diff --git a/xml/System.Runtime.Versioning/SupportedOSPlatformAttribute.xml b/xml/System.Runtime.Versioning/SupportedOSPlatformAttribute.xml
index 283fb87abe3..c0d7ecab1b8 100644
--- a/xml/System.Runtime.Versioning/SupportedOSPlatformAttribute.xml
+++ b/xml/System.Runtime.Versioning/SupportedOSPlatformAttribute.xml
@@ -20,8 +20,17 @@
     </Attribute>
   </Attributes>
   <Docs>
-    <summary>To be added.</summary>
-    <remarks>To be added.</remarks>
+    <summary>Indicates that an API is supported for a specified platform or operating system. If a version is specified, the API cannot be called from an earlier version. Multiple attributes can be applied to indicate support on multiple operating systems.</summary>
+    <remarks>
+      <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+Callers can apply a <xref:System.Runtime.Versioning.SupportedOSPlatformAttribute> or use guards to prevent calls to APIs on unsupported operating systems.
+             A given platform should only be specified once.
+
+          ]]></format>
+    </remarks>
   </Docs>
   <Members>
     <Member MemberName=".ctor">
@@ -40,8 +49,8 @@
         <Parameter Name="platformName" Type="System.String" />
       </Parameters>
       <Docs>
-        <param name="platformName">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="platformName">The supported OS platform name, optionally including a version.</param>
+        <summary>Initializes a new instance of the <see cref="T:System.Runtime.Versioning.SupportedOSPlatformAttribute" /> attribute class for the specified supported OS platform.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
diff --git a/xml/System.Runtime.Versioning/TargetPlatformAttribute.xml b/xml/System.Runtime.Versioning/TargetPlatformAttribute.xml
index 924c35f96d0..d8600e7d751 100644
--- a/xml/System.Runtime.Versioning/TargetPlatformAttribute.xml
+++ b/xml/System.Runtime.Versioning/TargetPlatformAttribute.xml
@@ -40,8 +40,8 @@
         <Parameter Name="platformName" Type="System.String" />
       </Parameters>
       <Docs>
-        <param name="platformName">To be added.</param>
-        <summary>Initializes a new instance of the <see cref="T:System.Runtime.Versioning.TargetPlatformAttribute" /> class.</summary>
+        <param name="platformName">The target OS platform name.</param>
+        <summary>Initializes a new instance of the <see cref="T:System.Runtime.Versioning.TargetPlatformAttribute" /> attribute class for the specified target OS platform.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
diff --git a/xml/System.Runtime.Versioning/UnsupportedOSPlatformAttribute.xml b/xml/System.Runtime.Versioning/UnsupportedOSPlatformAttribute.xml
index 1fd772d23f5..58de7359ba6 100644
--- a/xml/System.Runtime.Versioning/UnsupportedOSPlatformAttribute.xml
+++ b/xml/System.Runtime.Versioning/UnsupportedOSPlatformAttribute.xml
@@ -20,8 +20,16 @@
     </Attribute>
   </Attributes>
   <Docs>
-    <summary>To be added.</summary>
-    <remarks>To be added.</remarks>
+    <summary>Marks APIs that were removed or are unsupported in a given operating system version.</summary>
+    <remarks>
+      <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+The versionless attribute is primarily used to indicate the API is unsupported for the platform. If a version is specified, the API is only available in earlier versions.
+
+          ]]></format>
+    </remarks>
   </Docs>
   <Members>
     <Member MemberName=".ctor">
@@ -40,8 +48,8 @@
         <Parameter Name="platformName" Type="System.String" />
       </Parameters>
       <Docs>
-        <param name="platformName">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="platformName">The unsupported OS platform name, optionally including a version.</param>
+        <summary>Initializes a new instance of the <see cref="T:System.Runtime.Versioning.UnsupportedOSPlatformAttribute" /> attribute class for the specified unsupported OS platform.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>