fix(cli): print friendly error instead of traceback when proxy is unreachable

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

litellm/proxy/client/cli/main.py

@@ -3,6 +3,7 @@ from typing import Optional
 
 # third party imports
 import click
+import requests
 
 from litellm._version import version as litellm_version
 from litellm.proxy.client.health import HealthManagementClient
@@ -22,6 +23,20 @@ from .commands.users import users
 from .interface import interactive_shell
 
 
+class ConnectionAwareGroup(click.Group):
+    def invoke(self, ctx: click.Context) -> object:
+        try:
+            return super().invoke(ctx)
+        except requests.exceptions.ConnectionError as e:
+            base_url = ctx.obj.get("base_url") if isinstance(ctx.obj, dict) else None
+            target = f" at {base_url}" if base_url else ""
+            raise click.ClickException(
+                f"Could not connect to the LiteLLM proxy{target}. "
+                "Make sure the server is running and reachable, or point the CLI at it "
+                "with --base-url or the LITELLM_PROXY_URL environment variable."
+            ) from e
+
+
 def print_version(base_url: str, api_key: Optional[str]):
     """Print CLI and server version info."""
     click.echo(f"LiteLLM Proxy CLI Version: {litellm_version}")
@@ -38,7 +53,7 @@ def print_version(base_url: str, api_key: Optional[str]):
         click.echo(f"Could not retrieve server version: {e}")
 
 
-@click.group(invoke_without_command=True)
+@click.group(cls=ConnectionAwareGroup, invoke_without_command=True)
 @click.option(
     "--version",
     "-v",

tests/test_litellm/proxy/client/cli/test_global_options.py

@@ -4,6 +4,7 @@ import sys
 from unittest.mock import Mock, patch
 
 import pytest
+import requests
 from click.testing import CliRunner
 
 sys.path.insert(
@@ -65,6 +66,30 @@ def test_base_url_trailing_slash_normalized(cli_runner):
     )
 
 
+@pytest.mark.parametrize(
+    "args",
+    [
+        ["models", "list"],
+        ["keys", "list"],
+        ["http", "request", "GET", "/models"],
+    ],
+)
+def test_connection_error_prints_friendly_message(cli_runner, args):
+    """A dead proxy must yield a friendly 'Error:' line and exit 1, not a raw traceback."""
+    base_url = "http://127.0.0.1:59999"
+    with patch(
+        "requests.sessions.Session.request",
+        side_effect=requests.exceptions.ConnectionError("connection refused"),
+    ):
+        result = cli_runner.invoke(cli, ["--base-url", base_url, *args])
+
+    assert result.exit_code == 1
+    assert "Traceback" not in result.output
+    assert f"Could not connect to the LiteLLM proxy at {base_url}" in result.output
+    # The exception must be swallowed into a click exit, never surfaced raw.
+    assert not isinstance(result.exception, requests.exceptions.ConnectionError)
+
+
 def test_cli_version_command(cli_runner):
     """Test that 'version' command prints the correct version, server URL, and server version, and exits successfully"""
     with (