diff --git a/src/sounddiff/cli.py b/src/sounddiff/cli.py
index 2355aa9..0b97a19 100644
--- a/src/sounddiff/cli.py
+++ b/src/sounddiff/cli.py
@@ -20,8 +20,8 @@
 
 
 @click.command()
-@click.argument("file_a", type=click.Path(exists=True))
-@click.argument("file_b", type=click.Path(exists=True))
+@click.argument("file_a", type=click.Path())
+@click.argument("file_b", type=click.Path())
 @click.option(
     "--format",
     "output_format",
@@ -65,6 +65,31 @@ def main(
     Compares FILE_A (reference) against FILE_B (comparison) and reports
     differences in loudness, spectral content, timing, and potential issues.
     """
+    console = Console()
+    
+    # Validate file_a
+    path_a = pathlib.Path(file_a)
+    if not path_a.exists():
+        console.print(f"[red]Error:[/red] File not found: [bold]{file_a}[/bold]")
+        console.print(f"[dim]Looked in: {path_a.parent.absolute()}[/dim]")
+        console.print("[dim]Tip: Check the file path and make sure the file exists.[/dim]")
+        sys.exit(1)
+    
+    # Validate file_b
+    path_b = pathlib.Path(file_b)
+    if not path_b.exists():
+        console.print(f"[red]Error:[/red] sounddiff needs two files to compare.")
+        console.print(f"[dim]Got: {file_a} (exists), but {file_b} not found.[/dim]")
+        console.print(f"[dim]Looked in: {path_b.parent.absolute()}[/dim]")
+        sys.exit(1)
+    
+    # Validate audio file extensions
+    audio_extensions = {'.wav', '.mp3', '.flac', '.ogg', '.m4a', '.aac', '.wma', '.aiff', '.aif'}
+    for file_path, arg_name in [(path_a, 'FILE_A'), (path_b, 'FILE_B')]:
+        if file_path.suffix.lower() not in audio_extensions:
+            console.print(f"[yellow]Warning:[/yellow] {arg_name} ('{file_path.name}') may not be an audio file.")
+            console.print(f"[dim]Expected audio formats: {', '.join(sorted(audio_extensions))}[/dim]")
+    
     # Best-effort duration probe: if sf.info() fails for either file,
     # skip the progress bar and let diff() raise the proper error message.
     show_progress = False