diff --git a/tools/patman/tools.py b/tools/patman/tools.py
index e804814..0870bcc 100644
--- a/tools/patman/tools.py
+++ b/tools/patman/tools.py
@@ -22,6 +22,10 @@ chroot_path = None
 # Search paths to use for Filename(), used to find files
 search_paths = []
 
+# Tools and the packages that contain them, on debian
+packages = {
+    'lz4': 'liblz4-tool',
+    }
 
 def PrepareOutputDir(dirname, preserve=False):
     """Select an output directory, ensuring it exists.
@@ -128,8 +132,31 @@ def Align(pos, align):
 def NotPowerOfTwo(num):
     return num and (num & (num - 1))
 
+def PathHasFile(fname):
+    """Check if a given filename is in the PATH
+
+    Args:
+        fname: Filename to check
+
+    Returns:
+        True if found, False if not
+    """
+    for dir in os.environ['PATH'].split(':'):
+        if os.path.exists(os.path.join(dir, fname)):
+            return True
+    return False
+
 def Run(name, *args):
-    command.Run(name, *args, cwd=outdir)
+    try:
+        return command.Run(name, *args, cwd=outdir, capture=True)
+    except:
+        if not PathHasFile(name):
+            msg = "Plesae install tool '%s'" % name
+            package = packages.get(name)
+            if package:
+                 msg += " (e.g. from package '%s')" % package
+            raise ValueError(msg)
+        raise
 
 def Filename(fname):
     """Resolve a file path to an absolute path.