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

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: [],
     });