fix: reduce renderer memory accumulation

.changeset/renderer-memory-guardrails.md

@@ -0,0 +1,6 @@
+---
+"kilo-code": patch
+"@kilocode/cli": patch
+---
+
+Reduce memory use when switching long VS Code sessions while preserving queued prompts, unsent drafts, and inline edit diffs.

packages/kilo-vscode/src/kilo-provider/slim-metadata.ts

@@ -182,6 +182,63 @@ function slimBash(state: Record<string, unknown>): Record<string, unknown> {
   return next
 }
 
+/** websearch: preserve provider metadata and cap rendered results. */
+function slimWebsearch(state: Record<string, unknown>): Record<string, unknown> {
+  const next = slimOutput(state)
+  const meta = state.metadata
+  if (isObj(meta)) {
+    const slim: Record<string, unknown> = {}
+    if (typeof meta.provider === "string") slim.provider = meta.provider
+    next.metadata = slim
+  }
+  return next
+}
+
+/** webfetch: preserve the requested URL and cap rendered response content. */
+function slimWebfetch(state: Record<string, unknown>): Record<string, unknown> {
+  const next = slimOutput(state)
+  const input = state.input
+  if (isObj(input)) {
+    const slim: Record<string, unknown> = {}
+    if (typeof input.url === "string") slim.url = input.url
+    next.input = slim
+  }
+  return next
+}
+
+/** codesearch: preserve query/token count and cap rendered results. */
+function slimCodesearch(state: Record<string, unknown>): Record<string, unknown> {
+  const next = slimOutput(state)
+  const input = state.input
+  if (isObj(input)) {
+    const slim: Record<string, unknown> = {}
+    if (typeof input.query === "string") slim.query = input.query
+    if (typeof input.tokensNum === "number") slim.tokensNum = input.tokensNum
+    next.input = slim
+  }
+  return next
+}
+
+/** task: preserve rendered labels and sessionId while capping sub-agent output. */
+function slimTask(state: Record<string, unknown>): Record<string, unknown> {
+  const next = slimOutput(state)
+  const input = state.input
+  if (isObj(input)) {
+    const slim: Record<string, unknown> = {}
+    if (typeof input.description === "string") slim.description = input.description
+    if (typeof input.subagent_type === "string") slim.subagent_type = input.subagent_type
+    if (typeof input.sessionId === "string") slim.sessionId = input.sessionId
+    next.input = slim
+  }
+  const meta = state.metadata
+  if (isObj(meta) && typeof meta.sessionId === "string") {
+    next.metadata = { sessionId: meta.sessionId }
+  } else {
+    delete next.metadata
+  }
+  return next
+}
+
 // ---------------------------------------------------------------------------
 // Public API
 // ---------------------------------------------------------------------------
@@ -214,6 +271,10 @@ const slimmers: Record<string, (state: Record<string, unknown>) => Record<string
   multiedit: slimMultiedit,
   write: slimWrite,
   bash: slimBash,
+  websearch: slimWebsearch,
+  webfetch: slimWebfetch,
+  codesearch: slimCodesearch,
+  task: slimTask,
 }
 
 /** Strip provider metadata that the webview never reads from reasoning parts. */

packages/kilo-vscode/tests/unit/message-list-queue-contract.test.ts

@@ -0,0 +1,23 @@
+import { describe, expect, it } from "bun:test"
+import fs from "node:fs"
+import path from "node:path"
+
+const file = path.resolve(import.meta.dir, "../../webview-ui/src/components/chat/MessageList.tsx")
+const source = fs.readFileSync(file, "utf-8")
+
+function virtualizer() {
+  const start = source.indexOf("<Virtualizer")
+  const end = source.indexOf("</Virtualizer>", start)
+  return source.slice(start, end)
+}
+
+describe("MessageList rendering", () => {
+  it("marks only partitioned queued turns as queued", () => {
+    expect(virtualizer()).not.toContain("queued=")
+    expect(source).toMatch(/<For each=\{partition\(\)\.queued\}>[\s\S]*?<VscodeSessionTurn turn=\{turn\} queued \/>/)
+  })
+
+  it("disables automatic history expansion when configured", () => {
+    expect(source).toContain("config().auto_expand_history === false")
+  })
+})

packages/kilo-vscode/tests/unit/prompt-drafts.test.ts

@@ -1,6 +1,31 @@
-import { describe, it, expect } from "bun:test"
+import { beforeEach, describe, it, expect } from "bun:test"
+import { deleteDraftsForSession, drafts, imageDrafts, reviewDrafts } from "../../webview-ui/src/utils/draft-store"
 import { pendingDraftKey, scopeDraftKey, sessionDraftKey } from "../../webview-ui/src/utils/prompt-drafts"
 
+beforeEach(() => {
+  drafts.clear()
+  reviewDrafts.clear()
+  imageDrafts.clear()
+})
+
+describe("deleteDraftsForSession", () => {
+  it("clears deleted-session drafts without touching other sessions", () => {
+    drafts.set("prompt:default:session:a", "draft a")
+    drafts.set("prompt:default:pending:a", "pending a")
+    drafts.set("prompt:default:session:b", "draft b")
+    reviewDrafts.set("prompt:default:session:a", [])
+    imageDrafts.set("prompt:default:session:a", [])
+
+    deleteDraftsForSession("a")
+
+    expect(drafts.has("prompt:default:session:a")).toBe(false)
+    expect(drafts.has("prompt:default:pending:a")).toBe(false)
+    expect(drafts.get("prompt:default:session:b")).toBe("draft b")
+    expect(reviewDrafts.has("prompt:default:session:a")).toBe(false)
+    expect(imageDrafts.has("prompt:default:session:a")).toBe(false)
+  })
+})
+
 describe("sessionDraftKey", () => {
   it("prefixes session ids", () => {
     expect(sessionDraftKey("abc")).toBe("session:abc")

packages/kilo-vscode/tests/unit/prompt-send-contract.test.ts

@@ -17,6 +17,7 @@ import path from "node:path"
 const ROOT = path.resolve(import.meta.dir, "../..")
 const SESSION_FILE = path.join(ROOT, "webview-ui/src/context/session.tsx")
 const CHATVIEW_FILE = path.join(ROOT, "webview-ui/src/components/chat/ChatView.tsx")
+const PROMPT_INPUT_FILE = path.join(ROOT, "webview-ui/src/components/chat/PromptInput.tsx")
 const PROMPT_UTILS_FILE = path.join(ROOT, "webview-ui/src/components/chat/prompt-input-utils.ts")
 
 function readFile(filePath: string): string {
@@ -75,6 +76,32 @@ describe("sendCommand dismisses pending tool requests", () => {
   })
 })
 
+describe("session draft retention contract", () => {
+  const source = readFile(SESSION_FILE)
+  const input = readFile(PROMPT_INPUT_FILE)
+  const select = extractFunctionBody(source, "selectSession")
+  const remove = extractFunctionBody(source, "handleSessionDeleted")
+
+  it("does not treat a session switch as draft deletion", () => {
+    expect(select).not.toContain("deleteDraftsForSession")
+    expect(select).not.toContain("sessionDeleted")
+  })
+
+  it("cleans the draft maps only on real deletion", () => {
+    expect(input).toContain('import { drafts, imageDrafts, reviewDrafts } from "../../utils/draft-store"')
+    expect(remove).toContain("deleteDraftsForSession(sessionID)")
+  })
+
+  it("clears off-store transcript caches unless the session becomes active again", () => {
+    const guard = select.indexOf("if (currentSessionID() === oldID) return")
+    const cleanup = select.indexOf("stash.remove(mid)")
+
+    expect(guard).toBeGreaterThan(-1)
+    expect(cleanup).toBeGreaterThan(guard)
+    expect(select).toContain("delete map[oldID]")
+  })
+})
+
 describe("ChatView prompt-block contract", () => {
   const source = readFile(CHATVIEW_FILE)
 

packages/kilo-vscode/tests/unit/slim-metadata.test.ts

@@ -367,4 +367,72 @@ describe("slimPart", () => {
       expect(bytes(slimPart(heavy))).toBeLessThan(MAX_SLIM_BYTES)
     })
   })
+
+  // -----------------------------------------------------------------------
+  // websearch / webfetch / codesearch / task
+  // -----------------------------------------------------------------------
+  describe("web tools", () => {
+    it("caps websearch output and preserves provider metadata", () => {
+      const heavy = part("websearch", {
+        status: "completed",
+        input: { query: "renderer memory" },
+        output: BIG,
+        metadata: { provider: "exa", results: BIG },
+      })
+      const slim = slimPart(heavy) as Record<string, any>
+
+      expect(slim.state.output.length).toBeLessThan(BIG.length)
+      expect(slim.state.metadata).toEqual({ provider: "exa" })
+      expect(bytes(slim)).toBeLessThan(MAX_SLIM_BYTES)
+    })
+
+    it("caps webfetch output and preserves only the URL input", () => {
+      const heavy = part("webfetch", {
+        status: "completed",
+        input: { url: "https://example.com", format: "markdown" },
+        output: BIG,
+        metadata: {},
+      })
+      const slim = slimPart(heavy) as Record<string, any>
+
+      expect(slim.state.output.length).toBeLessThan(BIG.length)
+      expect(slim.state.input).toEqual({ url: "https://example.com" })
+      expect(bytes(slim)).toBeLessThan(MAX_SLIM_BYTES)
+    })
+
+    it("caps codesearch output and preserves query/token inputs", () => {
+      const heavy = part("codesearch", {
+        status: "completed",
+        input: { query: "SolidJS createMemo", tokensNum: 5000, extra: BIG },
+        output: BIG,
+        metadata: {},
+      })
+      const slim = slimPart(heavy) as Record<string, any>
+
+      expect(slim.state.output.length).toBeLessThan(BIG.length)
+      expect(slim.state.input).toEqual({ query: "SolidJS createMemo", tokensNum: 5000 })
+      expect(bytes(slim)).toBeLessThan(MAX_SLIM_BYTES)
+    })
+  })
+
+  describe("task", () => {
+    it("caps output and preserves only rendered input plus child session metadata", () => {
+      const heavy = part("task", {
+        status: "completed",
+        input: { description: "Explore renderer", prompt: BIG, subagent_type: "explore", sessionId: "child" },
+        output: BIG,
+        metadata: { sessionId: "child", model: BIG },
+      })
+      const slim = slimPart(heavy) as Record<string, any>
+
+      expect(slim.state.output.length).toBeLessThan(BIG.length)
+      expect(slim.state.input).toEqual({
+        description: "Explore renderer",
+        subagent_type: "explore",
+        sessionId: "child",
+      })
+      expect(slim.state.metadata).toEqual({ sessionId: "child" })
+      expect(bytes(slim)).toBeLessThan(MAX_SLIM_BYTES)
+    })
+  })
 })

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

@@ -17,6 +17,7 @@ import { createAutoScroll } from "@kilocode/kilo-ui/hooks"
 import { useSession } from "../../context/session"
 import { useServer } from "../../context/server"
 import { useLanguage } from "../../context/language"
+import { useConfig } from "../../context/config"
 import { recentSessions } from "../../context/session-utils"
 import { formatRelativeDate } from "../../utils/date"
 import { FeedbackDialog } from "./FeedbackDialog"
@@ -68,6 +69,7 @@ export const MessageList: Component<MessageListProps> = (props) => {
   const session = useSession()
   const server = useServer()
   const language = useLanguage()
+  const { config } = useConfig()
   const dialog = useDialog()
 
   const autoScroll = createAutoScroll({
@@ -143,7 +145,7 @@ export const MessageList: Component<MessageListProps> = (props) => {
 
   const maybeLoadOlder = () => {
     const el = scrollEl()
-    if (!el || el.scrollTop > 600) return
+    if (!el || el.scrollTop > 600 || config().auto_expand_history === false) return
     session.loadOlderMessages()
   }
 

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

@@ -48,13 +48,9 @@ import {
 } from "./prompt-input-utils"
 import type { ReviewComment, TextPart } from "../../types/messages"
 import { formatReviewCommentsMarkdown } from "../../utils/review-comment-markdown"
+import { drafts, imageDrafts, reviewDrafts } from "../../utils/draft-store"
 import { pendingDraftKey, scopeDraftKey, sessionDraftKey } from "../../utils/prompt-drafts"
 
-// Per-session input text storage (module-level so it survives remounts)
-const drafts = new Map<string, string>()
-const reviewDrafts = new Map<string, ReviewComment[]>()
-const imageDrafts = new Map<string, ImageAttachment[]>()
-
 function mergeReviewComments(current: ReviewComment[], incoming: ReviewComment[]): ReviewComment[] {
   if (incoming.length === 0) return current
   const map = new Map(current.map((item) => [item.id, item]))

packages/kilo-vscode/webview-ui/src/components/settings/DisplayTab.tsx

@@ -99,6 +99,19 @@ const DisplayTab: Component = () => {
           </Switch>
         </SettingsRow>
 
+        <SettingsRow
+          title={language.t("settings.display.autoExpandHistory.title")}
+          description={language.t("settings.display.autoExpandHistory.description")}
+        >
+          <Switch
+            checked={config().auto_expand_history !== false}
+            onChange={(checked: boolean) => updateConfig({ auto_expand_history: checked ? undefined : false })}
+            hideLabel
+          >
+            {language.t("settings.display.autoExpandHistory.title")}
+          </Switch>
+        </SettingsRow>
+
         <SettingsRow
           title={language.t("settings.display.terminalCommand.title")}
           description={language.t("settings.display.terminalCommand.description")}

packages/kilo-vscode/webview-ui/src/components/settings/settings-io.ts

@@ -35,6 +35,7 @@ export const KNOWN_KEYS: ReadonlyArray<string> = [
   "tools",
   "layout",
   "auto_collapse_reasoning",
+  "auto_expand_history",
   "terminal_command_display",
   "indexing",
   "experimental",

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

@@ -60,6 +60,7 @@ import { state as todoState } from "./todo-revert"
 import { getVariant, sessionVariantKeys, transferVariants, variantKey } from "./session-variant-store"
 import { KILO_AUTO, parseModelString } from "../../../src/shared/provider-model"
 import { visibleMessages as filterVisibleMessages } from "./session-queue"
+import { deleteDraftsForSession } from "../utils/draft-store"
 
 const RECENT_LIMIT = 5
 const MESSAGE_PAGE_LIMIT = 80
@@ -1700,6 +1701,7 @@ export const SessionProvider: ParentComponent = (props) => {
         setLoading(false)
       }
     })
+    deleteDraftsForSession(sessionID)
   }
 
   // Splices the message from the store and deletes its parts.
@@ -2190,7 +2192,53 @@ export const SessionProvider: ParentComponent = (props) => {
       console.warn("[Kilo New] Cannot select cloud preview session via selectSession")
       return
     }
+    const oldID = currentSessionID()
     const ready = loaded().has(id)
+    if (oldID && oldID !== id) {
+      const msgs = store.messages[oldID] ?? []
+      const msgIds = msgs.map((m) => m.id)
+      queueMicrotask(() => {
+        if (currentSessionID() === oldID) return
+        for (const mid of msgIds) stash.remove(mid)
+        setStore(
+          "messages",
+          produce((messages) => {
+            delete messages[oldID]
+          }),
+        )
+        setStore(
+          "parts",
+          produce((parts) => {
+            for (const mid of msgIds) {
+              delete parts[mid]
+            }
+          }),
+        )
+        setStore(
+          "todos",
+          produce((todos) => {
+            delete todos[oldID]
+          }),
+        )
+        setStore(
+          "agentSelections",
+          produce((selections) => {
+            delete selections[oldID]
+          }),
+        )
+        setPages(
+          produce((map) => {
+            delete map[oldID]
+          }),
+        )
+        setLoaded((prev) => {
+          if (!prev.has(oldID)) return prev
+          const next = new Set(prev)
+          next.delete(oldID)
+          return next
+        })
+      })
+    }
     setCurrentSessionID(id)
     setDraftSessionID(id)
     setLoading(!ready)