diff --git a/lib/types/basemap.ts b/lib/types/basemap.ts
index 9de1d01..9d6fe20 100644
--- a/lib/types/basemap.ts
+++ b/lib/types/basemap.ts
@@ -1,29 +1,44 @@
 import { Type } from '@sinclair/typebox';
 
+/**
+ * Type Schema for Basemap Map Source Configuration
+ * Compatible with Mobile Atlas Creator (MOBAC) Custom XML Map Sources
+ * @link https://mobac.sourceforge.io/wiki/index.php/Custom_XML_Map_Sources
+ */
+
 export const BasemapMapSource = Type.Object({
     name: Type.Object({
         _text: Type.String()
-    }),
+    }, { description: 'The name of the map source' }),
     minZoom: Type.Object({
         _text: Type.Integer()
-    }),
+    }, { description: 'The minimum zoom level provided by the map source' }),
     maxZoom: Type.Object({
         _text: Type.Integer()
-    }),
+    }, { description: 'The maximum zoom level provided by the map source' }),
     tileType: Type.Object({
         _text: Type.String()
-    }),
+    }, { description: 'The image type provided by the map source' }),
     tileUpdate: Type.Optional(Type.Object({
         _text: Type.String({
             default: 'None'
         })
-    })),
+    }, { description: 'The server capabilities for conditional downloading of new/updated tiles' })),
     url: Type.Optional(Type.Object({
         _text: Type.String()
-    })),
+    }, { description: 'The URL for the tiles of the map source' })),
+    invertYCoordinate: Type.Optional(Type.Object({
+        _text: Type.String()
+    }, { description: 'Inverts the y coordinate so that it starts south' })),
     backgroundColor: Type.Optional(Type.Object({
         _text: Type.String()
-    })),
+    }, { description: 'The background color of a map' })),
+    ignoreErrors: Type.Optional(Type.Object({
+        _text: Type.Boolean()
+    }, { description: 'Handling of missing tiles' })),
+    serverParts: Type.Optional(Type.Object({
+        _text: Type.Optional(Type.String())
+    }, { description: 'Use multiple servers for the map source' }))
 })
 
 export default Type.Object({
diff --git a/lib/xml/basemap.ts b/lib/xml/basemap.ts
index 01c9ee7..3bcfde1 100644
--- a/lib/xml/basemap.ts
+++ b/lib/xml/basemap.ts
@@ -33,10 +33,11 @@ export class Basemap extends XMLDocument<BasemapType> {
         tileType: string | undefined;
         tileUpdate: string | undefined;
         backgroundColor: string | undefined;
+        serverParts: string | undefined;
     } {
         if (!this.raw.customMapSource) throw new Err(400, null, 'Unknown Basemap Type');
         if (!this.raw.customMapSource.url) throw new Err(400, null, 'Unknown Basemap Type - Missing URL');
-    
+
         return {
             name: this.raw.customMapSource.name ? this.raw.customMapSource.name._text : undefined,
             url: this.raw.customMapSource.url._text,
@@ -44,7 +45,8 @@ export class Basemap extends XMLDocument<BasemapType> {
             maxZoom: this.raw.customMapSource.maxZoom ? Number(this.raw.customMapSource.maxZoom._text) : undefined,
             tileType: this.raw.customMapSource.tileType ? this.raw.customMapSource.tileType._text : undefined,
             tileUpdate: this.raw.customMapSource.tileUpdate ? this.raw.customMapSource.tileUpdate._text : undefined,
-            backgroundColor: this.raw.customMapSource.backgroundColor ? this.raw.customMapSource.backgroundColor._text : undefined
+            backgroundColor: this.raw.customMapSource.backgroundColor ? this.raw.customMapSource.backgroundColor._text : undefined,
+            serverParts: this.raw.customMapSource.serverParts ? this.raw.customMapSource.serverParts._text : undefined,
         }
     }
 }
diff --git a/test/basemaps.test.ts b/test/basemaps.test.ts
index 6b9013f..e9ca690 100644
--- a/test/basemaps.test.ts
+++ b/test/basemaps.test.ts
@@ -9,10 +9,25 @@ for (const fixturename of await fs.readdir(new URL('./basemaps/', import.meta.ur
         const fixture = String(await fs.readFile(path.join(path.parse(fileURLToPath(import.meta.url)).dir, 'basemaps/', fixturename)));
         const container = await Basemap.parse(fixture);
 
-        t.ok(container.raw.customMapSource.name._text.length)
+        t.ok(container.raw.customMapSource.name._text.length, 'Ensure raw xml name exists')
 
         const json = container.to_json();
-        t.ok(json.name && json.name.length);
+        t.ok(json.name && json.name.length, 'Ensure JSON name exists');
+        t.ok(json.url && json.url.length, 'Ensure JSON url exists');
+        t.ok(typeof json.minZoom === 'number', 'Ensure JSON minZoom is a number');
+        t.ok(typeof json.maxZoom === 'number', 'Ensure JSON maxZoom is a number');
+        t.ok(typeof json.tileType === 'string' && json.tileType.length, 'Ensure JSON tileType is a string');
+        
+        t.deepEqual(Object.keys(json), [
+            'name',
+            'url',
+            'minZoom',
+            'maxZoom',
+            'tileType',
+            'tileUpdate',
+            'backgroundColor',
+            'serverParts'
+        ], 'Ensure JSON keys match expected structure')
 
         t.end();
     });
diff --git a/test/basemaps/opentopomap.xml b/test/basemaps/opentopomap.xml
index 7539c71..5d880f9 100644
--- a/test/basemaps/opentopomap.xml
+++ b/test/basemaps/opentopomap.xml
@@ -7,4 +7,4 @@
     <tileUpdate>IfNoneMatch</tileUpdate>
     <serverParts>a b c</serverParts>
     <url>https://{$serverpart}.tile.opentopomap.org/{$z}/{$x}/{$y}.png</url>
-</customMapSource>
\ No newline at end of file
+</customMapSource>