fix(web,mobile): scheduled tasks from Settings start from the project's default branch

apps/mobile/src/features/settings/ScheduledTaskPickerScreens.tsx

@@ -24,7 +24,11 @@ import {
   useScheduledTaskDestinationLabel,
   useScheduledTaskEditor,
 } from "./scheduled-task-editor";
-import { moveDraftToThread, unbindDraftFromThread } from "./scheduledTaskDraft";
+import {
+  moveDraftToThread,
+  scheduledTaskWorktreeBaseRef,
+  unbindDraftFromThread,
+} from "./scheduledTaskDraft";
 
 function MissingTaskDraft() {
   return (
@@ -145,7 +149,11 @@ export function ScheduledTaskBranchPickerRouteScreen() {
       title="Base branch"
       project={project}
       branches={visibleBranches}
-      selectedBranchName={editor.draft.baseRef}
+      selectedBranchName={
+        editor.draft.baseRef.trim() || debouncedQuery.trim() || branches.data === null
+          ? editor.draft.baseRef
+          : scheduledTaskWorktreeBaseRef("", branches.refs)
+      }
       query={query}
       onQueryChange={setQuery}
       loading={

apps/mobile/src/features/settings/SettingsScheduledTasksRouteScreen.tsx

@@ -63,6 +63,7 @@ import { usePreparedConnection } from "../../state/session";
 import { buildModelOptions } from "../../lib/modelOptions";
 import { useProjects, useEnvironmentServerConfig } from "../../state/entities";
 import { useEnvironmentQuery } from "../../state/query";
+import { usePaginatedBranches } from "../../state/queries";
 import { serverEnvironment } from "../../state/server";
 import { useAtomCommand } from "../../state/use-atom-command";
 import { resolveNewTaskBranchLabel } from "../threads/new-task-context-presentation";
@@ -78,6 +79,7 @@ import {
   parseIntervalMinutes,
   scheduledTaskDefaultModel,
   scheduleFromDraft,
+  scheduledTaskWorktreeBaseRef,
   unbindDraftFromThread,
   type ScheduledTaskDraft as Draft,
 } from "./scheduledTaskDraft";
@@ -667,6 +669,21 @@ function TaskForm({
           project.id === draft.task?.projectId),
     )
     .sort((left, right) => Number(right.pinnedAt != null) - Number(left.pinnedAt != null));
+  const automaticBaseRef = draft.workspace === "worktree" && !draft.baseRef.trim();
+  const automaticBaseRefCwd = automaticBaseRef
+    ? (projects.find((project) => project.id === draft.projectId)?.workspaceRoot ?? null)
+    : null;
+  const automaticBaseRefs = usePaginatedBranches({
+    environmentId,
+    cwd: automaticBaseRefCwd,
+    query: "",
+  });
+  const worktreeBaseRef = scheduledTaskWorktreeBaseRef(draft.baseRef, automaticBaseRefs.refs);
+  // Until the project's refs load, the automatic base would save as `main`. A failed lookup falls back to it.
+  const automaticBaseRefLoading =
+    automaticBaseRefCwd !== null &&
+    automaticBaseRefs.data === null &&
+    automaticBaseRefs.error === null;
   const config = useEnvironmentServerConfig(environmentId);
   const destinationLabel = useScheduledTaskDestinationLabel(environmentId, draft.threadId);
   const modelOptions = buildModelOptions(config, null, undefined, draft.projectId);
@@ -708,7 +725,8 @@ function TaskForm({
       saving ||
       dictationPending ||
       taskMissing ||
-      environmentUnavailable
+      environmentUnavailable ||
+      automaticBaseRefLoading
     )
       return;
     // Preserve signatures edited on other clients by sending the task's current value.
@@ -782,7 +800,7 @@ function TaskForm({
             ? { type: "existing_worktree", worktreePath: draft.checkoutPath.trim() }
             : {
                 type: "worktree",
-                baseRef: draft.baseRef.trim() || "main",
+                baseRef: worktreeBaseRef,
                 startFromOrigin: draft.startFromOrigin,
               },
       // Tasks have no mode picker; a mode above the administrator's ceiling is refused.
@@ -995,7 +1013,7 @@ function TaskForm({
             <PickerRow
               label="Base branch"
               value={resolveNewTaskBranchLabel({
-                branchName: draft.baseRef,
+                branchName: automaticBaseRefLoading ? null : worktreeBaseRef,
                 startFromOrigin: draft.startFromOrigin,
                 workspaceMode: "worktree",
               })}
@@ -1309,6 +1327,7 @@ function TaskForm({
           dictationPending ||
           taskMissing ||
           environmentUnavailable ||
+          automaticBaseRefLoading ||
           // The server refuses an enabled webhook task under this policy.
           (draft.enabled && draft.schedule.mode === "webhook" && webhookDenial !== undefined)
         }

apps/mobile/src/features/settings/scheduledTaskDraft.test.ts

@@ -5,9 +5,14 @@ import {
   ProviderDriverKind,
   ProviderInstanceId,
   ProjectId,
+  ScheduledTaskId,
+  type ScheduledTask,
 } from "@t3tools/contracts";
 import {
+  createDraft,
+  editDraft,
   scheduledTaskDefaultModel,
+  scheduledTaskWorktreeBaseRef,
   DEFAULT_SCHEDULE,
   scheduleDraftForTask,
   scheduleFromDraft,
@@ -207,3 +212,62 @@ it("rejects dedupe keys without valid request placeholders", () => {
     scheduleFromDraft({ ...DEFAULT_SCHEDULE, mode: "webhook", coalesceKey: "{{body.bad" }),
   ).toBeNull();
 });
+
+describe("scheduled task worktree base", () => {
+  const ref = (name: string, isDefault = false, isRemote = false) => ({
+    name,
+    isDefault,
+    isRemote,
+  });
+  const rootTask = {
+    id: ScheduledTaskId.make("task"),
+    title: "Review issues",
+    prompt: "Review open issues",
+    enabled: true,
+    schedule: { type: "interval", everyMs: 60_000 },
+    projectId: ProjectId.make("project"),
+    threadId: null,
+    workspaceStrategy: { type: "root" },
+    modelSelection: { instanceId: ProviderInstanceId.make("codex"), model: "gpt-5.4" },
+    runtimeMode: "full-access",
+    interactionMode: "default",
+    createdBy: "user",
+    creationSource: "mobile",
+    createdAt: "2026-09-17T00:00:00.000Z",
+    updatedAt: "2026-09-17T00:00:00.000Z",
+    nextRunAt: null,
+    lastRunAt: null,
+    lastRunStatus: "never",
+    lastRunError: null,
+    runCount: 0,
+  } satisfies ScheduledTask;
+
+  it("leaves the base automatic for new tasks and tasks without a worktree", () => {
+    expect(createDraft(ProjectId.make("project"), null).baseRef).toBe("");
+    expect(editDraft(rootTask).baseRef).toBe("");
+    expect(
+      editDraft({ ...rootTask, workspaceStrategy: { type: "worktree", baseRef: "release" } })
+        .baseRef,
+    ).toBe("release");
+  });
+
+  it("starts an automatic base from the project's default branch", () => {
+    expect(scheduledTaskWorktreeBaseRef("", [ref("feature"), ref("master", true)])).toBe("master");
+    expect(scheduledTaskWorktreeBaseRef(" ", [ref("origin/develop", true, true)])).toBe(
+      "origin/develop",
+    );
+  });
+
+  it("falls back to main or master when the remote records no default", () => {
+    expect(scheduledTaskWorktreeBaseRef("", [ref("feature"), ref("master")])).toBe("master");
+    expect(scheduledTaskWorktreeBaseRef("", [ref("origin/master", false, true)])).toBe(
+      "origin/master",
+    );
+    expect(scheduledTaskWorktreeBaseRef("", [ref("master"), ref("main")])).toBe("main");
+    expect(scheduledTaskWorktreeBaseRef("", [])).toBe("main");
+  });
+
+  it("keeps a base the user picked", () => {
+    expect(scheduledTaskWorktreeBaseRef(" release ", [ref("master", true)])).toBe("release");
+  });
+});

apps/mobile/src/features/settings/scheduledTaskDraft.ts

@@ -8,6 +8,7 @@ import type {
   ScheduledTaskThreadMode,
   ScheduledTaskUpsertSchedule,
   ScheduledTaskWebhookSignature,
+  VcsRef,
   ThreadId,
 } from "@t3tools/contracts";
 
@@ -254,6 +255,22 @@ export function hasScheduledTaskDraftChanges(
   return draftSignature(initial) !== draftSignature(current);
 }
 
+/** An empty base is automatic: the project's default branch, else `main` or `master`. */
+export function scheduledTaskWorktreeBaseRef(
+  baseRef: string,
+  refs: ReadonlyArray<Pick<VcsRef, "name" | "isDefault">>,
+): string {
+  const picked = baseRef.trim();
+  if (picked) return picked;
+  const defaultRef = refs.find((ref) => ref.isDefault);
+  if (defaultRef) return defaultRef.name;
+  for (const name of ["main", "master"]) {
+    const match = refs.find((ref) => ref.name === name || ref.name === `origin/${name}`);
+    if (match) return match.name;
+  }
+  return "main";
+}
+
 export function moveDraftToThread(
   draft: ScheduledTaskDraft,
   thread: { readonly id: ThreadId; readonly projectId: ProjectId },
@@ -301,7 +318,7 @@ export function createDraft(
     schedule: DEFAULT_SCHEDULE,
     threadMode: "new_thread",
     workspace: "worktree",
-    baseRef: "main",
+    baseRef: "",
     checkoutPath: "",
     enabled: true,
     startFromOrigin: true,
@@ -321,7 +338,7 @@ export function editDraft(task: ScheduledTask): ScheduledTaskDraft {
     schedule: scheduleDraftForTask(task),
     threadMode: scheduledTaskThreadMode(task),
     workspace: task.workspaceStrategy.type,
-    baseRef: task.workspaceStrategy.type === "worktree" ? task.workspaceStrategy.baseRef : "main",
+    baseRef: task.workspaceStrategy.type === "worktree" ? task.workspaceStrategy.baseRef : "",
     checkoutPath:
       task.workspaceStrategy.type === "existing_worktree"
         ? task.workspaceStrategy.worktreePath

apps/web/src/components/settings/ScheduledTasksSettings.tsx

@@ -74,6 +74,7 @@ import { scopeThreadRef } from "@t3tools/client-runtime/environment";
 import { environmentAtomList, environmentIdsKey } from "../../state/environmentAtomList";
 import { useThreadSearch } from "../../state/queries";
 import { formatEnvironmentQueryError, useEnvironmentQuery } from "../../state/query";
+import { usePaginatedBranches } from "../../state/queries";
 import { EMPTY_SERVER_PROVIDERS, serverEnvironment } from "../../state/server";
 import { threadFamilies } from "../../state/threads";
 import { useAtomCommand } from "../../state/use-atom-command";
@@ -106,6 +107,7 @@ import {
   scheduleFromDraft,
   scheduleLabel,
   scheduledTaskDefaultModel,
+  scheduledTaskWorktreeBaseRef,
   WEEKDAY_LABELS,
   taskToDraft,
   unbindDraftFromThread,
@@ -179,7 +181,7 @@ const EMPTY_DRAFT: DraftState = {
   threadId: "",
   threadMode: "new_thread",
   workspaceMode: "worktree",
-  baseRef: "main",
+  baseRef: "",
   startFromOrigin: true,
   existingWorktreePath: "",
   modelKey: "",
@@ -1404,6 +1406,19 @@ function ScheduledTaskEditorForm({
     : task;
   const selectedProjectId = draft.projectId || projects[0]?.id || "";
   const selectedProject = projects.find((project) => project.id === selectedProjectId);
+  const automaticBaseRef = draft.workspaceMode === "worktree" && !draft.baseRef.trim();
+  const automaticBaseRefs = usePaginatedBranches({
+    environmentId,
+    cwd: automaticBaseRef ? (selectedProject?.workspaceRoot ?? null) : null,
+    query: "",
+  });
+  const worktreeBaseRef = scheduledTaskWorktreeBaseRef(draft.baseRef, automaticBaseRefs.refs);
+  // Until the project's refs load, the automatic base would save as `main`. A failed lookup falls back to it.
+  const automaticBaseRefLoading =
+    automaticBaseRef &&
+    selectedProject !== undefined &&
+    automaticBaseRefs.data === null &&
+    automaticBaseRefs.error === null;
   const instanceEntries = providerInstanceEntriesFor(
     providers,
     settings,
@@ -1444,7 +1459,8 @@ function ScheduledTaskEditorForm({
       saving ||
       editingTaskMissing ||
       !connected ||
-      tasksQuery.data === null
+      tasksQuery.data === null ||
+      automaticBaseRefLoading
     )
       return;
     const selection = activeSelection;
@@ -1508,7 +1524,7 @@ function ScheduledTaskEditorForm({
           ? { type: "existing_worktree", worktreePath: draft.existingWorktreePath.trim() }
           : {
               type: "worktree",
-              baseRef: draft.baseRef.trim() || "main",
+              baseRef: worktreeBaseRef,
               startFromOrigin: draft.startFromOrigin,
             };
     const input: ScheduledTaskUpsertInput = {
@@ -1573,7 +1589,7 @@ function ScheduledTaskEditorForm({
                   projectId: defaultScheduledTaskProjectId(projectsOn(next.environmentId), scope),
                   modelKey: "",
                   baseModelSelection: null,
-                  baseRef: "main",
+                  baseRef: "",
                   startFromOrigin: true,
                   existingWorktreePath: "",
                 }));
@@ -1724,7 +1740,7 @@ function ScheduledTaskEditorForm({
                 id="scheduled-task-base-ref"
                 environmentId={environmentId}
                 cwd={selectedProject?.workspaceRoot ?? null}
-                value={draft.baseRef}
+                value={automaticBaseRefLoading ? "" : worktreeBaseRef}
                 onValueChange={(baseRef) => setDraft((current) => ({ ...current, baseRef }))}
                 startFromOrigin={draft.startFromOrigin}
                 onStartFromOriginChange={(startFromOrigin) =>
@@ -2133,6 +2149,7 @@ function ScheduledTaskEditorForm({
             editingTaskMissing ||
             !connected ||
             !tasksQuery.data ||
+            automaticBaseRefLoading ||
             (draft.enabled && draft.scheduleMode === "webhook" && webhookDenial !== undefined)
           }
           onClick={() => void submit()}

apps/web/src/components/settings/scheduledTasksSettings.logic.test.ts

@@ -22,6 +22,7 @@ import {
   defaultScheduledTaskProjectId,
   matchesScheduledTaskScope,
   scheduleFromDraft,
+  scheduledTaskWorktreeBaseRef,
   scheduleLabel,
   taskToDraft,
   unbindDraftFromThread,
@@ -171,6 +172,39 @@ describe("editing scheduled task branch settings", () => {
     expect(draft.baseRef).toBe("release");
     expect(draft.startFromOrigin).toBe(false);
   });
+
+  it("leaves the base automatic when a task without a worktree switches to one", () => {
+    const draft = taskToDraft({ ...legacyTask, workspaceStrategy: { type: "root" } });
+    expect(draft.baseRef).toBe("");
+  });
+});
+
+describe("scheduled task worktree base", () => {
+  const ref = (name: string, isDefault = false, isRemote = false) => ({
+    name,
+    isDefault,
+    isRemote,
+  });
+
+  it("starts an automatic base from the project's default branch", () => {
+    expect(scheduledTaskWorktreeBaseRef("", [ref("feature"), ref("master", true)])).toBe("master");
+    expect(scheduledTaskWorktreeBaseRef(" ", [ref("origin/develop", true, true)])).toBe(
+      "origin/develop",
+    );
+  });
+
+  it("falls back to main or master when the remote records no default", () => {
+    expect(scheduledTaskWorktreeBaseRef("", [ref("feature"), ref("master")])).toBe("master");
+    expect(scheduledTaskWorktreeBaseRef("", [ref("origin/master", false, true)])).toBe(
+      "origin/master",
+    );
+    expect(scheduledTaskWorktreeBaseRef("", [ref("master"), ref("main")])).toBe("main");
+    expect(scheduledTaskWorktreeBaseRef("", [])).toBe("main");
+  });
+
+  it("keeps a base the user picked", () => {
+    expect(scheduledTaskWorktreeBaseRef(" release ", [ref("master", true)])).toBe("release");
+  });
 });
 
 describe("fixed-time scheduled tasks", () => {