   getParts: (messageID: string) => Part[]
 
@@ -197,6 +204,7 @@ export const SessionProvider: ParentComponent = (props) => {
   }
 
   const [loading, setLoading] = createSignal(false)
+  const [loaded, setLoaded] = createSignal<Set<string>>(new Set())
 
   // Pending permissions
   const [permissions, setPermissions] = createSignal<PermissionRequest[]>([])
@@ -566,6 +574,12 @@ export const SessionProvider: ParentComponent = (props) => {
 
   function handleMessagesLoaded(sessionID: string, messages: Message[]) {
     batch(() => {
+      setLoaded((prev) => {
+        if (prev.has(sessionID)) return prev
+        const next = new Set(prev)
+        next.add(sessionID)
+        return next
+      })
       if (sessionID === currentSessionID()) setLoading(false)
 
       // Preserve optimistic messages that haven't been confirmed yet.
@@ -576,15 +590,15 @@ export const SessionProvider: ParentComponent = (props) => {
         const loadedIds = new Set(messages.map((m) => m.id))
         const current = store.messages[sessionID] ?? []
         const orphans = current.filter((m) => pending.has(m.id) && !loadedIds.has(m.id))
-        setStore("messages", sessionID, [...messages, ...orphans])
+        setStore("messages", sessionID, reconcile([...messages, ...orphans], { key: "id" }))
       } else {
-        setStore("messages", sessionID, messages)
+        setStore("messages", sessionID, reconcile(messages, { key: "id" }))
       }
 
       // Also extract parts from messages
       for (const msg of messages) {
         if (msg.parts && msg.parts.length > 0) {
-          setStore("parts", msg.id, msg.parts)
+          setStore("parts", msg.id, reconcile(msg.parts, { key: "id" }))
         }
       }
     })
@@ -806,6 +820,42 @@ export const SessionProvider: ParentComponent = (props) => {
     return family
   }
 
+  function familyData(sessionID: string | undefined) {
+    if (!sessionID) {
+      return {
+        messages: {},
+        parts: {},
+        status: {},
+      }
+    }
+
+    const family = sessionFamily(sessionID)
+    const messages: Record<string, Message[]> = {}
+    const parts: Record<string, Part[]> = {}
+    const status: Record<string, SessionStatusInfo> = {}
+
+    for (const sid of family) {
+      const msgs = store.messages[sid]
+      if (msgs?.length) {
+        messages[sid] = msgs
+        for (const msg of msgs) {
+          const item = store.parts[msg.id]
+          if (!item?.length) continue
+          parts[msg.id] = item
+        }
+      }
+
+      const info = statusMap[sid]
+      if (info) status[sid] = info
+    }
+
+    return {
+      messages,
+      parts,
+      status,
+    }
+  }
+
   /** Return permissions scoped to the given session's family (self + subagents). */
   function scopedPermissions(sessionID: string | undefined): PermissionRequest[] {
     if (!sessionID) return []
@@ -930,6 +980,12 @@ export const SessionProvider: ParentComponent = (props) => {
     if (cloudPreviewId() !== cloudSessionId) return
     const key = `cloud:${cloudSessionId}`
     batch(() => {
+      setLoaded((prev) => {
+        if (prev.has(key)) return prev
+        const next = new Set(prev)
+        next.add(key)
+        return next
+      })
       setStore("sessions", key, {
         id: key,
         title,
@@ -951,6 +1007,12 @@ export const SessionProvider: ParentComponent = (props) => {
     const cloudKey = `cloud:${cloudSessionId}`
     const cloudMessages = store.messages[cloudKey] ?? []
     batch(() => {
+      setLoaded((prev) => {
+        const next = new Set(prev)
+        next.add(session.id)
+        next.delete(cloudKey)
+        return next
+      })
       setStore("sessions", session.id, session)
 
       const pendingAgent = pendingAgentSelection()
@@ -1223,7 +1285,7 @@ export const SessionProvider: ParentComponent = (props) => {
       return
     }
     setCurrentSessionID(id)
-    setLoading(true)
+    setLoading(!loaded().has(id))
     vscode.postMessage({ type: "loadMessages", sessionID: id })
   }
 
@@ -1251,6 +1313,12 @@ export const SessionProvider: ParentComponent = (props) => {
         delete sessions[id]
       }),
     )
+    setLoaded((prev) => {
+      if (!prev.has(id)) return prev
+      const next = new Set(prev)
+      next.delete(id)
+      return next
+    })
     vscode.postMessage({ type: "deleteSession", sessionID: id })
   }
 
@@ -1421,6 +1489,7 @@ export const SessionProvider: ParentComponent = (props) => {
     allMessages,
     allParts,
     allStatusMap,
+    familyData,
     variantList,
     currentVariant,
     selectVariant,

packages/kilo-vscode/webview-ui/src/stories/StoryProviders.tsx

@@ -131,6 +131,7 @@ export function mockSessionValue(overrides?: {
     allMessages: () => ({}),
     allParts: () => ({}),
     allStatusMap: () => ({}),
+    familyData: () => ({ messages: {}, parts: {}, status: {} }),
     getParts: () => [],
     todos: () => [],
     permissions: () => permissions,

packages/kilo-vscode/webview-ui/src/stories/history.stories.tsx

@@ -61,6 +61,7 @@ const WithSessions: ParentComponent<{ sessions?: typeof mockSessions }> = (props
     allMessages: () => ({}),
     allParts: () => ({}),
     allStatusMap: () => ({}),
+    familyData: () => ({ messages: {}, parts: {}, status: {} }),
     getParts: () => [],
     todos: () => [],
     permissions: () => [],