feat(web): add send shortcut and follow-up controls

apps/web/src/components/ChatView.tsx

@@ -7516,7 +7516,7 @@ export default function ChatView(props: ChatViewProps) {
       !directAnnotation &&
       phase === "running" &&
       activeThreadKey &&
-      settings.followUpBehavior === "queue"
+      (settings.followUpBehavior === "queue") !== (submissionIntent === "alternate")
     ) {
       if (composerRef.current?.validateProviderInput(promptForSend) === false) {
         return;

apps/web/src/components/chat/ChatComposer.tsx

@@ -3955,6 +3955,9 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
             shiftKey: event.shiftKey,
             modifierKey: event.metaKey || event.ctrlKey,
             isDraftThread: routeKind === "draft",
+            isRunning: phase === "running",
+            sendShortcut: settings.sendShortcut,
+            prompt: promptRef.current,
           })
         : null;
     if (submissionIntent) {

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

@@ -1,6 +1,6 @@
 import { Spinner } from "~/components/ui/spinner";
 import { NotificationSettings } from "./NotificationSettings";
-import { ArchiveIcon, ArchiveX, ChevronRightIcon, SettingsIcon } from "lucide-react";
+import { ArchiveIcon, ArchiveX, CheckIcon, ChevronRightIcon, SettingsIcon } from "lucide-react";
 import { Link, useNavigate } from "@tanstack/react-router";
 import type { CSSProperties, ReactNode } from "react";
 import { useCallback, useEffect, useMemo, useRef, useState } from "react";
@@ -105,6 +105,7 @@ import {
   AlertDialogTitle,
 } from "../ui/alert-dialog";
 import { Button } from "../ui/button";
+import { Toggle, ToggleGroup } from "../ui/toggle-group";
 import { Collapsible, CollapsiblePanel, CollapsibleTrigger } from "../ui/collapsible";
 import {
   Dialog,
@@ -578,6 +579,7 @@ export function useSettingsRestore(onRestored?: () => void) {
       ...(settings.composerCollapseOnScroll !== DEFAULT_UNIFIED_SETTINGS.composerCollapseOnScroll
         ? ["Collapse composer on scroll"]
         : []),
+      ...(settings.sendShortcut !== DEFAULT_UNIFIED_SETTINGS.sendShortcut ? ["Send shortcut"] : []),
       ...(settings.followUpBehavior !== DEFAULT_UNIFIED_SETTINGS.followUpBehavior
         ? ["Follow-up behavior"]
         : []),
@@ -639,6 +641,7 @@ export function useSettingsRestore(onRestored?: () => void) {
       settings.confirmThreadDelete,
       settings.confirmThreadUnpin,
       settings.composerCollapseOnScroll,
+      settings.sendShortcut,
       settings.followUpBehavior,
       settings.addProjectBaseDirectory,
       settings.defaultThreadEnvMode,
@@ -752,6 +755,7 @@ export function useSettingsRestore(onRestored?: () => void) {
       proactivePanelsEnabled: DEFAULT_UNIFIED_SETTINGS.proactivePanelsEnabled,
       showSkillsInSlashMenu: DEFAULT_UNIFIED_SETTINGS.showSkillsInSlashMenu,
       composerCollapseOnScroll: DEFAULT_UNIFIED_SETTINGS.composerCollapseOnScroll,
+      sendShortcut: DEFAULT_UNIFIED_SETTINGS.sendShortcut,
       followUpBehavior: DEFAULT_UNIFIED_SETTINGS.followUpBehavior,
       contextWindowMeterEnabled: DEFAULT_UNIFIED_SETTINGS.contextWindowMeterEnabled,
       environmentIdentificationMode: DEFAULT_UNIFIED_SETTINGS.environmentIdentificationMode,
@@ -2086,6 +2090,12 @@ function LegacyFeaturesSection() {
 }
 
 export function GeneralSettingsPanel() {
+  const modifierLabel = isMacPlatform(navigator.platform) ? "⌘" : "Ctrl";
+  const sendShortcutOptions = [
+    { value: "enter", label: "Enter" },
+    { value: "mod-enter-multiline", label: `${modifierLabel} + Enter for multiline prompts` },
+    { value: "mod-enter", label: `${modifierLabel} + Enter always` },
+  ] as const;
   const settings = useScopedSettings();
   const updateSettings = useUpdateScopedSettings();
   const navigate = useNavigate();
@@ -2594,9 +2604,61 @@ export function GeneralSettingsPanel() {
           }
         />
 
+        <SettingsRow
+          {...searchableSetting("send-shortcut")}
+          description="Choose when Enter sends a prompt or inserts a new line"
+          resetAction={
+            settings.sendShortcut !== DEFAULT_UNIFIED_SETTINGS.sendShortcut ? (
+              <SettingResetButton
+                label="send shortcut"
+                onClick={() =>
+                  updateSettings({ sendShortcut: DEFAULT_UNIFIED_SETTINGS.sendShortcut })
+                }
+              />
+            ) : null
+          }
+          control={
+            <Select
+              value={settings.sendShortcut}
+              onValueChange={(value) => {
+                const option = sendShortcutOptions.find((option) => option.value === value);
+                if (option) updateSettings({ sendShortcut: option.value });
+              }}
+            >
+              <SelectTrigger
+                size="sm"
+                className="w-auto min-w-0 max-w-full"
+                aria-label="Send shortcut"
+              >
+                <SelectValue>
+                  {
+                    sendShortcutOptions.find((option) => option.value === settings.sendShortcut)
+                      ?.label
+                  }
+                </SelectValue>
+              </SelectTrigger>
+              <SelectPopup align="end" alignItemWithTrigger={false}>
+                {sendShortcutOptions.map((option) => (
+                  <SelectItem key={option.value} value={option.value}>
+                    <span className="flex items-center justify-between gap-4">
+                      {option.label}
+                      {settings.sendShortcut === option.value && <CheckIcon aria-hidden="true" />}
+                    </span>
+                  </SelectItem>
+                ))}
+              </SelectPopup>
+            </Select>
+          }
+        />
+
         <SettingsRow
           {...searchableSetting("follow-up-behavior")}
-          description="Queue follow-ups while the agent runs or steer the current turn."
+          description={
+            "Queue follow-ups while the agent runs or steer the current run. " +
+            (settings.sendShortcut === "mod-enter-multiline"
+              ? `Press ${modifierLabel} + Enter for single-line prompts or ${modifierLabel} + Shift + Enter for multiline prompts to do the opposite for one message.`
+              : `Press ${modifierLabel}${settings.sendShortcut === "mod-enter" ? " + Shift" : ""} + Enter to do the opposite for one message.`)
+          }
           resetAction={
             settings.followUpBehavior !== DEFAULT_UNIFIED_SETTINGS.followUpBehavior ? (
               <SettingResetButton
@@ -2610,28 +2672,23 @@ export function GeneralSettingsPanel() {
             ) : null
           }
           control={
-            <Select
-              value={settings.followUpBehavior}
-              onValueChange={(value) => {
+            <ToggleGroup
+              aria-label="Follow-up behavior"
+              variant="default"
+              value={[settings.followUpBehavior]}
+              onValueChange={(values) => {
+                const value = values[0];
                 if (value === "queue" || value === "steer") {
                   updateSettings({ followUpBehavior: value });
                 }
               }}
             >
-              <SelectTrigger size="sm" className="w-full sm:w-40" aria-label="Follow-up behavior">
-                <SelectValue>
-                  {settings.followUpBehavior === "queue" ? "Queue" : "Steer"}
-                </SelectValue>
-              </SelectTrigger>
-              <SelectPopup align="end" alignItemWithTrigger={false}>
-                <SelectItem hideIndicator value="queue">
-                  Queue
-                </SelectItem>
-                <SelectItem hideIndicator value="steer">
-                  Steer
-                </SelectItem>
-              </SelectPopup>
-            </Select>
+              {(["queue", "steer"] as const).map((value) => (
+                <Toggle key={value} value={value} variant="pill">
+                  {value === "queue" ? "Queue" : "Steer"}
+                </Toggle>
+              ))}
+            </ToggleGroup>
           }
         />
 

apps/web/src/components/settings/settingsSearch.test.ts

@@ -45,6 +45,10 @@ const ITEMS: ReadonlyArray<SettingsSearchItem> = [
 ];
 
 describe("searchSettings", () => {
+  it.each(["send shortcut", "multiline", "new line"])("finds Send shortcut for %s", (query) => {
+    expect(searchSettings(query).map((item) => item.id)).toContain("send-shortcut");
+  });
+
   it("matches titles, sections, and remembered setting details", () => {
     expect(searchSettings("word", ITEMS).map((item) => item.id)).toEqual(["word-wrap"]);
     expect(searchSettings("network", ITEMS).map((item) => item.id)).toEqual(["network-access"]);

apps/web/src/components/settings/settingsSearch.ts

@@ -298,6 +298,12 @@ export const SETTINGS_SEARCH_ITEMS = [
     to: "/settings/general",
     searchTerms: ["composer rest resting scroll wheel conversation timeline shrink minimize"],
   },
+  {
+    id: "send-shortcut",
+    title: "Send shortcut",
+    to: "/settings/general",
+    searchTerms: ["enter return command ctrl multiline prompt new line composer"],
+  },
   {
     id: "follow-up-behavior",
     title: "Follow-up behavior",

apps/web/src/components/ui/toggle.tsx

@@ -25,6 +25,7 @@ const toggleVariants = cva(
       },
       variant: {
         default: "border-transparent",
+        pill: "border-transparent rounded-full px-3 font-normal text-muted-foreground data-pressed:text-foreground",
         ghost:
           "border-transparent text-foreground shadow-none [:disabled,:active,[data-pressed]]:shadow-none before:shadow-none data-pressed:bg-accent data-pressed:text-accent-foreground disabled:opacity-100 disabled:text-muted-foreground disabled:[&_svg]:opacity-100",
         outline:

apps/web/src/composer-logic.test.ts

@@ -61,6 +61,51 @@ describe("formatAssistantCitationForComposer", () => {
 });
 
 describe("composerSubmissionIntentForEnter", () => {
+  it.each([
+    ["enter", "one line", false, "foreground"],
+    ["enter", "two\nlines", false, "foreground"],
+    ["mod-enter-multiline", "one line", false, "foreground"],
+    ["mod-enter-multiline", "two\nlines", false, null],
+    ["mod-enter-multiline", "two\nlines", true, "foreground"],
+    ["mod-enter", "one line", false, null],
+    ["mod-enter", "one line", true, "foreground"],
+  ] as const)("uses %s for %j with modifier=%s", (sendShortcut, prompt, modifierKey, expected) => {
+    expect(
+      composerSubmissionIntentForEnter({
+        isMobileViewport: false,
+        shiftKey: false,
+        modifierKey,
+        isDraftThread: false,
+        sendShortcut,
+        prompt,
+      }),
+    ).toBe(expected);
+  });
+
+  it.each([
+    ["enter", false, "alternate"],
+    ["enter", true, null],
+    ["mod-enter-multiline", false, "foreground"],
+    ["mod-enter-multiline", true, "alternate"],
+    ["mod-enter", false, "foreground"],
+    ["mod-enter", true, "alternate"],
+  ] as const)(
+    "resolves running follow-ups with %s and shift=%s",
+    (sendShortcut, shiftKey, expected) => {
+      expect(
+        composerSubmissionIntentForEnter({
+          isMobileViewport: false,
+          shiftKey,
+          modifierKey: true,
+          isDraftThread: false,
+          isRunning: true,
+          sendShortcut,
+          prompt: "two\nlines",
+        }),
+      ).toBe(expected);
+    },
+  );
+
   it("submits plain Enter on desktop", () => {
     expect(
       composerSubmissionIntentForEnter({

apps/web/src/composer-logic.ts

@@ -1,3 +1,4 @@
+import type { ClientSettings } from "@t3tools/contracts/settings";
 import type { AssistantCitation } from "@t3tools/contracts";
 import {
   serializeAssistantCitation,
@@ -10,7 +11,7 @@ import {
 
 export type ComposerTriggerKind = "path" | "pull-request" | "slash-command" | "skill";
 export type ComposerSlashCommand = "model" | "plan" | "default";
-export type ComposerSubmissionIntent = "foreground" | "background";
+export type ComposerSubmissionIntent = "foreground" | "background" | "alternate";
 
 export interface ComposerTrigger {
   kind: ComposerTriggerKind;
@@ -28,9 +29,17 @@ export function composerSubmissionIntentForEnter(input: {
   shiftKey: boolean;
   modifierKey: boolean;
   isDraftThread: boolean;
+  isRunning?: boolean;
+  sendShortcut?: ClientSettings["sendShortcut"];
+  prompt?: string;
 }): ComposerSubmissionIntent | null {
-  if (input.isMobileViewport || input.shiftKey) {
-    return null;
+  const requiresModifier =
+    input.sendShortcut === "mod-enter" ||
+    (input.sendShortcut === "mod-enter-multiline" && /[\r\n]/.test(input.prompt ?? ""));
+  if (input.isMobileViewport || (requiresModifier && !input.modifierKey)) return null;
+  if (input.shiftKey && !(requiresModifier && input.modifierKey && input.isRunning)) return null;
+  if (input.isRunning && input.modifierKey && (!requiresModifier || input.shiftKey)) {
+    return "alternate";
   }
   return input.modifierKey && input.isDraftThread ? "background" : "foreground";
 }

docs/user/keybindings.md

@@ -5,6 +5,15 @@ also lists the command IDs and defaults available in your version.
 
 ## Composer controls
 
+In **Settings → General → Send shortcut**, choose whether Enter sends, requires
+`mod+Enter` for multiline prompts, or always requires `mod+Enter`. `Shift+Enter`
+inserts a new line. This applies to the web and desktop composer at desktop widths.
+
+**Follow-up behavior** chooses Queue or Steer while the agent runs. Use
+`mod+Enter` to do the opposite for one message. When sending requires `mod+Enter`,
+use `mod+Shift+Enter` for the opposite action. In a new thread, `mod+Enter` keeps
+starting the thread in the background.
+
 Use `mod+shift+m` to choose a model and `mod+shift+h` to choose a host.
 Use `mod+shift+e` for effort, `mod+shift+a` for access mode, `mod+shift+x` for the
 workspace, and `mod+shift+g` for the Git branch. The workspace menu includes the

packages/contracts/src/settings.test.ts

@@ -529,6 +529,17 @@ describe("ClientSettings context window meter", () => {
   });
 });
 
+describe("ClientSettings send shortcut", () => {
+  it("defaults to Enter and validates the supported choices", () => {
+    expect(decodeClientSettings({}).sendShortcut).toBe("enter");
+    for (const sendShortcut of ["enter", "mod-enter-multiline", "mod-enter"]) {
+      expect(decodeClientSettings({ sendShortcut }).sendShortcut).toBe(sendShortcut);
+      expect(decodeClientSettingsPatch({ sendShortcut }).sendShortcut).toBe(sendShortcut);
+    }
+    expect(() => decodeClientSettingsPatch({ sendShortcut: "invalid" })).toThrow();
+  });
+});
+
 describe("ClientSettings follow-up behavior", () => {
   it("defaults to queue and accepts either behavior", () => {
     expect(decodeClientSettings({}).followUpBehavior).toBe("queue");

packages/contracts/src/settings.ts

@@ -430,6 +430,9 @@ export const ClientSettingsSchema = Schema.Struct({
   // Desktop resting composer: scrolling an existing thread's conversation
   // settles the composer into its single-line layout. Losing focus never does.
   composerCollapseOnScroll: Schema.Boolean.pipe(Schema.withDecodingDefault(Effect.succeed(true))),
+  sendShortcut: Schema.Literals(["enter", "mod-enter-multiline", "mod-enter"]).pipe(
+    Schema.withDecodingDefault(Effect.succeed("enter")),
+  ),
   followUpBehavior: Schema.Literals(["queue", "steer"]).pipe(
     Schema.withDecodingDefault(Effect.succeed("queue")),
   ),
@@ -1502,6 +1505,7 @@ export const ClientSettingsPatch = Schema.Struct({
   planModeEnabled: Schema.optionalKey(Schema.Boolean),
   contextWindowMeterEnabled: Schema.optionalKey(Schema.Boolean),
   composerCollapseOnScroll: Schema.optionalKey(Schema.Boolean),
+  sendShortcut: Schema.optionalKey(Schema.Literals(["enter", "mod-enter-multiline", "mod-enter"])),
   followUpBehavior: Schema.optionalKey(Schema.Literals(["queue", "steer"])),
   proactivePanelsEnabled: Schema.optionalKey(Schema.Boolean),
   showSkillsInSlashMenu: Schema.optionalKey(Schema.Boolean),