fix: print the running tool once, not twice (#17)

src/__tests__/markdown.test.ts

@@ -116,6 +116,64 @@ describe("buildThreadMarkdown", () => {
     expect(markdown).not.toContain("Thinking");
   });
 
+  it("says what a running tool is doing exactly once, before any text arrives", () => {
+    // The reported bug, from a screenshot: the activity line and the answer
+    // placeholder both printed "Reading a page", one directly above the other.
+    const markdown = buildThreadMarkdown([
+      message({
+        role: "assistant",
+        isStreaming: true,
+        text: "",
+        activity: { label: "Reading a page", count: 1 },
+      }),
+    ]);
+
+    expect(markdown.match(/Reading a page/g)).toHaveLength(1);
+    // With nothing to read yet, the activity line is the stand-in, so the cursor
+    // rides on it rather than sitting on a line of its own.
+    expect(markdown).toContain(`_Reading a page…_ ${STREAMING_CURSOR}`);
+  });
+
+  it("keeps the activity line once the answer has started arriving", () => {
+    // The other half of the fix: a tool that starts mid-answer has to stay on
+    // screen, which is why the line is not just a stand-in for missing text.
+    const markdown = buildThreadMarkdown([
+      message({
+        role: "assistant",
+        isStreaming: true,
+        text: "Here is what I found.",
+        activity: { label: "Reading a page", count: 1 },
+      }),
+    ]);
+
+    expect(markdown).toContain("_Reading a page…_");
+    expect(markdown).toContain("Here is what I found.");
+    // And the cursor follows the answer, not the activity line.
+    expect(markdown).toContain(`Here is what I found. ${STREAMING_CURSOR}`);
+    expect(markdown).not.toContain(`_Reading a page…_ ${STREAMING_CURSOR}`);
+  });
+
+  it("names a repeat rather than leaving a bare count to be interpreted", () => {
+    const markdown = buildThreadMarkdown([
+      message({
+        role: "assistant",
+        isStreaming: true,
+        activity: { label: "Searching the web", count: 2 },
+      }),
+    ]);
+
+    expect(markdown).toContain("the same call again (2)");
+  });
+
+  it("drops the activity line when the message is no longer streaming", () => {
+    const markdown = buildThreadMarkdown([
+      message({ role: "assistant", text: "done", activity: { label: "Searching the web", count: 1 } }),
+    ]);
+
+    expect(markdown).not.toContain("Searching the web");
+    expect(markdown).not.toContain(STREAMING_CURSOR);
+  });
+
   it("shows a placeholder while an answer has no text yet", () => {
     expect(buildThreadMarkdown([message({ role: "assistant", isStreaming: true })])).toContain("Thinking");
     expect(buildThreadMarkdown([message({ role: "assistant" })])).toContain("No response");

src/__tests__/thread.test.ts

@@ -1,9 +1,11 @@
 import { describe, expect, it } from "vitest";
-import { buildThread, type LiveState } from "../lib/thread";
+import { buildThread, describeActivity, type LiveState } from "../lib/thread";
 import type { ChatTurn } from "../lib/types";
 
 const idle: LiveState = { isStreaming: false, response: "", thinking: "" };
 
+const activity = { label: "Reading a page", count: 1 };
+
 function turn(id: string, prompt: string, response: string, overrides: Partial<ChatTurn> = {}): ChatTurn {
   return {
     id,
@@ -133,3 +135,46 @@ describe("buildThread", () => {
     expect(thread[0].error).toBe("Request failed");
   });
 });
+
+describe("carrying the running tool", () => {
+  const live: LiveState = { isStreaming: true, response: "", thinking: "", activity };
+
+  it("puts it on the message being streamed", () => {
+    const thread = buildThread([turn("t1", "q", "a")], live);
+    const assistant = thread.find((message) => message.role === "assistant");
+
+    expect(assistant?.activity).toEqual(activity);
+  });
+
+  it("keeps it off every earlier message", () => {
+    // Only the newest turn can be mid-flight, and an older answer carrying a
+    // "Searching the web" line would be a claim about a finished turn.
+    const thread = buildThread([turn("t1", "q", "a"), turn("t2", "q2", "a2")], live);
+
+    expect(thread.slice(2).every((message) => message.activity === undefined)).toBe(true);
+  });
+
+  it("drops it once the turn is over", () => {
+    const thread = buildThread([turn("t1", "q", "a")], { ...idle, activity });
+
+    expect(thread.every((message) => message.activity === undefined)).toBe(true);
+  });
+
+  it("never puts one on a question", () => {
+    const thread = buildThread([turn("t1", "q", "a")], live);
+
+    expect(thread.find((message) => message.role === "user")?.activity).toBeUndefined();
+  });
+});
+
+describe("describeActivity", () => {
+  it("is just the label for a first call", () => {
+    expect(describeActivity({ label: "Reading a page", count: 1 })).toBe("Reading a page");
+  });
+
+  it("says a repeat is a repeat, because a bare number reads as progress", () => {
+    expect(describeActivity({ label: "Reading a page", count: 3 })).toBe(
+      "Reading a page · the same call again (3)",
+    );
+  });
+});

src/lib/components/ChatView.tsx

@@ -2,7 +2,7 @@ import { Action, ActionPanel, Icon, LaunchType, List, launchCommand } from "@vic
 import { useCallback, useEffect, useMemo, useState } from "react";
 import { readAttachment } from "../attachments";
 import { runAutoDelete } from "../cleanup";
-import { useChat, type ToolActivity } from "../hooks/useChat";
+import { useChat } from "../hooks/useChat";
 import { usePreferences } from "../hooks/usePreferences";
 import { useVisionSupport } from "../hooks/useVision";
 import { buildThreadMarkdown, renderAttachments, type TranscriptOptions } from "../markdown";
@@ -63,18 +63,6 @@ const DEFAULT_IMAGE_PROMPT = "What is in this image?";
 /** The reminder shown while a snip is attached but not yet sent. */
 const PENDING_NOTE = "_Ask a question about it, or press Return to send it as it is._";
 
-/**
- * The line that shows what Lam is doing right now.
- *
- * A count on its own reads as progress, so the second time round says what it is:
- * the same call, asked again. That is the visible half of the loop guard in
- * `agent.ts`, and it is the only warning the user gets before a turn is cut short.
- */
-function describeActivity(activity: ToolActivity): string {
-  if (activity.count <= 1) return `_${activity.label}…_`;
-  return `_${activity.label} · the same call again (${activity.count})_`;
-}
-
 export interface ChatViewProps {
   /** Opens a specific conversation instead of resuming the latest one. */
   initialSession?: Session;
@@ -138,8 +126,6 @@ function ChatSession({
   const chat = useChat({ preferences, initialSession, vision: vision.support });
   const { replaceSession } = chat;
   const { canSeeImages } = vision;
-  const { activity } = chat;
-
   const [input, setInput] = useState(initialPrompt ?? "");
   const [summaries, setSummaries] = useState<SessionSummary[] | undefined>(undefined);
   // One flag, not two. See the startup effect below for why that matters.
@@ -232,8 +218,16 @@ function ChatSession({
         response: chat.streamingResponse,
         thinking: chat.streamingThinking,
         status: chat.status,
+        activity: chat.activity,
       }),
-    [chat.session.turns, chat.isStreaming, chat.streamingResponse, chat.streamingThinking, chat.status],
+    [
+      chat.session.turns,
+      chat.isStreaming,
+      chat.streamingResponse,
+      chat.streamingThinking,
+      chat.status,
+      chat.activity,
+    ],
   );
 
   const transcriptOptions = useMemo<TranscriptOptions>(
@@ -255,12 +249,10 @@ function ChatSession({
       // The preview comes first so the captured image is visible before the user
       // decides what to ask about it, rather than only after sending.
       pending ? `${renderAttachments([pending])}\n\n${PENDING_NOTE}` : undefined,
-      // Deliberately not gated on the Show Tool Calls preference. That setting is
-      // about the finished transcript, where a list of names adds nothing. This
-      // is about the turn in flight, where the same tool coming round a second
-      // time is the difference between a long answer and a stuck one, and hiding
-      // it would leave the user watching a spinner they cannot interpret.
-      activity ? describeActivity(activity) : undefined,
+      // Deliberately nothing about the running tool here. That line is rendered by
+      // the transcript, on the live message, so that one fact is printed once:
+      // adding it here as well put "Reading a page" on screen twice, one line
+      // above the other, while a tool ran before any text had arrived.
     ].filter((note): note is string => Boolean(note));
 
     // The placeholder is what tells a user that the search bar is the composer.
@@ -271,7 +263,7 @@ function ChatSession({
       thread.length === 0 ? empty : buildThreadMarkdown(thread, transcriptOptions);
 
     return [...notes, transcript].filter((part) => part.length > 0).join("\n\n");
-  }, [launchNote, snipNote, pending, activity, thread, transcriptOptions]);
+  }, [launchNote, snipNote, pending, thread, transcriptOptions]);
 
   const rows: SessionRow[] = useMemo(() => {
     const base = summaries ?? [];

src/lib/markdown.ts

@@ -1,5 +1,6 @@
 import { imageSource } from "./attachments";
 import { repairCodeBlocks } from "./code";
+import { describeActivity } from "./thread";
 import type { Attachment, ChatTurn, ThreadMessage } from "./types";
 
 /**
@@ -82,17 +83,37 @@ function renderMessage(message: ThreadMessage, options: TranscriptOptions): stri
   }
 
   // While a tool is running there is no answer text yet, so the activity line
-  // stands in and the user can see what Lam is actually doing.
-  const placeholder = message.status ? `_${message.status}…_` : "_Thinking…_";
-  const body = message.text.trim()
+  // stands in and the user can see what Lam is actually doing. It is shown
+  // whether or not tokens have arrived, because a tool that starts after the
+  // answer has begun would otherwise be invisible for the rest of the turn.
+  const activityLine =
+    message.isStreaming && message.activity ? `_${describeActivity(message.activity)}…_` : undefined;
+
+  /** The answer, or whatever stands in for it while there is none. */
+  const answered = message.text.trim();
+  const body = answered
     ? // Fences without a language render as a plain dark panel, and a lone
       // inline command renders as a chip with no Copy button at all. Both are
       // repaired before the markdown reaches the renderer.
-      repairCodeBlocks(message.text.trim())
-    : message.isStreaming
-      ? placeholder
-      : "_No response._";
-  const sections = [message.isStreaming ? `${body} ${STREAMING_CURSOR}` : body];
+      repairCodeBlocks(answered)
+    : !message.isStreaming
+      ? "_No response._"
+      : activityLine
+        ? // The activity line above is already saying what is being waited on, so
+          // printing the placeholder as well put the same sentence on screen
+          // twice: once as a note above the transcript and once as the stand-in.
+          undefined
+        : message.status
+          ? `_${message.status}…_`
+          : "_Thinking…_";
+
+  // The cursor trails whichever of the two is written last, so it always sits at
+  // the end of the text arriving rather than on a line of its own.
+  const written = [activityLine, body].filter((line): line is string => Boolean(line));
+  const last = written.length - 1;
+  const sections = written.map((line, index) =>
+    message.isStreaming && index === last ? `${line} ${STREAMING_CURSOR}` : line,
+  );
 
   // The one thing allowed to break the plain-text rule, because it means
   // something went wrong and should not be skimmed past.

src/lib/thread.ts

@@ -1,4 +1,4 @@
-import type { ChatTurn, ThreadMessage } from "./types";
+import type { ChatTurn, ThreadMessage, ToolActivity } from "./types";
 
 /**
  * Flattens stored turns into the flat message list the transcript renders.
@@ -15,6 +15,20 @@ export interface LiveState {
   thinking: string;
   /** Activity line, e.g. "Searching the web". Only meaningful mid-turn. */
   status?: string;
+  /** The tool being waited on right now, which supersedes the plain status when present. */
+  activity?: ToolActivity;
+}
+
+/**
+ * One line describing a tool that is running.
+ *
+ * Says "the same call again" rather than showing a bare count, because a number
+ * on its own reads as progress. This is the visible half of the loop guard in
+ * `agent.ts`, and the only warning the user gets before a turn is cut short.
+ */
+export function describeActivity(activity: ToolActivity): string {
+  if (activity.count <= 1) return activity.label;
+  return `${activity.label} · the same call again (${activity.count})`;
 }
 
 export function buildThread(turns: ChatTurn[], live: LiveState): ThreadMessage[] {
@@ -43,6 +57,10 @@ export function buildThread(turns: ChatTurn[], live: LiveState): ThreadMessage[]
       // Only while there is nothing to read yet. Once tokens land, the
       // placeholder it feeds is gone anyway.
       status: isLive && text.length === 0 ? live.status : undefined,
+      // The tool, on the other hand, is worth naming even after the answer has
+      // started arriving: a tool that begins mid-answer would otherwise be
+      // invisible, which was the original complaint about hidden tool calls.
+      activity: isLive ? live.activity : undefined,
       // Only a question carries attachments, so the answer never has one.
       attachments: [],
     });

src/lib/types.ts

@@ -158,6 +158,24 @@ export interface SessionSummary {
  */
 export type VisionSupport = "yes" | "no" | "unknown";
 
+/**
+ * The tool running right now, and how stale it is getting.
+ *
+ * Lives here rather than beside the chat state machine so that `thread.ts` can
+ * carry it into the transcript, which is the only place it is now rendered.
+ */
+export interface ToolActivity {
+  /** Human-readable label, e.g. "Searching the web". */
+  label: string;
+  /**
+   * How many times this turn has now started this *identical* call.
+   *
+   * Counted by the agent over name and arguments together, so two different
+   * searches are two tools doing their job rather than a repeat.
+   */
+  count: number;
+}
+
 /** A model as reported by `GET /api/tags`. */
 export interface ModelInfo {
   name: string;
@@ -204,6 +222,16 @@ export interface ThreadMessage {
   error?: string;
   /** Activity line shown while this message is streaming, e.g. "Searching the web". */
   status?: string;
+  /**
+   * The tool this message is waiting on, when there is one.
+   *
+   * Separate from {@link ThreadMessage.status} because the two are rendered from
+   * different triggers: the status is a stand-in used only while there is no text
+   * to read, while a running tool is worth saying whether or not tokens have
+   * started arriving. Carrying both is what lets one line be printed for one
+   * fact, rather than the same sentence appearing twice at the top of a turn.
+   */
+  activity?: ToolActivity;
   /** Images attached to this question. Only ever non-empty on a user message. */
   attachments: Attachment[];
 }