refactor(session): centralize fallback title policy (#39890)

packages/tui/src/app.tsx

@@ -76,7 +76,7 @@ import { PromptHistoryProvider } from "./component/prompt/history"
 import { FrecencyProvider } from "./component/prompt/frecency"
 import { PromptStashProvider } from "./component/prompt/stash"
 import { Toast, ToastProvider, useToast } from "./ui/toast"
-import { isDefaultTitle } from "./util/session"
+import { isFallbackTitle } from "@opencode-ai/util/session-title-fallback"
 import * as Model from "./util/model"
 import { ArgsProvider, useArgs, type Args } from "./context/args"
 import open from "open"
@@ -537,7 +537,7 @@ function App(props: { pair?: DialogPairCredentials }) {
 
     if (route.data.type === "session") {
       const title = session?.title
-      if (!title || isDefaultTitle(title)) {
+      if (!title || isFallbackTitle(title)) {
         renderer.setTerminalTitle("OpenCode")
         return
       }

packages/tui/src/component/dialog-open.tsx

@@ -16,7 +16,7 @@ import { abbreviateHome } from "../runtime"
 import { useTuiPaths } from "../context/runtime"
 import { truncateFilePath } from "../ui/file-path"
 import { stringWidth } from "../util/string-width"
-import { sessionTitle } from "../util/session"
+import { withTimestampedFallback } from "@opencode-ai/util/session-title-fallback"
 import { Spinner } from "./spinner"
 
 const RECENT_LIMIT = 8
@@ -80,7 +80,7 @@ export function DialogOpen() {
       const name = project?.canonical === "/" ? undefined : project?.name || path.basename(project?.canonical ?? "")
       const running = data.session.family(session.id).some((id) => data.session.status(id) === "running")
       return {
-        title: sessionTitle(session),
+        title: withTimestampedFallback(session),
         value: { type: "session", sessionID: session.id } as OpenTarget,
         category: "Sessions",
         footer: `${name ? `${Locale.truncate(name, 20)} · ` : ""}${timeAgo(session.time.updated)}`,

packages/tui/src/component/dialog-session-list.tsx

@@ -18,8 +18,8 @@ import { Spinner } from "./spinner"
 import { errorMessage } from "../util/error"
 import { useSessionTabs } from "../context/session-tabs"
 import { useStorage } from "../context/storage"
-import { sessionTitle } from "../util/session"
 import { useConfig } from "../config"
+import { withTimestampedFallback } from "@opencode-ai/util/session-title-fallback"
 
 export function DialogSessionList() {
   const dialog = useDialog()
@@ -82,7 +82,9 @@ export function DialogSessionList() {
           (session.projectID === current?.project.id && session.location.directory === current.directory),
       )
     if (!query) return sessions
-    return sessions.filter((session) => !session.parentID && sessionTitle(session).toLowerCase().includes(query))
+    return sessions.filter(
+      (session) => !session.parentID && withTimestampedFallback(session).toLowerCase().includes(query),
+    )
   })
   const sessions = createMemo(() => {
     const query = filter().trim()
@@ -144,7 +146,9 @@ export function DialogSessionList() {
       const slot = sessionTabs.enabled() ? undefined : slotByID.get(session.id)
       const deleting = toDelete() === session.id
       return {
-        title: deleting ? `Press ${shortcuts.get("session.delete")} again to confirm` : sessionTitle(session),
+        title: deleting
+          ? `Press ${shortcuts.get("session.delete")} again to confirm`
+          : withTimestampedFallback(session),
         value: session.id,
         category,
         footer,

packages/tui/src/context/session-tabs.tsx

@@ -3,7 +3,7 @@ import { isDeepEqual } from "remeda"
 import { createSimpleContext } from "./helper"
 import { useClient } from "./client"
 import { useData } from "./data"
-import { sessionTitle } from "../util/session"
+import { withTimestampedFallback } from "@opencode-ai/util/session-title-fallback"
 import { useEvent } from "./event"
 import { useRoute } from "./route"
 import { useConfig } from "../config"
@@ -116,7 +116,8 @@ export const { use: useSessionTabs, provider: SessionTabsProvider } = createSimp
       const sessionID = root(route.data.sessionID)
       history = recordSessionTabHistory(history, sessionID)
       const session = data.session.get(sessionID)
-      const title = session?.title ?? (newTab() ? NEW_SESSION_TAB_TITLE : session ? sessionTitle(session) : undefined)
+      const title =
+        session?.title ?? (newTab() ? NEW_SESSION_TAB_TITLE : session ? withTimestampedFallback(session) : undefined)
       const tabs = openSessionTab(state().tabs, { sessionID, title })
       if (tabs === state().tabs && !state().unread[sessionID]) return
       update((draft) => {
@@ -130,7 +131,10 @@ export const { use: useSessionTabs, provider: SessionTabsProvider } = createSimp
       const next = state().tabs.reduce<SessionTab[]>((tabs, tab) => {
         const sessionID = root(tab.sessionID)
         const session = data.session.get(sessionID)
-        return openSessionTab(tabs, { sessionID, title: session ? sessionTitle(session) : tab.title })
+        return openSessionTab(tabs, {
+          sessionID,
+          title: session ? withTimestampedFallback(session) : tab.title,
+        })
       }, [])
       const unread = Object.entries(state().unread).reduce<Record<string, SessionTabUnread>>((result, entry) => {
         const sessionID = root(entry[0])

packages/tui/src/mini/runtime.lifecycle.ts

@@ -10,7 +10,7 @@
 // back to the usual two-press exit sequence through RunFooter.requestExit().
 import path from "path"
 import { CliRenderEvents, createCliRenderer, type CliRenderer, type ScrollbackWriter } from "@opentui/core"
-import { isDefaultTitle } from "../util/session"
+import { isFallbackTitle } from "@opencode-ai/util/session-title-fallback"
 import { monoSnapshot } from "./mono"
 import { entrySplash, exitSplash, splashMeta } from "./splash"
 import { resolveRunTheme } from "./theme"
@@ -105,7 +105,7 @@ function shutdown(renderer: CliRenderer): void {
 }
 
 function splashInfo(title: string | undefined, history: RunPrompt[]) {
-  if (title && !isDefaultTitle(title)) {
+  if (title && !isFallbackTitle(title)) {
     return {
       title,
       showSession: true,
@@ -176,7 +176,7 @@ export async function createRuntimeLifecycle(input: LifecycleInput): Promise<Lif
   if (mono) renderer.on(CliRenderEvents.EXTERNAL_OUTPUT, monoSnapshot)
   const setTitle = (title?: string) => {
     if (input.host.platform !== "linux") return
-    if (!title || isDefaultTitle(title)) return renderer.setTerminalTitle("OpenCode")
+    if (!title || isFallbackTitle(title)) return renderer.setTerminalTitle("OpenCode")
     renderer.setTerminalTitle(`OC | ${title.length > 40 ? title.slice(0, 37) + "..." : title}`)
   }
   setTitle(input.sessionTitle)

packages/tui/src/routes/session/composer/subagents-tab.tsx

@@ -8,7 +8,7 @@ import { useTheme } from "../../../context/theme"
 import { Locale } from "../../../util/locale"
 import { Keymap } from "../../../context/keymap"
 import { useComposerTab } from "./index"
-import { sessionTitle } from "../../../util/session"
+import { withTimestampedFallback } from "@opencode-ai/util/session-title-fallback"
 
 interface SubagentEntry {
   sessionID: string
@@ -39,7 +39,7 @@ export function SubagentsTab(props: { sessionID: string }) {
     if (current.parentID) {
       const siblings = data.session.list().filter((s) => s.parentID === current.parentID)
       for (const sibling of siblings) {
-        const title = sessionTitle(sibling)
+        const title = withTimestampedFallback(sibling)
         const agentMatch = title.match(/@(\w+) subagent/)
         const agent = sibling.agent
           ? Locale.titlecase(sibling.agent)
@@ -58,7 +58,7 @@ export function SubagentsTab(props: { sessionID: string }) {
     } else {
       const children = data.session.list().filter((s) => s.parentID === props.sessionID)
       for (const child of children) {
-        const title = sessionTitle(child)
+        const title = withTimestampedFallback(child)
         const agentMatch = title.match(/@(\w+) subagent/)
         const agent = child.agent
           ? Locale.titlecase(child.agent)

packages/tui/src/routes/session/index.tsx

@@ -92,7 +92,7 @@ import { switchLabel } from "../../util/model"
 import { findMessageBoundary, messageNavigationSlack } from "./message-navigation"
 import { stringWidth } from "../../util/string-width"
 import { useArgs } from "../../context/args"
-import { sessionTitle } from "../../util/session"
+import { withTimestampedFallback } from "@opencode-ai/util/session-title-fallback"
 
 addDefaultParsers(parsers.parsers)
 
@@ -3308,7 +3308,7 @@ function formatSessionTranscript(session: SessionInfo, messages: SessionMessageI
     })
     return [`## Assistant\n\n${content.join("\n\n")}`]
   })
-  return `# ${sessionTitle(session)}\n\n**Session ID:** ${session.id}\n**Created:** ${new Date(session.time.created).toLocaleString()}\n**Updated:** ${new Date(session.time.updated).toLocaleString()}\n\n---\n\n${body.join("\n\n---\n\n")}\n`
+  return `# ${withTimestampedFallback(session)}\n\n**Session ID:** ${session.id}\n**Created:** ${new Date(session.time.created).toLocaleString()}\n**Updated:** ${new Date(session.time.updated).toLocaleString()}\n\n---\n\n${body.join("\n\n---\n\n")}\n`
 }
 
 export function parseApplyPatchFiles(value: unknown) {

packages/tui/src/routes/session/sidebar.tsx

@@ -3,7 +3,7 @@ import { createMemo, Show } from "solid-js"
 import { useTheme } from "../../context/theme"
 import { useConfig } from "../../config"
 import { PluginSlot } from "../../plugin/context"
-import { sessionTitle } from "../../util/session"
+import { withTimestampedFallback } from "@opencode-ai/util/session-title-fallback"
 
 import { getScrollAcceleration } from "../../util/scroll"
 
@@ -39,7 +39,7 @@ export function Sidebar(props: { sessionID: string; overlay?: boolean }) {
           <box flexShrink={0} gap={1} paddingRight={1}>
             <box paddingRight={1}>
               <text fg={theme.text.default}>
-                <b>{sessionTitle(session()!)}</b>
+                <b>{withTimestampedFallback(session()!)}</b>
               </text>
               <Show when={session()!.location.workspaceID}>
                 <text fg={theme.text.subdued}>{session()!.location.workspaceID}</text>

packages/tui/src/util/session.ts

@@ -1,18 +1,6 @@
-import type { ModelInfo, SessionInfo, SessionMessageAssistant, SessionMessageInfo } from "@opencode-ai/client"
+import type { ModelInfo, SessionMessageAssistant, SessionMessageInfo } from "@opencode-ai/client"
 import { Locale } from "./locale"
 
-export function isDefaultTitle(title?: string) {
-  return (
-    title === undefined || /^(New session - |Child session - )\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}Z$/.test(title)
-  )
-}
-
-export function sessionTitle(session: Pick<SessionInfo, "parentID" | "time" | "title">) {
-  return (
-    session.title ?? `${session.parentID ? "Child" : "New"} session - ${new Date(session.time.created).toISOString()}`
-  )
-}
-
 export function lastAssistantWithUsage(messages: ReadonlyArray<SessionMessageInfo>, boundary?: string) {
   const boundaryIndex = boundary ? messages.findIndex((message) => message.id === boundary) : -1
   if (boundary && boundaryIndex === -1) return undefined

packages/tui/test/util/session.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import type { SessionMessageInfo } from "@opencode-ai/client"
-import { isDefaultTitle, lastAssistantWithUsage, sessionTitle } from "../../src/util/session"
+import { lastAssistantWithUsage } from "../../src/util/session"
 
 const assistant = (id: string, input: number): SessionMessageInfo => ({
   id,
@@ -13,22 +13,6 @@ const assistant = (id: string, input: number): SessionMessageInfo => ({
 })
 
 describe("util.session", () => {
-  test("recognizes generated parent and child titles", () => {
-    expect(isDefaultTitle(undefined)).toBeTrue()
-    expect(isDefaultTitle("New session - 2026-06-06T12:34:56.789Z")).toBeTrue()
-    expect(isDefaultTitle("Child session - 2026-06-06T12:34:56.789Z")).toBeTrue()
-    expect(isDefaultTitle("New session - custom")).toBeFalse()
-  })
-
-  test("derives display-only titles for untitled sessions", () => {
-    expect(sessionTitle({ title: undefined, time: { created: 0, updated: 0 } })).toBe(
-      "New session - 1970-01-01T00:00:00.000Z",
-    )
-    expect(sessionTitle({ title: undefined, parentID: "ses_parent", time: { created: 0, updated: 0 } })).toBe(
-      "Child session - 1970-01-01T00:00:00.000Z",
-    )
-  })
-
   test("tracks usage across undo and redo boundaries", () => {
     const messages = [assistant("msg_z", 10), assistant("msg_a", 30)]