Fix: Use absolute path to uv executable in Claude Desktop config (#440)

Author: arcAman07

src/mcp/cli/claude.py

@@ -2,6 +2,7 @@
 
 import json
 import os
+import shutil
 import sys
 from pathlib import Path
 from typing import Any
@@ -30,6 +31,16 @@ def get_claude_config_path() -> Path | None:
         return path
     return None
 
+def get_uv_path() -> str:
+    """Get the full path to the uv executable."""
+    uv_path = shutil.which("uv")
+    if not uv_path:
+        logger.error(
+            "uv executable not found in PATH, falling back to 'uv'. "
+            "Please ensure uv is installed and in your PATH"
+        )
+        return "uv"  # Fall back to just "uv" if not found
+    return uv_path
 
 def update_claude_config(
     file_spec: str,
@@ -54,6 +65,7 @@ def update_claude_config(
             Claude Desktop may not be installed or properly set up.
     """
     config_dir = get_claude_config_path()
+    uv_path = get_uv_path()
     if not config_dir:
         raise RuntimeError(
             "Claude Desktop config directory not found. Please ensure Claude Desktop"
@@ -117,7 +129,7 @@ def update_claude_config(
         # Add fastmcp run command
         args.extend(["mcp", "run", file_spec])
 
-        server_config: dict[str, Any] = {"command": "uv", "args": args}
+        server_config: dict[str, Any] = {"command": uv_path, "args": args}
 
         # Add environment variables if specified
         if env_vars:

tests/client/test_config.py

@@ -48,3 +48,28 @@ def test_command_execution(mock_config_path: Path):
 
     assert result.returncode == 0
     assert "usage" in result.stdout.lower()
+
+
+def test_absolute_uv_path(mock_config_path: Path):
+    """Test that the absolute path to uv is used when available."""
+    # Mock the shutil.which function to return a fake path
+    mock_uv_path = "/usr/local/bin/uv"
+    
+    with patch("mcp.cli.claude.get_uv_path", return_value=mock_uv_path):
+        # Setup
+        server_name = "test_server"
+        file_spec = "test_server.py:app"
+
+        # Update config
+        success = update_claude_config(file_spec=file_spec, server_name=server_name)
+        assert success
+
+        # Read the generated config
+        config_file = mock_config_path / "claude_desktop_config.json"
+        config = json.loads(config_file.read_text())
+
+        # Verify the command is the absolute path
+        server_config = config["mcpServers"][server_name]
+        command = server_config["command"]
+        
+        assert command == mock_uv_path