Clarify thread title semantics

src/domain/threads/archive-markdown.ts

@@ -1,6 +1,6 @@
 import type { Thread } from "./model";
 import { referencedThreadMetadataFromPrompt } from "./reference";
-import { threadUserTitle } from "./title";
+import { threadArchiveTitle } from "./title";
 import type { ThreadTranscriptEntry } from "./transcript";
 
 interface ParsedMarkdownLink {
@@ -51,7 +51,7 @@ export function archivedThreadMarkdown(
 }
 
 export function archivedThreadTitle(thread: ArchiveThreadInput): string {
-  return threadUserTitle(thread) || "Untitled thread";
+  return threadArchiveTitle(thread);
 }
 
 function normalizeExportedMarkdownLinks(markdown: string, vaultPath: string): string {

src/domain/threads/model.ts

@@ -7,13 +7,6 @@ export interface Thread {
   readonly updatedAt: number;
 }
 
-export function getThreadTitle(thread: Thread): string {
-  return (
-    [thread.name, thread.preview, thread.id].map((value) => (typeof value === "string" ? normalizeTitle(value) : "")).find(Boolean) ??
-    thread.id
-  );
-}
-
 export function explicitThreadName(thread: Thread): string | null {
   return normalizeExplicitThreadName(thread.name);
 }

src/domain/threads/reference.ts

@@ -1,5 +1,5 @@
 import type { Thread } from "./model";
-import { threadUserTitle } from "./title";
+import { threadDisplayTitle } from "./title";
 import type { ThreadConversationSummary } from "./transcript";
 
 export const REFERENCED_THREAD_TURN_LIMIT = 20;
@@ -48,7 +48,7 @@ function referencedThreadPrompt(thread: Thread, turns: readonly ThreadConversati
 function referencedThreadMetadata(thread: Thread, count: number): ReferencedThreadMetadata {
   return {
     threadId: thread.id,
-    title: threadUserTitle(thread),
+    title: threadDisplayTitle(thread),
     includedTurns: count,
     turnLimit: REFERENCED_THREAD_TURN_LIMIT,
   };

src/domain/threads/title.ts

@@ -1,39 +1,48 @@
 import { shortThreadId } from "../../utils";
-import { getThreadTitle, type Thread } from "./model";
+import type { Thread } from "./model";
 
 const MAX_ARCHIVED_THREAD_DISPLAY_TITLE_LENGTH = 96;
+const UNTITLED_THREAD_TITLE = "Untitled thread";
 const UUID_PATTERN = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i;
 
-export function threadUserTitle(thread: Thread): string {
-  return usefulThreadTitle(thread) ?? getThreadTitle(thread);
+export function threadMeaningfulTitle(thread: Thread): string | null {
+  for (const value of [thread.name, thread.preview]) {
+    const title = normalizeThreadTitleText(value);
+    if (title && title !== thread.id && !UUID_PATTERN.test(title)) return title;
+  }
+  return null;
+}
+
+export function threadDisplayTitle(thread: Thread): string {
+  return threadMeaningfulTitle(thread) ?? UNTITLED_THREAD_TITLE;
 }
 
 export function threadRenameDraftTitle(thread: Thread): string {
-  return usefulThreadTitle(thread) ?? "";
+  return threadMeaningfulTitle(thread) ?? "";
+}
+
+export function threadArchiveTitle(thread: Thread): string {
+  return threadMeaningfulTitle(thread) ?? UNTITLED_THREAD_TITLE;
 }
 
 export function threadArchiveDisplayTitle(thread: Thread): string {
-  const title = usefulThreadTitle(thread);
-  return title ? truncateThreadTitle(title, MAX_ARCHIVED_THREAD_DISPLAY_TITLE_LENGTH) : "Untitled archived thread";
+  return truncateThreadTitle(threadArchiveTitle(thread), MAX_ARCHIVED_THREAD_DISPLAY_TITLE_LENGTH);
 }
 
 export function threadWindowTitle(activeThreadId: string | null, threads: readonly Thread[], fallbackTitle?: string | null): string {
   if (!activeThreadId) return "Codex";
 
   const thread = threads.find((item) => item.id === activeThreadId);
-  const title = thread ? threadUserTitle(thread) : normalizeTitle(fallbackTitle) || shortThreadId(activeThreadId);
+  const restoredTitle = normalizeThreadTitleText(fallbackTitle);
+  const title = thread
+    ? (threadMeaningfulTitle(thread) ?? shortThreadId(thread.id))
+    : restoredTitle.length > 0
+      ? restoredTitle
+      : shortThreadId(activeThreadId);
   return title ? `Codex: ${title}` : "Codex";
 }
 
-function usefulThreadTitle(thread: Thread): string | null {
-  for (const value of [thread.name, thread.preview]) {
-    const title = normalizeTitle(value);
-    if (title && title !== thread.id && !UUID_PATTERN.test(title)) return title;
-  }
-  return null;
-}
-
-function normalizeTitle(value: string | null | undefined): string {
+function normalizeThreadTitleText(value: string | null | undefined): string {
   return typeof value === "string" ? value.replace(/\s+/g, " ").trim() : "";
 }
 

src/features/chat/application/composer/suggestions.ts

@@ -4,7 +4,7 @@ import { prepareFuzzySearch, sortSearchResults, type SearchResult } from "obsidi
 import { findModelMetadataByIdOrName, sortedModelMetadata } from "../../../../domain/catalog/metadata";
 import { supportedEffortsForModelMetadata } from "../../../../domain/catalog/metadata";
 import { SLASH_COMMANDS, slashCommandSubcommands, type SlashCommandName } from "./slash-commands";
-import { threadUserTitle } from "../../../../domain/threads/title";
+import { threadDisplayTitle } from "../../../../domain/threads/title";
 import { shortThreadId } from "../../../../utils";
 
 export interface ComposerSuggestion {
@@ -277,7 +277,7 @@ function activeThreadCommandSuggestions(beforeCursor: string, threads: readonly
   if (threads.some((thread) => thread.id.toLowerCase() === query)) return null;
   return threads
     .map((thread, index) => {
-      const title = threadUserTitle(thread);
+      const title = threadDisplayTitle(thread);
       const id = thread.id.toLowerCase();
       const normalizedTitle = title.toLowerCase();
       const score = query.length === 0 ? 2 : id.startsWith(query) ? 0 : normalizedTitle.includes(query) ? 1 : id.includes(query) ? 2 : -1;

src/features/chat/application/conversation/slash-command-execution.ts

@@ -3,8 +3,9 @@ import type { ThreadGoal } from "../../../../domain/threads/goal";
 import type { ReasoningEffort } from "../../../../domain/catalog/metadata";
 import { normalizeReasoningEffort } from "../../../../domain/catalog/metadata";
 import type { Thread } from "../../../../domain/threads/model";
-import { threadUserTitle } from "../../../../domain/threads/title";
+import { threadDisplayTitle } from "../../../../domain/threads/title";
 import type { ReferencedThreadMetadata } from "../../../../domain/threads/reference";
+import { shortThreadId } from "../../../../utils";
 import type { ChatRuntimeSettingsActions } from "../runtime/settings-actions";
 import type { GoalActions } from "../threads/goal-actions";
 import type { ThreadManagementActions } from "../threads/thread-management-actions";
@@ -463,9 +464,15 @@ function resolveThreadArgument(args: string, threads: readonly Thread[]): Thread
   if (idMatches.length > 1) return { ok: false, message: `Multiple matching threads: ${idMatches.map((thread) => thread.id).join(", ")}` };
 
   const titleQuery = query.toLowerCase();
-  const titleMatches = threads.filter((thread) => threadUserTitle(thread).toLowerCase().includes(titleQuery));
+  const titleMatches = threads.filter((thread) => threadDisplayTitle(thread).toLowerCase().includes(titleQuery));
   if (titleMatches.length === 1 && titleMatches[0]) return { ok: true, thread: titleMatches[0] };
-  if (titleMatches.length > 1) return { ok: false, message: `Multiple matching threads: ${titleMatches.map(threadUserTitle).join(", ")}` };
+  if (titleMatches.length > 1) {
+    return { ok: false, message: `Multiple matching threads: ${titleMatches.map(threadResolutionLabel).join(", ")}` };
+  }
 
   return { ok: false, message: `No matching thread: ${query}` };
 }
+
+function threadResolutionLabel(thread: Thread): string {
+  return `${threadDisplayTitle(thread)} (${shortThreadId(thread.id)})`;
+}

src/features/chat/host/session.ts

@@ -1,7 +1,7 @@
 import type { AppServerClient } from "../../../app-server/connection/client";
 import { appServerQueryContextRawEquals, type AppServerQueryContext } from "../../../app-server/query/keys";
 
-import { threadUserTitle, threadWindowTitle } from "../../../domain/threads/title";
+import { threadMeaningfulTitle, threadWindowTitle } from "../../../domain/threads/title";
 import { ConnectionWorkTracker } from "../../../shared/lifecycle/connection-work";
 import { createChatViewDeferredTasks } from "./lifecycle";
 import { ChatResumeWorkTracker, type ChatViewDeferredTasks } from "../application/lifecycle";
@@ -225,7 +225,7 @@ export class ChatPanelSession implements ChatSurfaceHandle {
     const threadId = this.state.activeThread.id;
     if (!threadId) return null;
     const thread = this.state.threadList.listedThreads.find((item) => item.id === threadId);
-    return thread ? threadUserTitle(thread) : null;
+    return thread ? threadMeaningfulTitle(thread) : null;
   }
 
   private restoredThreadTitle(): string | null {

src/features/chat/panel/surface/toolbar-projection.tsx

@@ -2,7 +2,7 @@ import type { ComponentChild as UiNode } from "preact";
 import { h } from "preact";
 
 import type { Thread } from "../../../../domain/threads/model";
-import { threadUserTitle } from "../../../../domain/threads/title";
+import { threadDisplayTitle } from "../../../../domain/threads/title";
 import { rateLimitSummary } from "../../presentation/runtime/status";
 import { connectionDiagnosticSectionsModel } from "../../application/connection/diagnostics-display";
 import { toolInventoryDiagnosticSections } from "../../application/connection/tool-inventory-display";
@@ -135,7 +135,7 @@ function toolbarThreadRows(input: {
   return input.threads.map((thread) => {
     const threadId = thread.id;
     return {
-      title: threadUserTitle(thread),
+      title: threadDisplayTitle(thread),
       threadId,
       selected: threadId === input.activeThreadId,
       disabled: input.turnBusy && threadId !== input.activeThreadId,

src/features/thread-picker/modal.ts

@@ -1,7 +1,7 @@
 import { Notice, Platform, SuggestModal, type App } from "obsidian";
 
 import type { Thread } from "../../domain/threads/model";
-import { threadUserTitle } from "../../domain/threads/title";
+import { threadDisplayTitle } from "../../domain/threads/title";
 import { shortThreadId } from "../../utils";
 import type { ThreadCatalogActiveReader } from "../../workspace/thread-catalog";
 
@@ -39,7 +39,7 @@ function threadPickerSuggestions(threads: readonly Thread[], queryText: string):
   return [...threads]
     .sort((a, b) => b.updatedAt - a.updatedAt)
     .map((thread, index) => {
-      const title = threadUserTitle(thread);
+      const title = threadDisplayTitle(thread);
       const id = thread.id.toLowerCase();
       const normalizedTitle = title.toLowerCase();
       const shortId = shortThreadId(thread.id).toLowerCase();
@@ -106,6 +106,7 @@ class ThreadPickerModal extends SuggestModal<ThreadSuggestion> {
   override renderSuggestion(value: ThreadSuggestion, el: HTMLElement): void {
     const contentEl = el.createDiv({ cls: "suggestion-content" });
     contentEl.createDiv({ cls: "suggestion-title", text: value.title });
+    el.createDiv({ cls: "suggestion-note", text: shortThreadId(value.thread.id) });
   }
 
   override onChooseSuggestion(item: ThreadSuggestion, evt: MouseEvent | KeyboardEvent): void {

src/features/threads-view/renderer.tsx

@@ -123,7 +123,7 @@ function ThreadRow({ row, actions }: { row: ThreadsRowModel; actions: ThreadsVie
                 className="codex-panel-threads__row-button"
                 onClick={(event) => {
                   event.stopPropagation();
-                  actions.startRename(row.thread.id, row.thread.name ?? row.title);
+                  actions.startRename(row.thread.id, row.rename.draft);
                 }}
               />
             ) : null}

src/features/threads-view/state.ts

@@ -1,5 +1,5 @@
 import type { Thread } from "../../domain/threads/model";
-import { threadRenameDraftTitle, threadUserTitle } from "../../domain/threads/title";
+import { threadDisplayTitle, threadRenameDraftTitle } from "../../domain/threads/title";
 import type { OpenCodexPanelSnapshot } from "../../workspace/panel-coordinator";
 import {
   initialThreadRenameLifecycleState,
@@ -65,7 +65,7 @@ export function threadRows(
       const rename = renameStates.get(thread.id);
       return {
         thread,
-        title: threadUserTitle(thread),
+        title: threadDisplayTitle(thread),
         live,
         selected,
         rename: {

tests/domain/threads/archive-markdown.test.ts

@@ -50,6 +50,14 @@ describe("thread archive export", () => {
     expect(output).not.toContain("npm test");
   });
 
+  it("uses the shared archive title placeholder instead of leaking thread ids", () => {
+    const output = exportedMarkdown(thread({ name: null, preview: "" }), new Date(2026, 4, 18));
+
+    expect(output).toContain('title: "Untitled thread"');
+    expect(output).toContain("# Untitled thread");
+    expect(output).not.toContain("# 019e0182-cb70-7a72-ab48-8bc9d0b0d781");
+  });
+
   it("falls back when turn timestamps are missing and uses start time for incomplete agent output", () => {
     const output = exportedMarkdown(
       thread({

tests/domain/threads/threads.test.ts

@@ -2,27 +2,34 @@ import { describe, expect, it } from "vitest";
 
 import {
   explicitThreadName,
-  getThreadTitle,
   inheritedForkThreadName,
   normalizeExplicitThreadName,
   upsertThread,
   type Thread,
 } from "../../../src/domain/threads/model";
-import { threadArchiveDisplayTitle, threadRenameDraftTitle, threadUserTitle, threadWindowTitle } from "../../../src/domain/threads/title";
+import {
+  threadArchiveDisplayTitle,
+  threadArchiveTitle,
+  threadDisplayTitle,
+  threadMeaningfulTitle,
+  threadRenameDraftTitle,
+  threadWindowTitle,
+} from "../../../src/domain/threads/title";
 
 describe("thread helpers", () => {
-  it("resolves display titles from explicit names, previews, then ids", () => {
-    expect(getThreadTitle(thread({ name: "  Named   thread  ", preview: "Preview" }))).toBe("Named thread");
-    expect(getThreadTitle(thread({ name: "  ", preview: "  Preview   only  " }))).toBe("Preview only");
-    expect(getThreadTitle(thread({ id: "thread-id", name: null, preview: "" }))).toBe("thread-id");
+  it("resolves meaningful titles from explicit names, then previews, without id fallbacks", () => {
+    expect(threadMeaningfulTitle(thread({ name: "  Named   thread  ", preview: "Preview" }))).toBe("Named thread");
+    expect(threadMeaningfulTitle(thread({ name: "  ", preview: "  Preview   only  " }))).toBe("Preview only");
+    expect(threadMeaningfulTitle(thread({ id: "thread-id", name: null, preview: "" }))).toBeNull();
   });
 
-  it("keeps user-facing titles identifiable while keeping rename drafts human-authored", () => {
+  it("keeps user-facing placeholders separate from rename drafts and archive titles", () => {
     const idOnly = thread({ id: "019e0182-cb70-7a72-ab48-8bc9d0b0d781", name: null, preview: "" });
 
-    expect(threadUserTitle(idOnly)).toBe("019e0182-cb70-7a72-ab48-8bc9d0b0d781");
+    expect(threadDisplayTitle(idOnly)).toBe("Untitled thread");
     expect(threadRenameDraftTitle(idOnly)).toBe("");
-    expect(threadArchiveDisplayTitle(idOnly)).toBe("Untitled archived thread");
+    expect(threadArchiveTitle(idOnly)).toBe("Untitled thread");
+    expect(threadArchiveDisplayTitle(idOnly)).toBe("Untitled thread");
   });
 
   it("uses useful preview text instead of UUID-like names for draft and archive titles", () => {
@@ -32,8 +39,9 @@ describe("thread helpers", () => {
       preview: "  Useful   preview  ",
     });
 
-    expect(threadUserTitle(uuidNamed)).toBe("Useful preview");
+    expect(threadDisplayTitle(uuidNamed)).toBe("Useful preview");
     expect(threadRenameDraftTitle(uuidNamed)).toBe("Useful preview");
+    expect(threadArchiveTitle(uuidNamed)).toBe("Useful preview");
     expect(threadArchiveDisplayTitle(uuidNamed)).toBe("Useful preview");
   });
 
@@ -43,6 +51,7 @@ describe("thread helpers", () => {
     expect(threadWindowTitle(null, [])).toBe("Codex");
     expect(threadWindowTitle("thread", [thread({ id: "thread", name: "  Named   thread  " })])).toBe("Codex: Named thread");
     expect(threadWindowTitle("thread", [], "  Restored   title  ")).toBe("Codex: Restored title");
+    expect(threadWindowTitle(uuid, [thread({ id: uuid, name: null, preview: "" })])).toBe("Codex: 019e0182");
     expect(threadWindowTitle(uuid, [], null)).toBe("Codex: 019e0182");
   });
 

tests/features/chat/conversation/turns/slash-command-execution.test.ts

@@ -134,7 +134,7 @@ describe("slash commands", () => {
     await executeSlashCommand("resume", "Draft", ctx);
 
     expect(ctx.resumeThread).not.toHaveBeenCalled();
-    expect(ctx.addSystemMessage).toHaveBeenCalledWith("Multiple matching threads: Draft, Draft notes");
+    expect(ctx.addSystemMessage).toHaveBeenCalledWith("Multiple matching threads: Draft (thread-a), Draft notes (thread-b)");
   });
 
   it("returns referenced input for /refer", async () => {
@@ -428,7 +428,7 @@ describe("slash commands", () => {
     await executeSlashCommand("archive", "Draft", ctx);
 
     expect(ctx.threadActions.archiveThread).not.toHaveBeenCalled();
-    expect(ctx.addSystemMessage).toHaveBeenCalledWith("Multiple matching threads: Draft, Draft notes");
+    expect(ctx.addSystemMessage).toHaveBeenCalledWith("Multiple matching threads: Draft (thread-a), Draft notes (thread-b)");
   });
 
   it("renames a selected thread by id argument", async () => {
@@ -477,7 +477,7 @@ describe("slash commands", () => {
     await executeSlashCommand("rename", "Draft New name", ctx);
 
     expect(ctx.threadActions.renameThread).not.toHaveBeenCalled();
-    expect(ctx.addSystemMessage).toHaveBeenCalledWith("Multiple matching threads: Draft, Draft notes");
+    expect(ctx.addSystemMessage).toHaveBeenCalledWith("Multiple matching threads: Draft (thread-a), Draft notes (thread-b)");
   });
 
   it("documents archive", () => {

tests/settings/settings-tab.test.ts

@@ -33,10 +33,8 @@ describe("settings tab", () => {
   });
 
   it("uses a placeholder for threads without a useful title", () => {
-    expect(threadArchiveDisplayTitle(panelThread({ name: null, preview: "" }))).toBe("Untitled archived thread");
-    expect(threadArchiveDisplayTitle(panelThread({ name: "019e0182-cb70-7a72-ab48-8bc9d0b0d781", preview: "" }))).toBe(
-      "Untitled archived thread",
-    );
+    expect(threadArchiveDisplayTitle(panelThread({ name: null, preview: "" }))).toBe("Untitled thread");
+    expect(threadArchiveDisplayTitle(panelThread({ name: "019e0182-cb70-7a72-ab48-8bc9d0b0d781", preview: "" }))).toBe("Untitled thread");
     expect(threadArchiveDisplayTitle(panelThread({ name: "019e0182-cb70-7a72-ab48-8bc9d0b0d781", preview: "Preview title" }))).toBe(
       "Preview title",
     );