fix(chat): preserve delivered plain text verbatim

app/(authenticated)/chat/[sessionId]/_components/conversation/index.test.tsx

@@ -4,8 +4,57 @@ import { renderToStaticMarkup } from "react-dom/server";
 import { describe, expect, it } from "vitest";
 import { ChatConversation } from ".";
 import type { ChatAgent } from "../chat-agent";
+import { sendMessageOutputSchema } from "@shared/chat/message-delivery";
 
 describe("chat conversation", () => {
+  it.each([
+    "Please keep *literal stars* in the filename.",
+    "Save the `draft` filename.",
+    "#42 is my order number.",
+    "1. First note\n2. Second note",
+    "Line one  \nLine two",
+  ])("renders delivered plain text exactly: %s", async (text) => {
+    const agent = await deliveredAgent(text);
+    const markup = renderToStaticMarkup(
+      <ChatConversation agent={agent} traceView="imessage" />
+    );
+    expect(markup).toContain(text);
+    expect(markup).not.toMatch(/<(?:em|code|ol|h1)[ >]/u);
+  });
+
+  it.each([
+    "https://example.com/report",
+    "See https://example.com/report_2026?view=notes for details.",
+  ])("keeps delivered HTTP URLs tappable: %s", async (text) => {
+    const markup = renderToStaticMarkup(
+      <ChatConversation
+        agent={await deliveredAgent(text)}
+        traceView="imessage"
+      />
+    );
+    expect(markup).toContain('data-streamdown="link"');
+    expect(markup).toContain("https://example.com/report");
+    expect(markup).toContain(
+      text.startsWith("See ") ? "for details." : "https://example.com/report"
+    );
+  });
+
+  it("keeps intentional trace Markdown", () => {
+    const agent = {
+      data: { messages: [message("turn-1:user", "*trace emphasis*")] },
+      error: undefined,
+      events: [],
+      respond: async () => undefined,
+      status: "ready",
+    } satisfies Pick<
+      ChatAgent,
+      "data" | "error" | "events" | "respond" | "status"
+    >;
+    expect(
+      renderToStaticMarkup(<ChatConversation agent={agent} traceView="trace" />)
+    ).toContain("<em>trace emphasis</em>");
+  });
+
   it("shows send_message output instead of assistant stream text", () => {
     const agent = {
       data: {
@@ -109,6 +158,41 @@ describe("chat conversation", () => {
   });
 });
 
+async function deliveredAgent(text: string) {
+  const output = sendMessageOutputSchema.parse({ kind: "message", text });
+  return {
+    data: {
+      messages: [
+        { id: "turn-1:assistant", parts: [], role: "assistant" as const },
+      ],
+    },
+    error: undefined,
+    events: [
+      {
+        data: {
+          result: {
+            callId: "call-plain",
+            kind: "tool-result" as const,
+            output,
+            toolName: "send_message",
+          },
+          sequence: 0,
+          status: "completed" as const,
+          stepIndex: 0,
+          turnId: "turn-1",
+        },
+        meta: { at: "2026-10-07T00:00:00.000Z", id: "event-plain" },
+        type: "action.result" as const,
+      },
+    ],
+    respond: async () => undefined,
+    status: "ready" as const,
+  } satisfies Pick<
+    ChatAgent,
+    "data" | "error" | "events" | "respond" | "status"
+  >;
+}
+
 function message(id: string, text: string): EveMessage {
   return {
     id,

app/(authenticated)/chat/[sessionId]/_components/conversation/message/parts.tsx

@@ -34,6 +34,24 @@ export function AgentMessagePart({
     case "step-start":
       return null;
     case "text":
+      if (userVisibleOnly) {
+        return (
+          <div className="wrap-break-word whitespace-pre-wrap">
+            {part.text.split(/(https?:\/\/\S+)/iu).map((text, index) =>
+              /^https?:\/\//iu.test(text) ? (
+                <MessageResponse
+                  className="inline [&>p]:inline"
+                  key={`${String(index)}:${text}`}
+                >
+                  {text}
+                </MessageResponse>
+              ) : (
+                text
+              )
+            )}
+          </div>
+        );
+      }
       return (
         <MessageResponse caret="block" isAnimating={showCaret}>
           {part.text}

app/(authenticated)/chat/[sessionId]/_lib/message-events.test.ts

@@ -153,7 +153,7 @@ describe("iMessage event projection", () => {
 
     expect(sentMessages(events).get("turn-1:assistant")).toEqual([
       expect.objectContaining({
-        parts: [expect.objectContaining({ text: "line one  \nline two" })],
+        parts: [expect.objectContaining({ text: "line one\nline two" })],
       }),
     ]);
   });

app/(authenticated)/chat/[sessionId]/_lib/message-events.ts

@@ -61,12 +61,7 @@ export function sentMessages(events: readonly MessageStreamEvent[]) {
       });
     } else if (delivery) {
       const { output } = delivery;
-      // Delivered text is plain and reaches the user verbatim. The chat view
-      // renders text parts as Markdown, so keep every line break as a hard break.
-      const text =
-        output.kind === "link"
-          ? output.url
-          : output.text?.replaceAll("\n", "  \n");
+      const text = output.kind === "link" ? output.url : output.text;
       if (text) {
         parts.push({
           state: "done",

tests/agent/tools/share-contact.test.ts

@@ -72,6 +72,25 @@ beforeEach(() => {
 afterEach(() => vi.unstubAllGlobals());
 
 describe("share_contact", () => {
+  it("preserves exact plain text in the send_message producer", async () => {
+    const text =
+      "Keep *literal stars*, `draft` and the spaces  \nbefore this line.";
+    const resolve = messaging.events["turn.started"];
+    if (!resolve) throw new Error("Expected messaging resolver.");
+    const tools = await resolve({}, {
+      channel: { kind: "http", metadata: {} },
+      messages: [],
+      model: null,
+      session: toolContext().session,
+    } satisfies DynamicResolveContext);
+    if (!tools || !("send_message" in tools))
+      throw new Error("Expected send_message.");
+    const input = sendMessageOutputSchema.parse({ kind: "message", text });
+    expect(await tools.send_message.execute(input, toolContext())).toEqual(
+      input
+    );
+  });
+
   it("renders the contact in browser chat and suppresses repeats without sending to Linq", async () => {
     const tool = await shareContactTool();
     const first = await tool.execute(