Merge branch 'master' into eugene/experimenting_with_layout

docs/docs/concepts/index.mdx

@@ -1,9 +1,16 @@
+---
+sidebar_position: 0
+sidebar_class_name: hidden
+---
+
 # Conceptual guide
 
 import ThemedImage from '@theme/ThemedImage';
 import useBaseUrl from '@docusaurus/useBaseUrl';
 
-This section contains introductions to key parts of LangChain.
+In this section, you'll find explanations of the key concepts, providing a deeper understanding of core principles.
+
+The conceptual guide will not cover step-by-step instructions or specific implementation details — those are found in the [How-To Guides](/docs/how_to/) and [Tutorials](/docs/tutorials) sections. For detailed reference material, please visit the [API Reference](https://python.langchain.com/api_reference/).
 
 ## Architecture
 

docs/sidebars.js

@@ -47,7 +47,17 @@ module.exports = {
         className: 'hidden',
       }],
     },
-    "concepts",
+    {
+      type: "category",
+      link: {type: 'doc', id: 'concepts/index'},
+      label: "Conceptual Guide",
+      collapsible: false,
+      items: [{
+        type: 'autogenerated',
+        dirName: 'concepts',
+        className: 'hidden',
+      }],
+    },
     {
       type: "category",
       label: "Ecosystem",