diff --git a/src/mcp_obsidian/obsidian.py b/src/mcp_obsidian/obsidian.py
index 3133eb6..4eec13c 100644
--- a/src/mcp_obsidian/obsidian.py
+++ b/src/mcp_obsidian/obsidian.py
@@ -84,10 +84,19 @@ class Obsidian():
             host = parsed.hostname or '127.0.0.1'
             port = parsed.port or (27124 if protocol == 'https' else 27123)
         else:
-            # Legacy hostname/IP only format
-            protocol = 'https'
-            host = host_config
-            port = 27124
+            # Support legacy formats
+            # 1) hostname/IP only
+            # 2) hostname:port (no protocol)
+            if ':' in host_config:
+                # Treat as host:port and default protocol to https
+                parsed = urlparse(f'https://{host_config}')
+                protocol = 'https'
+                host = parsed.hostname or '127.0.0.1'
+                port = parsed.port or 27124
+            else:
+                protocol = 'https'
+                host = host_config
+                port = 27124
             
         return protocol, host, port