fix: avoid echoing prompts when rpc returns empty

CHANGELOG.md

@@ -14,6 +14,7 @@
 - Tau RPC timeout is now inactivity-based (5m without events) and error messages show seconds only.
 - Directive triggers (`/think`, `/verbose`, `/stop` et al.) now reply immediately using normalized bodies (timestamps/group prefixes stripped) without waiting for the agent.
 - Batched history blocks no longer trip directive parsing; `/think` in prior messages won't emit stray acknowledgements.
+- RPC fallbacks no longer echo the user's prompt (e.g., pasting a link) when the agent returns no assistant text.
 
 ## 1.4.1 — 2025-12-04
 

src/auto-reply/command-reply.test.ts

@@ -111,6 +111,43 @@ describe("runCommandReply (pi)", () => {
     ).toBe(false);
   });
 
+  it("does not echo the user's prompt when the agent returns no assistant text", async () => {
+    const rpcMock = mockPiRpc({
+      stdout: [
+        '{"type":"agent_start"}',
+        '{"type":"turn_start"}',
+        '{"type":"message_start","message":{"role":"user","content":[{"type":"text","text":"hello"}]}}',
+        '{"type":"message_end","message":{"role":"user","content":[{"type":"text","text":"hello"}]}}',
+        // assistant emits nothing useful
+        '{"type":"agent_end"}',
+      ].join("\n"),
+      stderr: "",
+      code: 0,
+    });
+
+    const { payloads } = await runCommandReply({
+      reply: {
+        mode: "command",
+        command: ["pi", "{{Body}}"],
+        agent: { kind: "pi" },
+      },
+      templatingCtx: { ...noopTemplateCtx, Body: "hello", BodyStripped: "hello" },
+      sendSystemOnce: false,
+      isNewSession: true,
+      isFirstTurnInSession: true,
+      systemSent: false,
+      timeoutMs: 1000,
+      timeoutSeconds: 1,
+      commandRunner: vi.fn(),
+      enqueue: enqueueImmediate,
+    });
+
+    expect(rpcMock).toHaveBeenCalledOnce();
+    expect(payloads?.length).toBe(1);
+    expect(payloads?.[0]?.text).toMatch(/no output/i);
+    expect(payloads?.[0]?.text).not.toContain("hello");
+  });
+
   it("adds session args and --continue when resuming", async () => {
     const rpcMock = mockPiRpc({
       stdout:

src/auto-reply/command-reply.ts

@@ -32,6 +32,7 @@ function stripRpcNoise(raw: string): string {
       const type = evt?.type;
       const msg = evt?.message ?? evt?.assistantMessageEvent;
       const msgType = msg?.type;
+      const role = msg?.role;
 
       // RPC streaming emits one message_update per delta; skip them to avoid flooding fallbacks.
       if (type === "message_update") continue;
@@ -40,6 +41,11 @@ function stripRpcNoise(raw: string): string {
       if (type === "message_update" && msgType === "toolcall_delta") continue;
       if (type === "input_audio_buffer.append") continue;
 
+      // Keep only assistant/tool messages; drop agent_start/turn_start/user/etc.
+      const isAssistant = role === "assistant";
+      const isToolRole = typeof role === "string" && role.toLowerCase().includes("tool");
+      if (!isAssistant && !isToolRole) continue;
+
       // Ignore assistant messages that have no text content (pure toolcall scaffolding).
       if (msg?.role === "assistant" && Array.isArray(msg?.content)) {
         const hasText = msg.content.some(
@@ -770,9 +776,15 @@ export async function runCommandReply(
       extractRpcAssistantText(trimmed) ??
       extractAssistantTextLoosely(trimmed) ??
       trimmed;
-    if (replyItems.length === 0 && fallbackText && !hasParsedContent) {
+    const promptEcho =
+      fallbackText &&
+      (fallbackText === (templatingCtx.Body ?? "") ||
+        fallbackText === (templatingCtx.BodyStripped ?? ""));
+    const safeFallbackText = promptEcho ? undefined : fallbackText;
+
+    if (replyItems.length === 0 && safeFallbackText && !hasParsedContent) {
       const { text: cleanedText, mediaUrls: mediaFound } =
-        splitMediaFromOutput(fallbackText);
+        splitMediaFromOutput(safeFallbackText);
       if (cleanedText || mediaFound?.length) {
         replyItems.push({
           text: cleanedText,