diff --git a/crates/app-tauri/src/commands.rs b/crates/app-tauri/src/commands.rs
index d6f65ed..5c16879 100644
--- a/crates/app-tauri/src/commands.rs
+++ b/crates/app-tauri/src/commands.rs
@@ -1064,28 +1064,37 @@ pub async fn launch_agent(
 
     let session_id = output.session.id;
 
-    // Register the xterm output channel for this session.
-    let gen = state.pty_bridge.register(session_id, on_output);
+    // §17.4/§17.6: a structured launch routes to an `AgentSession`, registered
+    // **only** in `StructuredSessions` — its id is never a live PTY. Such a cell is
+    // a chat view driven by `agent_send`/`reattach_agent_chat`, not by xterm bytes,
+    // so we must NOT wire it to the PTY bridge. Doing so would call
+    // `subscribe_output` with an id the PTY adapter has never seen → `NotFound`
+    // ("process error: pty handle not found"), failing every structured agent
+    // launch. Only the raw-PTY path (`structured: None`) gets the byte pump.
+    if output.structured.is_none() {
+        // Register the xterm output channel for this session.
+        let gen = state.pty_bridge.register(session_id, on_output);
 
-    // Subscribe to the PTY's byte stream and pump it to the channel.
-    // The stream is a blocking iterator; it runs on a dedicated OS thread and
-    // ends when the PTY hits EOF or this attach is superseded.
-    let handle = PtyHandle { session_id };
-    match state.pty_port.subscribe_output(&handle) {
-        Ok(stream) => {
-            let bridge: std::sync::Arc<PtyBridge> = std::sync::Arc::clone(&state.pty_bridge);
-            std::thread::spawn(move || {
-                for chunk in stream {
-                    if !bridge.send_output(&session_id, chunk) {
-                        break;
+        // Subscribe to the PTY's byte stream and pump it to the channel.
+        // The stream is a blocking iterator; it runs on a dedicated OS thread and
+        // ends when the PTY hits EOF or this attach is superseded.
+        let handle = PtyHandle { session_id };
+        match state.pty_port.subscribe_output(&handle) {
+            Ok(stream) => {
+                let bridge: std::sync::Arc<PtyBridge> = std::sync::Arc::clone(&state.pty_bridge);
+                std::thread::spawn(move || {
+                    for chunk in stream {
+                        if !bridge.send_output(&session_id, chunk) {
+                            break;
+                        }
                     }
-                }
-                bridge.unregister_if(&session_id, gen);
-            });
-        }
-        Err(e) => {
-            state.pty_bridge.unregister(&session_id);
-            return Err(ErrorDto::from(AppError::from(e)));
+                    bridge.unregister_if(&session_id, gen);
+                });
+            }
+            Err(e) => {
+                state.pty_bridge.unregister(&session_id);
+                return Err(ErrorDto::from(AppError::from(e)));
+            }
         }
     }