diff --git a/scripts/review_pr.py b/scripts/review_pr.py
index fca864a..ccb6aa6 100644
--- a/scripts/review_pr.py
+++ b/scripts/review_pr.py
@@ -19,6 +19,7 @@ import shutil
 import subprocess
 import sys
 import threading
+import time
 import urllib.error
 import urllib.request
 
@@ -327,7 +328,7 @@ def run_claude(claude_bin, project_root, prompt, extra_dir=None):
         cmd += ["--add-dir", extra_dir]
     cmd.append(prompt)
 
-    print(f"[review_pr] Running: {' '.join(cmd[:4])} ...", file=sys.stderr)
+    print(f"[review_pr] Command: {' '.join(cmd)}", file=sys.stderr)
     proc = subprocess.Popen(
         cmd,
         cwd=project_root,
@@ -337,22 +338,37 @@ def run_claude(claude_bin, project_root, prompt, extra_dir=None):
         encoding="utf-8",
     )
 
-    def _stream(pipe, label, dest_lines):
+    def _stream(pipe, prefix, dest_lines):
         for line in pipe:
             line = line.rstrip("\n")
-            if line:
-                print(f"[{label}] {line}", file=sys.stderr)
             dest_lines.append(line)
-
-    stderr_lines = []
-    t = threading.Thread(target=_stream, args=(proc.stderr, "claude:stderr", stderr_lines))
-    t.start()
+            if line.strip():
+                print(f"[{prefix}] {line}", file=sys.stderr)
 
     stdout_lines = []
-    _stream(proc.stdout, "claude", stdout_lines)
+    stderr_lines = []
 
-    t.join(timeout=10)
-    proc.wait(timeout=600)
+    # Heartbeat: print alive message every 30s so we know claude hasn't hung
+    heartbeat_stop = threading.Event()
+    def _heartbeat(start):
+        while not heartbeat_stop.is_set():
+            heartbeat_stop.wait(30)
+            if not heartbeat_stop.is_set():
+                elapsed = int(time.time() - start)
+                print(f"[review_pr] ... still running ({elapsed}s elapsed)", file=sys.stderr)
+    t_beat = threading.Thread(target=_heartbeat, args=(time.time(),))
+    t_beat.start()
+
+    t_out = threading.Thread(target=_stream, args=(proc.stdout, "claude", stdout_lines))
+    t_err = threading.Thread(target=_stream, args=(proc.stderr, "claude:stderr", stderr_lines))
+    t_out.start()
+    t_err.start()
+
+    t_out.join(timeout=600)
+    heartbeat_stop.set()
+    t_err.join(timeout=10)
+    t_beat.join(timeout=5)
+    proc.wait(timeout=10)
 
     if proc.returncode != 0:
         print(f"Claude exited with code {proc.returncode}", file=sys.stderr)
@@ -367,7 +383,7 @@ def extract_json_from_output(stdout):
     match = re.search(r"```json\s*([\s\S]*)\s*```", stdout)
     if not match:
         print("ERROR: No ```json block found in Claude output.", file=sys.stderr)
-        print(stdout[:3000], file=sys.stderr)
+        print(stdout[-3000:], file=sys.stderr)
         sys.exit(1)
 
     try: