Migration error handling

packages/kilo-vscode/src/kilo-provider/handlers/migration.ts

@@ -114,15 +114,13 @@ export async function handleStartLegacyMigration(
       ctx.cachedLegacyData?.settings,
     )
 
-    // Dispose all instances after migration
-    // Reloading the data will be handled once the server replies with a global.disposed event
-    await ctx.disposeGlobal()
-
-    // Only mark as completed if at least one item succeeded — if everything failed
-    // the user can still re-run migration via Settings → About.
+    const failed = results.some((r) => r.status === "error")
     const success = results.some((r) => r.status === "success")
 
-    if (success) {
+    if (!failed && success) {
+      // Dispose all instances after a fully successful migration.
+      // Reloading the data will be handled once the server replies with a global.disposed event.
+      await ctx.disposeGlobal()
       await MigrationService.setMigrationStatus(
         ctx.extensionContext as Parameters<typeof MigrationService.setMigrationStatus>[0],
         "completed",

packages/kilo-vscode/src/legacy-migration/errors/migration-error.ts

@@ -0,0 +1,83 @@
+interface ErrorLike {
+  message?: unknown
+  status?: unknown
+  data?: unknown
+  body?: unknown
+}
+
+function isObject(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null
+}
+
+function getText(value: unknown): string | undefined {
+  if (typeof value === "string") {
+    const text = value.trim()
+    return text || undefined
+  }
+
+  if (typeof value === "number" || typeof value === "boolean") {
+    return String(value)
+  }
+
+  return undefined
+}
+
+function getMessage(value: unknown) {
+  if (!isObject(value)) return undefined
+  return getText((value as ErrorLike).message)
+}
+
+function getStatus(value: unknown) {
+  if (!isObject(value)) return undefined
+  const status = (value as ErrorLike).status
+  return typeof status === "number" ? String(status) : getText(status)
+}
+
+function getBody(value: unknown) {
+  if (!isObject(value)) return undefined
+
+  const body = (value as ErrorLike).body
+  const text = getText(body)
+  if (text) return text
+
+  if (isObject(body)) {
+    const msg = getMessage(body)
+    if (msg) return msg
+  }
+
+  return undefined
+}
+
+function getData(value: unknown) {
+  if (!isObject(value)) return undefined
+
+  const data = (value as ErrorLike).data
+  const text = getText(data)
+  if (text) return text
+
+  if (isObject(data)) {
+    const msg = getMessage(data)
+    if (msg) return msg
+  }
+
+  return undefined
+}
+
+export function getMigrationErrorMessage(err: unknown) {
+  const message = getMessage(err)
+  if (message) return message
+
+  const body = getBody(err)
+  if (body) return body
+
+  const data = getData(err)
+  if (data) return data
+
+  const status = getStatus(err)
+  if (status) return `Request failed (${status})`
+
+  const text = getText(err)
+  if (text) return text
+
+  return "Unknown migration error"
+}

packages/kilo-vscode/src/legacy-migration/legacy-types.ts

@@ -323,10 +323,3 @@ export interface MigrationSelections {
   defaultModel: boolean
   settings: MigrationSettingsSelections
 }
-
-export interface MigrationResultItem {
-  item: string
-  category: "provider" | "mcpServer" | "customMode" | "defaultModel" | "settings" | "session"
-  status: "success" | "warning" | "error"
-  message?: string
-}

packages/kilo-vscode/src/legacy-migration/migration-service.ts

@@ -16,6 +16,7 @@ import type {
 } from "@kilocode/sdk/v2/client"
 import { PROVIDER_MAP, UNSUPPORTED_PROVIDERS, DEFAULT_MODE_SLUGS } from "./provider-mapping"
 import type { ProviderMapping } from "./provider-mapping"
+import { getMigrationErrorMessage } from "./errors/migration-error"
 import type {
   LegacyProviderProfiles,
   LegacyProviderSettings,
@@ -30,8 +31,9 @@ import type {
   MigrationProviderInfo,
   MigrationMcpServerInfo,
   MigrationCustomModeInfo,
-  MigrationResultItem,
 } from "./legacy-types"
+import type { MigrationResultItem } from "./migration-types"
+import { createSessionID } from "./sessions/lib/ids"
 import { migrate as migrateSession } from "./sessions/migrate"
 
 // ---------------------------------------------------------------------------
@@ -214,17 +216,14 @@ export async function migrate(
     for (const id of selections.sessions) {
       onProgress("Chat sessions", "migrating")
       const result = await migrateSession(id, context, client)
+      const reason = result.ok ? "Session migrated" : result.message
       results.push({
         item: id,
         category: "session",
         status: result.ok ? "success" : "error",
-        message: result.ok ? "Session migrated" : "Session migration failed",
+        message: reason,
       })
-      onProgress(
-        "Chat sessions",
-        result.ok ? "success" : "error",
-        result.ok ? "Session migrated" : "Session migration failed",
-      )
+      onProgress("Chat sessions", result.ok ? "success" : "error", reason)
     }
   }
 
@@ -666,7 +665,7 @@ async function migrateAutocomplete(settings: LegacyAutocompleteSettings): Promis
       item: "Autocomplete settings",
       category: "settings",
       status: "error",
-      message: err instanceof Error ? err.message : String(err),
+      message: getMigrationErrorMessage(err),
     }
   }
 }
@@ -714,7 +713,7 @@ async function migrateLanguage(language: string): Promise<MigrationResultItem> {
       item: "Language preference",
       category: "settings",
       status: "error",
-      message: err instanceof Error ? err.message : String(err),
+      message: getMigrationErrorMessage(err),
     }
   }
 }

packages/kilo-vscode/src/legacy-migration/migration-types.ts

@@ -0,0 +1,6 @@
+export interface MigrationResultItem {
+  item: string
+  category: "provider" | "mcpServer" | "customMode" | "defaultModel" | "settings" | "session"
+  status: "success" | "warning" | "error"
+  message?: string
+}

packages/kilo-vscode/src/legacy-migration/sessions/migrate.ts

@@ -1,9 +1,22 @@
 import * as vscode from "vscode"
 import type { KiloClient } from "@kilocode/sdk/v2/client"
+import { getMigrationErrorMessage } from "../errors/migration-error"
 import type { LegacyHistoryItem } from "./lib/legacy-types"
 import { parseSession } from "./parser"
 
-export async function migrate(id: string, context: vscode.ExtensionContext, client: KiloClient) {
+type Result =
+  | {
+      ok: true
+      skipped?: boolean
+      payload: Awaited<ReturnType<typeof parseSession>>
+    }
+  | {
+      ok: false
+      payload: Awaited<ReturnType<typeof parseSession>>
+      message: string
+    }
+
+export async function migrate(id: string, context: vscode.ExtensionContext, client: KiloClient): Promise<Result> {
   const dir = vscode.Uri.joinPath(context.globalStorageUri, "tasks").fsPath
   const items = context.globalState.get<LegacyHistoryItem[]>("taskHistory", [])
   const item = items.find((item) => item.id === id)
@@ -46,7 +59,7 @@ export async function migrate(id: string, context: vscode.ExtensionContext, clie
     return {
       ok: false,
       payload,
-      error,
+      message: getMigrationErrorMessage(error),
     }
   }
 }

packages/kilo-vscode/webview-ui/src/components/migration/MigrationWizard.tsx

@@ -8,6 +8,7 @@
 
 import { Show, createSignal, onMount, onCleanup } from "solid-js"
 import type { Component, JSX } from "solid-js"
+import { showToast } from "@kilocode/kilo-ui/toast"
 import { useVSCode } from "../../context/vscode"
 import { useLanguage } from "../../context/language"
 import type {
@@ -154,7 +155,7 @@ const WarningSvg = (): JSX.Element => (
 // ---------------------------------------------------------------------------
 
 type Screen = "whats-new" | "migrate"
-type MigratePhase = "selecting" | "migrating" | "done"
+type MigratePhase = "selecting" | "migrating" | "error" | "done"
 
 interface ProgressEntry {
   item: string
@@ -263,7 +264,11 @@ const MigrationWizard: Component<MigrationWizardProps> = (props) => {
       if (msg?.type === "legacyMigrationComplete") {
         const complete = msg as LegacyMigrationCompleteMessage
         setResults(complete.results)
-        setPhase("done")
+        const hasErrors = complete.results.some((r) => r.status === "error")
+        setPhase(hasErrors ? "error" : "done")
+        if (!hasErrors) {
+          vscode.postMessage({ type: "loadSessions" })
+        }
       }
     }
 
@@ -382,6 +387,11 @@ const MigrationWizard: Component<MigrationWizardProps> = (props) => {
     props.onComplete()
   }
 
+  const copySessionError = async (text: string) => {
+    await navigator.clipboard.writeText(text)
+    showToast({ variant: "success", title: language.t("migration.error.toast.copied") })
+  }
+
   // ---------------------------------------------------------------------------
   // Data helpers
   // ---------------------------------------------------------------------------
@@ -431,17 +441,19 @@ const MigrationWizard: Component<MigrationWizardProps> = (props) => {
 
   // Group-level status for progress display
   const groupStatus = (group: string): ProgressEntry["status"] => {
-    const entries = progressEntries().filter((e) => e.group === group)
+    const entries = progressEntries().filter((entry) => entry.group === group)
     if (entries.length === 0) return "pending"
-    if (entries.some((e) => e.status === "error")) return "error"
-    if (entries.some((e) => e.status === "warning")) return "warning"
-    if (entries.every((e) => e.status === "success")) return "success"
-    if (entries.some((e) => e.status === "migrating")) return "migrating"
+    if (entries.some((entry) => entry.status === "error")) return "error"
+    if (entries.some((entry) => entry.status === "warning")) return "warning"
+    if (entries.every((entry) => entry.status === "success")) return "success"
+    if (entries.some((entry) => entry.status === "migrating")) return "migrating"
     return "pending"
   }
 
-  const successCount = () => results().filter((r) => r.status === "success").length
+  const successCount = () => results().filter((result) => result.status === "success").length
   const totalCount = () => results().length
+  const groupMessage = (group: string) =>
+    progressEntries().find((entry) => entry.group === group && entry.status === "error")?.message
 
   // ---------------------------------------------------------------------------
   // Status icon renderer
@@ -677,8 +689,33 @@ const MigrationWizard: Component<MigrationWizardProps> = (props) => {
                     </label>
                   </Show>
                   <div class="migration-wizard__item-text">
-                    <div class="label">Chat Sessions &amp; History</div>
-                    <div class="desc">{sessions().length} sessions detected</div>
+                    <div class="label">{language.t("migration.migrate.chatHistory")}</div>
+                    <div class="desc">
+                      {language.t("migration.migrate.sessionsDetected", { count: String(sessions().length) })}
+                    </div>
+                    <Show
+                      when={
+                        (phase() === "error" || phase() === "done") &&
+                        groupStatus("sessions") === "error" &&
+                        groupMessage("sessions")
+                      }
+                    >
+                      <div class="migration-wizard__error-box">
+                        <div class="migration-wizard__error-box-header">
+                          <div class="migration-wizard__error-box-title">
+                            {language.t("migration.error.sessionFailed")}
+                          </div>
+                          <button
+                            type="button"
+                            class="migration-wizard__copy-btn"
+                            onClick={() => void copySessionError(groupMessage("sessions")!)}
+                          >
+                            {language.t("migration.error.action.copy")}
+                          </button>
+                        </div>
+                        <div class="migration-wizard__error-text">{groupMessage("sessions")}</div>
+                      </div>
+                    </Show>
                   </div>
                 </div>
               </Show>
@@ -768,6 +805,7 @@ const MigrationWizard: Component<MigrationWizardProps> = (props) => {
               </Show>
 
               {/* Cleanup option after done */}
+              {/*
               <Show when={phase() === "done"}>
                 <div class="migration-wizard__divider" />
                 <div class="migration-wizard__item migration-wizard__item--clickable">
@@ -787,6 +825,7 @@ const MigrationWizard: Component<MigrationWizardProps> = (props) => {
                   </div>
                 </div>
               </Show>
+              */}
             </div>
           </Show>
 
@@ -818,6 +857,18 @@ const MigrationWizard: Component<MigrationWizardProps> = (props) => {
                   {language.t("migration.migrate.button")}
                 </button>
               </Show>
+              <Show when={phase() === "error"}>
+                <button
+                  type="button"
+                  class="migration-wizard__btn migration-wizard__btn--primary"
+                  onClick={() => {
+                    vscode.postMessage({ type: "loadSessions" })
+                    setPhase("done")
+                  }}
+                >
+                  {language.t("migration.error.continue")}
+                </button>
+              </Show>
               <Show when={phase() === "done"}>
                 <button type="button" class="migration-wizard__btn migration-wizard__btn--primary" onClick={handleDone}>
                   {language.t("migration.complete.done")}