feat: collapse large pasted text into expandable blocks

- Keep pasted content intact for provider submissions
- Show compact expandable pasted-text blocks across web and mobile

Author: asfires

apps/mobile/src/features/threads/ThreadFeed.tsx

@@ -4,6 +4,7 @@ import { type LegendListRef } from "@legendapp/list/react-native";
 import type { EnvironmentId, MessageId, ThreadId, TurnId } from "@t3tools/contracts";
 import { CHAT_LIST_ANCHOR_OFFSET, resolveChatListAnchoredEndSpace } from "@t3tools/shared/chatList";
 import { formatElapsed } from "@t3tools/shared/orchestrationTiming";
+import { materializePastedText, splitPastedTextSegments } from "@t3tools/shared/pastedText";
 import { SymbolView } from "../../components/AppSymbol";
 import { HeaderHeightContext } from "@react-navigation/elements";
 import { useNavigation } from "@react-navigation/native";
@@ -924,7 +925,7 @@ function renderFeedEntry(
             {message.text.trim().length > 0 ? (
               <CopyTextButton
                 accessibilityLabel="Copy message"
-                text={message.text}
+                text={materializePastedText(message.text)}
                 tintColor={iconSubtleColor}
                 buttonSize={28}
                 iconSize={13}
@@ -1040,6 +1041,33 @@ function UserMessageContent(props: {
   readonly skills?: ReadonlyArray<SelectableMarkdownSkill>;
   readonly onLinkPress: (href: string) => void;
 }) {
+  const pastedTextSegments = splitPastedTextSegments(props.text);
+  if (pastedTextSegments.some((segment) => segment.type === "pasted-text")) {
+    let pastedTextOrdinal = 0;
+    let segmentOffset = 0;
+    return (
+      <View className="w-full gap-2">
+        {pastedTextSegments.map((segment) => {
+          const currentOffset = segmentOffset;
+          segmentOffset += segment.type === "text" ? segment.text.length : segment.source.length;
+          if (segment.type === "pasted-text") {
+            pastedTextOrdinal += 1;
+            return (
+              <MobilePastedTextBlock
+                key={`pasted-text:${currentOffset}`}
+                text={segment.text}
+                ordinal={pastedTextOrdinal}
+              />
+            );
+          }
+          return segment.text.trim().length > 0 ? (
+            <UserMessageContent key={`text:${currentOffset}`} {...props} text={segment.text} />
+          ) : null;
+        })}
+      </View>
+    );
+  }
+
   const segments = parseReviewCommentMessageSegments(props.text);
   const hasReviewComment = segments.some((segment) => segment.kind === "review-comment");
   if (!hasReviewComment) {
@@ -1109,6 +1137,41 @@ function UserMessageContent(props: {
   );
 }
 
+const MobilePastedTextBlock = memo(function MobilePastedTextBlock(props: {
+  readonly text: string;
+  readonly ordinal: number;
+}) {
+  const [expanded, setExpanded] = useState(false);
+  const iconColor = useThemeColor("--color-icon-muted");
+
+  return (
+    <View className="max-w-full items-start gap-1">
+      <Pressable
+        accessibilityRole="button"
+        accessibilityState={{ expanded }}
+        accessibilityLabel={`${expanded ? "Hide" : "Show"} pasted text ${props.ordinal}`}
+        className="flex-row items-center gap-1.5 rounded-lg border border-border bg-foreground/5 px-2 py-1"
+        onPress={() => setExpanded((value) => !value)}
+      >
+        <Text className="font-t3-medium text-xs text-foreground">Pasted text #{props.ordinal}</Text>
+        <SymbolView
+          name={expanded ? "chevron.down" : "chevron.right"}
+          size={12}
+          tintColor={iconColor}
+          type="monochrome"
+        />
+      </Pressable>
+      {expanded ? (
+        <ScrollView className="max-h-72 max-w-full rounded-xl border border-border bg-background/50 p-2.5">
+          <Text selectable className="font-mono text-xs leading-5 text-foreground">
+            {props.text}
+          </Text>
+        </ScrollView>
+      ) : null}
+    </View>
+  );
+});
+
 const ReviewCommentCard = memo(function ReviewCommentCard(props: {
   readonly comment: ReviewInlineComment;
   readonly colors: ReviewCommentColors;

apps/server/src/orchestration/Layers/ProviderCommandReactor.test.ts

@@ -12,6 +12,7 @@ import {
   type VcsRef,
 } from "@t3tools/contracts";
 import { createModelSelection } from "@t3tools/shared/model";
+import { serializePastedText } from "@t3tools/shared/pastedText";
 import {
   ApprovalRequestId,
   CheckpointRef,
@@ -713,6 +714,7 @@ describe("ProviderCommandReactor", () => {
   it("reacts to thread.turn.start by ensuring session and sending provider turn", async () => {
     const harness = await createHarness();
     const now = "2026-01-01T00:00:00.000Z";
+    const storedMessageText = `hello ${serializePastedText("exact pasted body")} reactor`;
 
     await Effect.runPromise(
       harness.engine.dispatch({
@@ -722,7 +724,7 @@ describe("ProviderCommandReactor", () => {
         message: {
           messageId: asMessageId("user-message-1"),
           role: "user",
-          text: "hello reactor",
+          text: storedMessageText,
           attachments: [],
         },
         interactionMode: DEFAULT_PROVIDER_INTERACTION_MODE,
@@ -742,12 +744,16 @@ describe("ProviderCommandReactor", () => {
       },
       runtimeMode: "approval-required",
     });
+    expect(harness.sendTurn.mock.calls[0]?.[0]).toMatchObject({
+      input: "hello exact pasted body reactor",
+    });
 
     const readModel = await harness.readModel();
     const thread = readModel.threads.find((entry) => entry.id === ThreadId.make("thread-1"));
     expect(thread?.session?.threadId).toBe("thread-1");
     expect(thread?.session?.status).toBe("starting");
     expect(thread?.session?.runtimeMode).toBe("approval-required");
+    expect(thread?.messages[0]?.text).toBe(storedMessageText);
   });
 
   it("recreates a pruned managed worktree before resuming a provider turn", async () => {

apps/server/src/orchestration/Layers/ProviderCommandReactor.ts

@@ -34,6 +34,7 @@ import * as Option from "effect/Option";
 import * as Schema from "effect/Schema";
 import * as Stream from "effect/Stream";
 import { makeDrainableWorker } from "@t3tools/shared/DrainableWorker";
+import { materializePastedText } from "@t3tools/shared/pastedText";
 
 import { resolveThreadWorkspaceCwd } from "../../checkpointing/Utils.ts";
 import { increment, orchestrationEventsProcessedTotal } from "../../observability/Metrics.ts";
@@ -171,7 +172,9 @@ function formatThreadTitleSection(message: ThreadTitleMessage): string | undefin
   if (message.role === "system") {
     return undefined;
   }
-  const text = message.text.trim();
+  const text = (
+    message.role === "user" ? materializePastedText(message.text) : message.text
+  ).trim();
   const attachmentSummary = (message.attachments ?? [])
     .map((attachment) => attachment.name)
     .join(", ");
@@ -1213,6 +1216,7 @@ const make = Effect.gen(function* () {
       });
       return;
     }
+    const messageText = materializePastedText(message.text);
 
     // First gate: when retract won before provider startup, persist the
     // send-cancelled handoff and do not create a provider session. WO3 owns
@@ -1236,7 +1240,7 @@ const make = Effect.gen(function* () {
           projects: project ? [project] : [],
         }) ?? process.cwd();
       const generationInput = {
-        messageText: message.text,
+        messageText,
         ...(message.attachments !== undefined ? { attachments: message.attachments } : {}),
         ...(event.payload.titleSeed !== undefined ? { titleSeed: event.payload.titleSeed } : {}),
       };
@@ -1296,7 +1300,7 @@ const make = Effect.gen(function* () {
 
     const sendTurnRequest = yield* buildSendTurnRequestForThread({
       threadId: event.payload.threadId,
-      messageText: message.text,
+      messageText,
       ...(message.attachments !== undefined ? { attachments: message.attachments } : {}),
       ...(event.payload.modelSelection !== undefined
         ? { modelSelection: event.payload.modelSelection }

apps/web/src/components/ChatView.logic.ts

@@ -21,6 +21,7 @@ import {
   type TerminalContextDraft,
 } from "../lib/terminalContext";
 import type { DraftThreadEnvMode } from "../composerDraftStore";
+import { materializePastedText } from "@t3tools/shared/pastedText";
 
 export const LAST_INVOKED_SCRIPT_BY_PROJECT_KEY = "t3code:last-invoked-script-by-project";
 export const MAX_HIDDEN_MOUNTED_TERMINAL_THREADS = 10;
@@ -289,7 +290,9 @@ export function deriveComposerSendState(options: {
   expiredTerminalContextCount: number;
   hasSendableContent: boolean;
 } {
-  const trimmedPrompt = stripInlineTerminalContextPlaceholders(options.prompt).trim();
+  const trimmedPrompt = stripInlineTerminalContextPlaceholders(
+    materializePastedText(options.prompt),
+  ).trim();
   const sendableTerminalContexts = filterTerminalContextsWithText(options.terminalContexts);
   const expiredTerminalContextCount =
     options.terminalContexts.length - sendableTerminalContexts.length;

apps/web/src/components/ChatView.tsx

@@ -50,6 +50,7 @@ import { CHAT_LIST_ANCHOR_OFFSET } from "@t3tools/shared/chatList";
 import { projectScriptCwd, projectScriptRuntimeEnv } from "@t3tools/shared/projectScripts";
 import { truncate } from "@t3tools/shared/String";
 import { nextTerminalId, resolveTerminalSessionLabel } from "@t3tools/shared/terminalLabels";
+import { materializePastedText } from "@t3tools/shared/pastedText";
 import { Debouncer } from "@tanstack/react-pacer";
 import { useAtomValue } from "@effect/atom-react";
 import {
@@ -214,6 +215,7 @@ import {
 import {
   appendTerminalContextsToPrompt,
   formatTerminalContextLabel,
+  stripInlineTerminalContextPlaceholders,
   type TerminalContextDraft,
   type TerminalContextSelection,
 } from "../lib/terminalContext";
@@ -5201,7 +5203,7 @@ function ChatViewContent(props: ChatViewProps) {
     });
     if (!directAnnotation && showPlanFollowUpPrompt && activeProposedPlan) {
       const followUp = resolvePlanFollowUpSubmission({
-        draftText: trimmed,
+        draftText: trimmed.length > 0 ? stripInlineTerminalContextPlaceholders(promptForSend) : "",
         planMarkdown: activeProposedPlan.planMarkdown,
       });
       const outgoingFollowUpText = formatOutgoingPrompt({
@@ -5211,7 +5213,10 @@ function ChatViewContent(props: ChatViewProps) {
         effort: ctxSelectedPromptEffort,
         text: followUp.text.trim(),
       });
-      if (composerRef.current?.validateProviderInput(outgoingFollowUpText) === false) {
+      if (
+        composerRef.current?.validateProviderInput(materializePastedText(outgoingFollowUpText)) ===
+        false
+      ) {
         return;
       }
       promptRef.current = "";
@@ -5307,7 +5312,10 @@ function ChatViewContent(props: ChatViewProps) {
       effort: ctxSelectedPromptEffort,
       text: messageTextForSend || IMAGE_ONLY_MESSAGE_PLACEHOLDER,
     });
-    if (composerRef.current?.validateProviderInput(outgoingMessageText) === false) {
+    if (
+      composerRef.current?.validateProviderInput(materializePastedText(outgoingMessageText)) ===
+      false
+    ) {
       return;
     }
 

apps/web/src/components/ComposerPromptEditor.test.ts

@@ -59,6 +59,7 @@ describe("registerComposerInlineTokenPaste", () => {
     );
     registerComposerInlineTokenPaste(editor, {
       createMentionNode: (path) => $createTextNode(`<mention:${path}>`),
+      createPastedTextNode: (text) => $createTextNode(`<paste:${text}>`),
       getExpandedAbsoluteOffsetForPoint: () => 0,
     });
     editor.registerCommand(PASTE_COMMAND, plainTextFallback, COMMAND_PRIORITY_EDITOR);
@@ -104,6 +105,7 @@ describe("registerComposerInlineTokenPaste", () => {
     );
     registerComposerInlineTokenPaste(editor, {
       createMentionNode: (path) => $createTextNode(`<mention:${path}>`),
+      createPastedTextNode: (text) => $createTextNode(`<paste:${text}>`),
       getExpandedAbsoluteOffsetForPoint: () => 0,
     });
     editor.registerCommand(PASTE_COMMAND, plainTextFallback, COMMAND_PRIORITY_EDITOR);
@@ -138,6 +140,7 @@ describe("registerComposerInlineTokenPaste", () => {
     );
     registerComposerInlineTokenPaste(editor, {
       createMentionNode: (path) => $createTextNode(`<mention:${path}>`),
+      createPastedTextNode: (text) => $createTextNode(`<paste:${text}>`),
       getExpandedAbsoluteOffsetForPoint: () => 0,
     });
     editor.registerCommand(PASTE_COMMAND, plainTextFallback, COMMAND_PRIORITY_EDITOR);
@@ -158,4 +161,37 @@ describe("registerComposerInlineTokenPaste", () => {
       "<mention:@scope/pkg/sub> ",
     );
   });
+
+  it("turns a large plain-text paste into one atomic presentation node", () => {
+    vi.stubGlobal("ClipboardEvent", TestClipboardEvent);
+    const editor = createEditor();
+    const pastedText = "line of pasted text\n".repeat(20);
+    const plainTextFallback = vi.fn(() => true);
+
+    editor.update(
+      () => {
+        const paragraph = $createParagraphNode();
+        $getRoot().append(paragraph);
+        paragraph.selectEnd();
+      },
+      { discrete: true },
+    );
+    registerComposerInlineTokenPaste(editor, {
+      createMentionNode: (path) => $createTextNode(`<mention:${path}>`),
+      createPastedTextNode: (text) => $createTextNode(`<paste:${text}>`),
+      getExpandedAbsoluteOffsetForPoint: () => 0,
+    });
+    editor.registerCommand(PASTE_COMMAND, plainTextFallback, COMMAND_PRIORITY_EDITOR);
+
+    const event = new TestClipboardEvent(pastedText);
+    editor.update(() => editor.dispatchCommand(PASTE_COMMAND, event as ClipboardEvent), {
+      discrete: true,
+    });
+
+    expect(plainTextFallback).not.toHaveBeenCalled();
+    expect(event.defaultPrevented).toBe(true);
+    expect(editor.getEditorState().read(() => $getRoot().getTextContent())).toBe(
+      `<paste:${pastedText}>`,
+    );
+  });
 });