docs: align roots terminology with MCP spec clarification (#1469)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: stephentoub <2642209+stephentoub@users.noreply.github.com>

docs/concepts/roots/roots.md

@@ -17,7 +17,7 @@ Roots provide a mechanism for the client to tell the server which directories, p
 
 - Scope file searches to the user's project directories
 - Understand which repositories are being worked on
-- Limit operations to specific filesystem boundaries
+- Focus operations on relevant filesystem locations
 
 Each root is represented by a <xref:ModelContextProtocol.Protocol.Root> with a URI and an optional human-readable name.
 

src/ModelContextProtocol.Core/Protocol/NotificationMethods.cs

@@ -53,9 +53,10 @@ public static class NotificationMethods
     /// <remarks>
     /// <para>
     /// This notification informs the server that the client's "roots" have changed.
-    /// Roots define the boundaries of where servers can operate within the filesystem,
+    /// Roots inform servers about the directories and files the client considers relevant,
-    /// allowing them to understand which directories and files they have access to. Servers
+    /// so that servers can focus their operations accordingly. They are informational guidance
-    /// can request the list of roots from supporting clients and receive notifications when that list changes.
+    /// rather than an access-control mechanism; the protocol does not enforce that servers stay within roots.
+    /// Servers can request the list of roots from supporting clients and receive notifications when that list changes.
     /// </para>
     /// <para>
     /// After receiving this notification, servers can refresh their knowledge of roots by calling the appropriate

src/ModelContextProtocol.Core/Protocol/Root.cs

@@ -9,9 +9,10 @@ namespace ModelContextProtocol.Protocol;
 /// </summary>
 /// <remarks>
 /// Root URIs serve as entry points for resource navigation, typically representing
-/// top-level directories or container resources that can be accessed and traversed.
+/// top-level directories or container resources that are relevant to the current session.
-/// Roots provide a hierarchical structure for organizing and accessing resources within the protocol.
+/// Roots inform servers which locations the client considers important, providing informational
-/// Each root has a URI that uniquely identifies it and optional metadata like a human-readable name.
+/// guidance rather than an access-control mechanism. Each root has a URI that uniquely identifies
+/// it and optional metadata like a human-readable name.
 /// </remarks>
 public sealed class Root
 {

src/ModelContextProtocol.Core/Protocol/RootsCapability.cs

@@ -13,9 +13,9 @@ namespace ModelContextProtocol.Protocol;
 /// root URIs that serve as entry points for resource navigation.
 /// </para>
 /// <para>
-/// The roots capability establishes a mechanism for servers to discover and access the hierarchical
+/// The roots capability establishes a mechanism for servers to discover the directories and files
-/// structure of resources provided by a client. Root URIs represent top-level entry points from which
+/// the client considers relevant. Root URIs represent top-level entry points that inform the server
-/// servers can navigate to access specific resources.
+/// about the working context, providing informational guidance rather than enforcing access control.
 /// </para>
 /// <para>
 /// See the <see href="https://github.com/modelcontextprotocol/specification/blob/main/schema/">schema</see> for details.