diff --git a/src/libraries/System.CodeDom/src/PACKAGE.md b/src/libraries/System.CodeDom/src/PACKAGE.md
new file mode 100644
index 0000000000000..2785a3e5888a3
--- /dev/null
+++ b/src/libraries/System.CodeDom/src/PACKAGE.md
@@ -0,0 +1,127 @@
+## About
+
+<!-- A description of the package and where one can find more documentation -->
+
+Provides functionality for dynamically generating and compiling source code using the Code Document Object Model (CodeDOM).
+
+It allows developers to represent code in a language-agnostic format and then generate code in multiple languages, such as C# and VB.NET.
+The primary use cases include creating dynamic code generation tools, runtime code generation, and facilitating code analysis or transformation.
+
+For a new modern development consider using the [.NET Compiler Platform SDK](https://learn.microsoft.com/dotnet/csharp/roslyn-sdk/), in particular [Roslyn source generators](https://learn.microsoft.com/dotnet/csharp/roslyn-sdk/source-generators-overview#get-started-with-source-generators).
+
+## Key Features
+
+<!-- The key features of this package -->
+
+* Write code using a common object model that can be translated into multiple programming languages.
+* Generate and compile code at runtime based on the CodeDOM.
+
+## How to Use
+
+<!-- A compelling example on how to use this package with code, as well as any specific guidelines for when to use the package -->
+
+Generating and compiling C# code:
+
+```csharp
+using System.CodeDom;
+using System.CodeDom.Compiler;
+using Microsoft.CSharp;
+
+// Create a new CodeCompileUnit to hold the code
+var compileUnit = new CodeCompileUnit();
+
+// Create a namespace
+var codeNamespace = new CodeNamespace("MyNamespace");
+compileUnit.Namespaces.Add(codeNamespace);
+
+// Create a class
+var classDeclaration = new CodeTypeDeclaration("MyClass")
+{
+    IsClass = true
+};
+codeNamespace.Types.Add(classDeclaration);
+
+// Add a simple method to the class
+var method = new CodeMemberMethod
+{
+    Name = "HelloWorld",
+    ReturnType = new CodeTypeReference(typeof(void)),
+};
+classDeclaration.Members.Add(method);
+
+var methodInvocation = new CodeMethodInvokeExpression(new CodeTypeReferenceExpression("Console"),
+                                                      "WriteLine",
+                                                      new CodePrimitiveExpression("Hello, World!"));
+method.Statements.Add(methodInvocation);
+
+// Generate C# code from the CodeDOM structure
+CodeDomProvider provider = new CSharpCodeProvider();
+
+using (var writer = new StringWriter())
+{
+    var codeGenereationOptions = new CodeGeneratorOptions()
+    {
+        BlankLinesBetweenMembers = false,
+        IndentString = "  ",
+    };
+
+    provider.GenerateCodeFromCompileUnit(compileUnit, writer, codeGenereationOptions);
+    Console.WriteLine(writer.GetStringBuilder().ToString());
+}
+```
+
+This example generates:
+
+```csharp
+//------------------------------------------------------------------------------
+// <auto-generated>
+//     This code was generated by a tool.
+//
+//     Changes to this file may cause incorrect behavior and will be lost if
+//     the code is regenerated.
+// </auto-generated>
+//------------------------------------------------------------------------------
+
+namespace MyNamespace {
+
+  public class MyClass {
+    private void HelloWorld() {
+      Console.WriteLine("Hello, World!");
+    }
+  }
+}
+```
+
+## Main Types
+
+<!-- The main types provided in this library -->
+
+The main types provided by this library are:
+
+* `System.CodeDom.CodeObject`
+* `System.CodeDom.CodeCompileUnit`
+* `System.CodeDom.CodeNamespace`
+* `System.CodeDom.CodeTypeDeclaration`
+* `System.CodeDom.CodeMemberMethod`
+* `System.CodeDom.CodeTypeReference`
+* `System.CodeDom.CodeMethodInvokeExpression`
+* `System.CodeDom.CodeTypeReferenceExpression`
+* `System.CodeDom.CodePrimitiveExpression`
+* `System.CodeDom.Compiler.CodeDomProvider`
+* `System.CodeDom.Compiler.CodeGeneratorOptions`
+* `Microsoft.CSharp.CSharpCodeProvider`
+* `Microsoft.VisualBasic.VBCodeProvider`
+
+## Additional Documentation
+
+<!-- Links to further documentation. Remove conceptual documentation if not available for the library. -->
+
+* [API documentation](https://learn.microsoft.com/dotnet/api/system.codedom)
+* [Compile and generate dynamic source code](https://learn.microsoft.com/dotnet/framework/reflection-and-codedom/dynamic-source-code-generation-and-compilation)
+
+## Feedback & Contributing
+
+<!-- How to provide feedback on this package and contribute to it -->
+
+System.CodeDom is released as open source under the [MIT license](https://licenses.nuget.org/MIT).
+Bug reports and contributions are welcome at [the GitHub repository](https://github.com/dotnet/runtime).
diff --git a/src/libraries/System.CodeDom/src/System.CodeDom.csproj b/src/libraries/System.CodeDom/src/System.CodeDom.csproj
index a987278ff0539..76ba0e1a9d3f6 100644
--- a/src/libraries/System.CodeDom/src/System.CodeDom.csproj
+++ b/src/libraries/System.CodeDom/src/System.CodeDom.csproj
@@ -6,19 +6,11 @@
     <IsTrimmable>false</IsTrimmable>
     <UseCompilerGeneratedDocXmlFile>false</UseCompilerGeneratedDocXmlFile>
     <IsPackable>true</IsPackable>
-    <PackageDescription>Provides types that can be used to model the structure of a source code document and to output source code for that model in a supported language.
-
-Commonly Used Types:
-System.CodeDom.CodeObject
-System.CodeDom.Compiler.CodeDomProvider
-Microsoft.CSharp.CSharpCodeProvider
-Microsoft.VisualBasic.VBCodeProvider</PackageDescription>
+    <PackageDescription>Provides types that can be used to model the structure of a source code document and to output source code for that model in C# or Visual Basic.</PackageDescription>
 
     <!-- TODO https://github.com/dotnet/runtime/issues/90400: Annotate for nullable reference types -->
     <Nullable>disable</Nullable>
     <NoWarn>$(NoWarn);nullable</NoWarn>
-    <!-- TODO: Add package README file: https://github.com/dotnet/runtime/issues/99358 -->
-    <EnableDefaultPackageReadmeFile>false</EnableDefaultPackageReadmeFile>
   </PropertyGroup>
 
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
diff --git a/src/libraries/System.Composition.AttributedModel/src/PACKAGE.md b/src/libraries/System.Composition.AttributedModel/src/PACKAGE.md
new file mode 100644
index 0000000000000..57bbc8bf0329b
--- /dev/null
+++ b/src/libraries/System.Composition.AttributedModel/src/PACKAGE.md
@@ -0,0 +1,140 @@
+## About
+
+<!-- A description of the package and where one can find more documentation -->
+
+`System.Composition.AttributedModel` is part of the Managed Extensibility Framework (MEF) 2.0, a composition library for .NET that enables dependency injection through attributes or conventions.
+
+This package provides the foundational attributes that allow you to declare parts for composition, such as imports, exports, and metadata.
+It is used to mark classes, properties, methods, and constructors for MEF's discovery and composition process.
+
+## Key Features
+
+<!-- The key features of this package -->
+
+* Provides attributes for declaring composable parts, importing dependencies, metadata, and creating shared or non-shared parts
+
+## How to Use
+
+<!-- A compelling example on how to use this package with code, as well as any specific guidelines for when to use the package -->
+
+Mark classes for export and import using attributes.
+
+```csharp
+using System.Composition;
+using System.Composition.Hosting;
+
+var configuration = new ContainerConfiguration()
+    .WithPart<Service>()
+    .WithPart<Application>();
+
+using CompositionHost container = configuration.CreateContainer();
+
+Application app = container.GetExport<Application>();
+app.Service.Execute();
+// Service is running!
+
+[Export]
+public class Application
+{
+    [Import]
+    public Service Service { get; set; }
+}
+
+[Export]
+public class Service
+{
+    public void Execute() => Console.WriteLine("Service is running!");
+}
+```
+
+Metadata can be used to differentiate between multiple exports of the same contract.
+
+```csharp
+using System.Composition;
+using System.Composition.Hosting;
+
+ContainerConfiguration configuration = new ContainerConfiguration()
+    .WithPart<FileLogger>()
+    .WithPart<ConsoleLogger>()
+    .WithPart<Application>();
+
+using CompositionHost container = configuration.CreateContainer();
+
+Application app = container.GetExport<Application>();
+app.Run();
+// Using FileLogger to log.
+// FileLogger: Hello, World!
+// Using ConsoleLogger to log.
+// ConsoleLogger: Hello, World!
+
+public interface ILogger
+{
+    void Log(string message);
+}
+
+[Export(typeof(ILogger))]
+[ExportMetadata("Name", "FileLogger")]
+public class FileLogger : ILogger
+{
+    public void Log(string message) => Console.WriteLine($"FileLogger: {message}");
+}
+
+[Export(typeof(ILogger))]
+[ExportMetadata("Name", "ConsoleLogger")]
+public class ConsoleLogger : ILogger
+{
+    public void Log(string message) => Console.WriteLine($"ConsoleLogger: {message}");
+}
+
+[Export]
+public class Application
+{
+    [ImportMany]
+    public required IEnumerable<Lazy<ILogger, IDictionary<string, object>>> Loggers { get; set; }
+
+    public void Run()
+    {
+        foreach (var logger in Loggers)
+        {
+            var name = logger.Metadata["Name"];
+
+            Console.WriteLine($"Using {name} to log.");
+            logger.Value.Log("Hello, World!");
+        }
+    }
+}
+```
+
+## Main Types
+
+<!-- The main types provided in this library -->
+
+The main types provided by this library are:
+
+* `System.Composition.ExportAttribute`
+* `System.Composition.ImportAttribute`
+* `System.Composition.ExportMetadataAttribute`
+
+## Additional Documentation
+
+<!-- Links to further documentation. Remove conceptual documentation if not available for the library. -->
+
+* [API documentation](https://learn.microsoft.com/dotnet/api/system.composition)
+* [Managed Extensibility Framework (MEF)](https://learn.microsoft.com/dotnet/framework/mef/)
+
+## Related Packages
+
+<!-- The related packages associated with this package -->
+
+* [System.Composition](https://www.nuget.org/packages/System.Composition)
+* [System.Composition.Convention](https://www.nuget.org/packages/System.Composition.Convention)
+* [System.Composition.Hosting](https://www.nuget.org/packages/System.Composition.Hosting)
+* [System.Composition.Runtime](https://www.nuget.org/packages/System.Composition.Runtime)
+* [System.Composition.TypedParts](https://www.nuget.org/packages/System.Composition.TypedParts)
+
+## Feedback & Contributing
+
+<!-- How to provide feedback on this package and contribute to it -->
+
+System.Composition.AttributedModel is released as open source under the [MIT license](https://licenses.nuget.org/MIT).
+Bug reports and contributions are welcome at [the GitHub repository](https://github.com/dotnet/runtime).
diff --git a/src/libraries/System.Composition.AttributedModel/src/System.Composition.AttributedModel.csproj b/src/libraries/System.Composition.AttributedModel/src/System.Composition.AttributedModel.csproj
index 21e5bd32d21de..44856544cf5dd 100644
--- a/src/libraries/System.Composition.AttributedModel/src/System.Composition.AttributedModel.csproj
+++ b/src/libraries/System.Composition.AttributedModel/src/System.Composition.AttributedModel.csproj
@@ -5,17 +5,10 @@
     <StrongNameKeyId>Microsoft</StrongNameKeyId>
     <UseCompilerGeneratedDocXmlFile>false</UseCompilerGeneratedDocXmlFile>
     <IsPackable>true</IsPackable>
-    <PackageDescription>Provides common attributes used by System.Composition types.
-
-Commonly Used Types:
-System.Composition.ExportAttribute
-System.Composition.ImportAttribute
-System.Composition.Convention.AttributedModelProvider</PackageDescription>
+    <PackageDescription>Provides the foundational attributes that allow you to declare parts for composition, such as imports, exports, and metadata with the Managed Extensibility Framework (MEF).</PackageDescription>
     <!-- TODO https://github.com/dotnet/runtime/issues/90400: Annotate for nullable reference types -->
     <Nullable>disable</Nullable>
     <NoWarn>$(NoWarn);nullable</NoWarn>
-    <!-- TODO: Add package README file: https://github.com/dotnet/runtime/issues/99358 -->
-    <EnableDefaultPackageReadmeFile>false</EnableDefaultPackageReadmeFile>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/src/libraries/System.Composition.Convention/src/PACKAGE.md b/src/libraries/System.Composition.Convention/src/PACKAGE.md
new file mode 100644
index 0000000000000..4f6e1fdc2358c
--- /dev/null
+++ b/src/libraries/System.Composition.Convention/src/PACKAGE.md
@@ -0,0 +1,97 @@
+## About
+
+<!-- A description of the package and where one can find more documentation -->
+
+`System.Composition.Convention` is part of the Managed Extensibility Framework (MEF) 2.0, a composition library for .NET that enables dependency injection through attributes or conventions.
+
+This package simplifies the process of applying consistent patterns for part exports, imports, and metadata by using convention-based configurations.
+It is useful for scenarios where you want to avoid repetitive attribute-based decoration and instead define conventions for registering types in your composition container.
+
+## Key Features
+
+<!-- The key features of this package -->
+
+* Configure exports, imports, and metadata for parts using conventions rather than attributes.
+* Allows defining conventions through a fluent API, making configuration more flexible and readable.
+
+## How to Use
+
+<!-- A compelling example on how to use this package with code, as well as any specific guidelines for when to use the package -->
+
+Configure parts for composition without using attributes.
+
+```csharp
+using System.Composition.Convention;
+using System.Composition.Hosting;
+
+var conventions = new ConventionBuilder();
+
+// Apply conventions: any class that implements ILogger will be exported as ILogger
+conventions
+    .ForTypesDerivedFrom<ILogger>()
+    .Export<ILogger>();
+
+var configuration = new ContainerConfiguration()
+    .WithPart<FileLogger>(conventions)
+    .WithPart<ConsoleLogger>(conventions);
+
+using CompositionHost container = configuration.CreateContainer();
+    
+var loggers = container.GetExports<ILogger>();
+
+foreach (var logger in loggers)
+{
+    logger.Log("Hello, World!");
+}
+// FileLogger: Hello, World!
+// ConsoleLogger: Hello, World!
+
+public interface ILogger
+{
+    void Log(string message);
+}
+
+public class FileLogger : ILogger
+{
+    public void Log(string message) => Console.WriteLine($"FileLogger: {message}");
+}
+
+public class ConsoleLogger : ILogger
+{
+    public void Log(string message) => Console.WriteLine($"ConsoleLogger: {message}");
+}
+```
+
+## Main Types
+
+<!-- The main types provided in this library -->
+
+The main types provided by this library are:
+
+* `System.Composition.Convention.ConventionBuilder`
+* `System.Composition.Convention.PartConventionBuilder`
+* `System.Composition.Convention.ParameterImportConventionBuilder`
+
+## Additional Documentation
+
+<!-- Links to further documentation. Remove conceptual documentation if not available for the library. -->
+
+* [API documentation](https://learn.microsoft.com/dotnet/api/system.composition.convention)
+* [Managed Extensibility Framework (MEF)](https://learn.microsoft.com/dotnet/framework/mef/)
+
+## Related Packages
+
+<!-- The related packages associated with this package -->
+
+* [System.Composition](https://www.nuget.org/packages/System.Composition)
+* [System.Composition.AttributedModel](https://www.nuget.org/packages/System.Composition.AttributedModel)
+* [System.Composition.Hosting](https://www.nuget.org/packages/System.Composition.Hosting)
+* [System.Composition.Runtime](https://www.nuget.org/packages/System.Composition.Runtime)
+* [System.Composition.TypedParts](https://www.nuget.org/packages/System.Composition.TypedParts)
+
+## Feedback & Contributing
+
+<!-- How to provide feedback on this package and contribute to it -->
+
+System.Composition.Convention is released as open source under the [MIT license](https://licenses.nuget.org/MIT).
+Bug reports and contributions are welcome at [the GitHub repository](https://github.com/dotnet/runtime).
diff --git a/src/libraries/System.Composition.Convention/src/System.Composition.Convention.csproj b/src/libraries/System.Composition.Convention/src/System.Composition.Convention.csproj
index 8e1f44ee3df72..2544944eec76e 100644
--- a/src/libraries/System.Composition.Convention/src/System.Composition.Convention.csproj
+++ b/src/libraries/System.Composition.Convention/src/System.Composition.Convention.csproj
@@ -6,19 +6,10 @@
     <StrongNameKeyId>Microsoft</StrongNameKeyId>
     <UseCompilerGeneratedDocXmlFile>false</UseCompilerGeneratedDocXmlFile>
     <IsPackable>true</IsPackable>
-    <PackageDescription>Provides types that support using Managed Extensibility Framework with a convention-based configuration model.
-
-Commonly Used Types:
-System.Composition.Convention.ConventionBuilder
-System.Composition.Convention.ExportConventionBuilder
-System.Composition.Convention.ImportConventionBuilder
-System.Composition.Convention.PartConventionBuilder
-System.Composition.Convention.ParameterImportConventionBuilder</PackageDescription>
+    <PackageDescription>Provides types that support using Managed Extensibility Framework (MEF) with a convention-based configuration model.</PackageDescription>
     <!-- TODO https://github.com/dotnet/runtime/issues/90400: Annotate for nullable reference types -->
     <Nullable>disable</Nullable>
     <NoWarn>$(NoWarn);nullable</NoWarn>
-    <!-- TODO: Add package README file: https://github.com/dotnet/runtime/issues/99358 -->
-    <EnableDefaultPackageReadmeFile>false</EnableDefaultPackageReadmeFile>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/src/libraries/System.Composition.Hosting/src/PACKAGE.md b/src/libraries/System.Composition.Hosting/src/PACKAGE.md
new file mode 100644
index 0000000000000..9f5556e7a4d7b
--- /dev/null
+++ b/src/libraries/System.Composition.Hosting/src/PACKAGE.md
@@ -0,0 +1,80 @@
+## About
+
+<!-- A description of the package and where one can find more documentation -->
+
+`System.Composition.Hosting` is part of the Managed Extensibility Framework (MEF) 2.0, a composition library for .NET that enables dependency injection through attributes or conventions.
+
+This package provides core services for creating composition containers.
+It offers tools to configure and manage the composition of parts within your application, facilitating dependency injection and enabling modular architectures.
+
+## Key Features
+
+<!-- The key features of this package -->
+
+* Create and manage composition containers for dynamic dependency injection.
+
+## How to Use
+
+<!-- A compelling example on how to use this package with code, as well as any specific guidelines for when to use the package -->
+
+Create a composition host and compose parts.
+
+```csharp
+using System.Composition;
+using System.Composition.Hosting;
+
+// Create a container configuration
+var configuration = new ContainerConfiguration()
+    .WithPart<Service>();
+
+// Create the composition host (container)
+using CompositionHost container = configuration.CreateContainer();
+
+// Get an instance of the service
+var service = container.GetExport<IService>();
+service.Run();
+// Service is running!
+
+public interface IService
+{
+    void Run();
+}
+
+[Export(typeof(IService))]
+public class Service : IService
+{
+    public void Run() => Console.WriteLine("Service is running!");
+}
+```
+
+## Main Types
+
+<!-- The main types provided in this library -->
+
+The main type provided by this library is:
+
+* `System.Composition.CompositionHost`
+
+## Additional Documentation
+
+<!-- Links to further documentation. Remove conceptual documentation if not available for the library. -->
+
+* [API documentation](https://learn.microsoft.com/dotnet/api/system.composition.hosting)
+* [Managed Extensibility Framework (MEF)](https://learn.microsoft.com/dotnet/framework/mef/)
+
+## Related Packages
+
+<!-- The related packages associated with this package -->
+
+* [System.Composition](https://www.nuget.org/packages/System.Composition)
+* [System.Composition.AttributedModel](https://www.nuget.org/packages/System.Composition.AttributedModel)
+* [System.Composition.Convention](https://www.nuget.org/packages/System.Composition.Convention)
+* [System.Composition.Runtime](https://www.nuget.org/packages/System.Composition.Runtime)
+* [System.Composition.TypedParts](https://www.nuget.org/packages/System.Composition.TypedParts)
+
+## Feedback & Contributing
+
+<!-- How to provide feedback on this package and contribute to it -->
+
+System.Composition.Hosting is released as open source under the [MIT license](https://licenses.nuget.org/MIT).
+Bug reports and contributions are welcome at [the GitHub repository](https://github.com/dotnet/runtime).
diff --git a/src/libraries/System.Composition.Hosting/src/System.Composition.Hosting.csproj b/src/libraries/System.Composition.Hosting/src/System.Composition.Hosting.csproj
index cd017f48b6939..18d027e8ad14b 100644
--- a/src/libraries/System.Composition.Hosting/src/System.Composition.Hosting.csproj
+++ b/src/libraries/System.Composition.Hosting/src/System.Composition.Hosting.csproj
@@ -7,15 +7,10 @@
     <StrongNameKeyId>Microsoft</StrongNameKeyId>
     <UseCompilerGeneratedDocXmlFile>false</UseCompilerGeneratedDocXmlFile>
     <IsPackable>true</IsPackable>
-    <PackageDescription>Provides Managed Extensibility Framework types that are useful to developers of extensible applications, or hosts.
-
-Commonly Used Types:
-System.Composition.Hosting.CompositionHost</PackageDescription>
+    <PackageDescription>Provides Managed Extensibility Framework (MEF) types that are useful to developers of extensible applications, or hosts.</PackageDescription>
     <!-- TODO https://github.com/dotnet/runtime/issues/90400: Annotate for nullable reference types -->
     <Nullable>disable</Nullable>
     <NoWarn>$(NoWarn);nullable</NoWarn>
-    <!-- TODO: Add package README file: https://github.com/dotnet/runtime/issues/99358 -->
-    <EnableDefaultPackageReadmeFile>false</EnableDefaultPackageReadmeFile>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/src/libraries/System.Composition.Runtime/src/PACKAGE.md b/src/libraries/System.Composition.Runtime/src/PACKAGE.md
new file mode 100644
index 0000000000000..177bb8026881e
--- /dev/null
+++ b/src/libraries/System.Composition.Runtime/src/PACKAGE.md
@@ -0,0 +1,87 @@
+## About
+
+<!-- A description of the package and where one can find more documentation -->
+
+`System.Composition.Runtime` is part of the Managed Extensibility Framework (MEF) 2.0, a composition library for .NET that enables dependency injection through attributes or conventions.
+
+This package enables the discovery and composition of parts in applications using MEF 2.0.
+It offers the runtime implementation needed for managing composable parts, resolving dependencies, and dynamically wiring components together.
+
+## Key Features
+
+<!-- The key features of this package -->
+
+* Facilitates runtime discovery and composition of parts.
+
+## How to Use
+
+<!-- A compelling example on how to use this package with code, as well as any specific guidelines for when to use the package -->
+
+Resolve dependencies on the fly and can be useful for dynamically loaded components or plugins.
+
+```csharp
+using System.Composition;
+using System.Composition.Hosting;
+
+var configuration = new ContainerConfiguration()
+    .WithPart<Service>();
+
+using CompositionHost container = configuration.CreateContainer();
+ 
+var consumer = new Consumer(container);
+consumer.Execute();
+// Service is running.
+
+public interface IService
+{
+    void Run();
+}
+
+[Export(typeof(IService))]
+public class Service : IService
+{
+    public void Run() => Console.WriteLine("Service is running.");
+}
+
+public class Consumer(CompositionContext context)
+{
+    public void Execute()
+    {
+        // Use the context to resolve the service
+        var service = context.GetExport<IService>();
+        service.Run();
+    }
+}
+```
+
+## Main Types
+
+<!-- The main types provided in this library -->
+
+The main type provided by this library is:
+
+* `System.Composition.CompositionContext`
+
+## Additional Documentation
+
+<!-- Links to further documentation. Remove conceptual documentation if not available for the library. -->
+
+* [API documentation](https://learn.microsoft.com/dotnet/api/system.composition.compositioncontext)
+* [Managed Extensibility Framework (MEF)](https://learn.microsoft.com/dotnet/framework/mef/)
+
+## Related Packages
+
+<!-- The related packages associated with this package -->
+
+* [System.Composition](https://www.nuget.org/packages/System.Composition)
+* [System.Composition.AttributedModel](https://www.nuget.org/packages/System.Composition.AttributedModel)
+* [System.Composition.Convention](https://www.nuget.org/packages/System.Composition.Convention)
+* [System.Composition.Hosting](https://www.nuget.org/packages/System.Composition.Hosting)
+* [System.Composition.TypedParts](https://www.nuget.org/packages/System.Composition.TypedParts)
+
+## Feedback & Contributing
+
+<!-- How to provide feedback on this package and contribute to it -->
+
+System.Composition.Runtime is released as open source under the [MIT license](https://licenses.nuget.org/MIT).
+Bug reports and contributions are welcome at [the GitHub repository](https://github.com/dotnet/runtime).
diff --git a/src/libraries/System.Composition.Runtime/src/System.Composition.Runtime.csproj b/src/libraries/System.Composition.Runtime/src/System.Composition.Runtime.csproj
index 57ee9457ea35b..93ef06e572afe 100644
--- a/src/libraries/System.Composition.Runtime/src/System.Composition.Runtime.csproj
+++ b/src/libraries/System.Composition.Runtime/src/System.Composition.Runtime.csproj
@@ -7,15 +7,10 @@
     <StrongNameKeyId>Microsoft</StrongNameKeyId>
     <UseCompilerGeneratedDocXmlFile>false</UseCompilerGeneratedDocXmlFile>
     <IsPackable>true</IsPackable>
-    <PackageDescription>Contains runtime components of the Managed Extensibility Framework.
-
-Commonly Used Types:
-System.Composition.CompositionContext</PackageDescription>
+    <PackageDescription>Contains runtime components of the Managed Extensibility Framework (MEF).</PackageDescription>
     <!-- TODO https://github.com/dotnet/runtime/issues/90400: Annotate for nullable reference types -->
     <Nullable>disable</Nullable>
     <NoWarn>$(NoWarn);nullable</NoWarn>
-    <!-- TODO: Add package README file: https://github.com/dotnet/runtime/issues/99358 -->
-    <EnableDefaultPackageReadmeFile>false</EnableDefaultPackageReadmeFile>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/src/libraries/System.Composition.TypedParts/src/PACKAGE.md b/src/libraries/System.Composition.TypedParts/src/PACKAGE.md
new file mode 100644
index 0000000000000..de02f4525c866
--- /dev/null
+++ b/src/libraries/System.Composition.TypedParts/src/PACKAGE.md
@@ -0,0 +1,88 @@
+## About
+
+<!-- A description of the package and where one can find more documentation -->
+
+`System.Composition.TypedParts` is part of the Managed Extensibility Framework (MEF) 2.0, a composition library for .NET that enables dependency injection through attributes or conventions.
+
+Provides `ContainerConfiguration` and some extension methods for the Managed Extensibility Framework (MEF).
+
+## Key Features
+
+<!-- The key features of this package -->
+
+* Provides container configuration.
+
+## How to Use
+
+<!-- A compelling example on how to use this package with code, as well as any specific guidelines for when to use the package -->
+
+Register parts from an entire assembly.
+
+```csharp
+using System.Composition;
+using System.Composition.Hosting;
+using System.Reflection;
+
+// Register all parts from the current assembly
+var configuration = new ContainerConfiguration()
+    .WithAssembly(Assembly.GetExecutingAssembly());
+
+using CompositionHost container = configuration.CreateContainer();
+
+var handlers = container.GetExports<IHandler>();
+foreach (var handler in handlers)
+{
+    handler.Handle();
+}
+// HandlerA is handling.
+// HandlerB is handling.
+
+public interface IHandler
+{
+    void Handle();
+}
+
+[Export(typeof(IHandler))]
+public class HandlerA : IHandler
+{
+    public void Handle() => Console.WriteLine("HandlerA is handling.");
+}
+
+[Export(typeof(IHandler))]
+public class HandlerB : IHandler
+{
+    public void Handle() => Console.WriteLine("HandlerB is handling.");
+}
+```
+
+## Main Types
+
+<!-- The main types provided in this library -->
+
+The main types provided by this library are:
+
+* `System.Composition.Hosting.ContainerConfiguration`
+* `System.Composition.CompositionContextExtensions`
+
+## Additional Documentation
+
+<!-- Links to further documentation. Remove conceptual documentation if not available for the library. -->
+
+* [Managed Extensibility Framework (MEF)](https://learn.microsoft.com/dotnet/framework/mef/)
+
+## Related Packages
+
+<!-- The related packages associated with this package -->
+
+* [System.Composition](https://www.nuget.org/packages/System.Composition)
+* [System.Composition.AttributedModel](https://www.nuget.org/packages/System.Composition.AttributedModel)
+* [System.Composition.Convention](https://www.nuget.org/packages/System.Composition.Convention)
+* [System.Composition.Hosting](https://www.nuget.org/packages/System.Composition.Hosting)
+* [System.Composition.Runtime](https://www.nuget.org/packages/System.Composition.Runtime)
+
+## Feedback & Contributing
+
+<!-- How to provide feedback on this package and contribute to it -->
+
+System.Composition.TypedParts is released as open source under the [MIT license](https://licenses.nuget.org/MIT).
+Bug reports and contributions are welcome at [the GitHub repository](https://github.com/dotnet/runtime).
diff --git a/src/libraries/System.Composition.TypedParts/src/System.Composition.TypedParts.csproj b/src/libraries/System.Composition.TypedParts/src/System.Composition.TypedParts.csproj
index 4e82792a39994..3a2874d9d3f0b 100644
--- a/src/libraries/System.Composition.TypedParts/src/System.Composition.TypedParts.csproj
+++ b/src/libraries/System.Composition.TypedParts/src/System.Composition.TypedParts.csproj
@@ -8,16 +8,10 @@
     <StrongNameKeyId>Microsoft</StrongNameKeyId>
     <UseCompilerGeneratedDocXmlFile>false</UseCompilerGeneratedDocXmlFile>
     <IsPackable>true</IsPackable>
-    <PackageDescription>Provides some extension methods for the Managed Extensibility Framework.
-
-Commonly Used Types:
-System.Composition.CompositionContextExtensions
-System.Composition.Hosting.ContainerConfiguration</PackageDescription>
+    <PackageDescription>Provides container configuration and some extension methods for the Managed Extensibility Framework (MEF).</PackageDescription>
     <!-- TODO https://github.com/dotnet/runtime/issues/90400: Annotate for nullable reference types -->
     <Nullable>disable</Nullable>
     <NoWarn>$(NoWarn);nullable</NoWarn>
-    <!-- TODO: Add package README file: https://github.com/dotnet/runtime/issues/99358 -->
-    <EnableDefaultPackageReadmeFile>false</EnableDefaultPackageReadmeFile>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/src/libraries/System.Composition/src/PACKAGE.md b/src/libraries/System.Composition/src/PACKAGE.md
new file mode 100644
index 0000000000000..d6378b7ed0d56
--- /dev/null
+++ b/src/libraries/System.Composition/src/PACKAGE.md
@@ -0,0 +1,77 @@
+## About
+
+<!-- A description of the package and where one can find more documentation -->
+
+Provides the Managed Extensibility Framework (MEF) 2.0, a lightweight, attribute-driven Dependency Injection (DI) container.
+
+MEF simplifies the composition of applications by allowing components to be loosely coupled and dynamically discovered.
+This package supports the development of modular and maintainable applications by enabling parts to be composed at runtime.
+
+## Key Features
+
+<!-- The key features of this package -->
+
+* Components are discovered and composed using attributes.
+* Provides dependency injection capabilities for loosely coupled modules.
+
+## How to Use
+
+<!-- A compelling example on how to use this package with code, as well as any specific guidelines for when to use the package -->
+
+Running code from a discovered component.
+
+```csharp
+using System.Composition;
+using System.Composition.Hosting;
+
+var configuration = new ContainerConfiguration().WithPart<Service>();
+
+using var container = configuration.CreateContainer();
+
+var service = container.GetExport<Service>();
+service.Execute();
+// Output: Service is running!
+
+[Export]
+public class Service
+{
+    public void Execute() => Console.WriteLine("Service is running!");
+}
+```
+
+## Main Types
+
+<!-- The main types provided in this library -->
+
+The main types provided by this library are:
+
+* `System.Composition.ExportAttribute`
+* `System.Composition.ImportAttribute`
+* `System.Composition.Convention.ConventionBuilder`
+* `System.Composition.Hosting.CompositionHost`
+* `System.Composition.CompositionContext`
+* `System.Composition.CompositionContextExtensions`
+
+## Additional Documentation
+
+<!-- Links to further documentation. Remove conceptual documentation if not available for the library. -->
+
+* [API documentation](https://learn.microsoft.com/dotnet/api/system.composition)
+* [Managed Extensibility Framework (MEF)](https://learn.microsoft.com/dotnet/framework/mef/)
+
+## Related Packages
+
+<!-- The related packages associated with this package -->
+
+* [System.Composition.AttributedModel](https://www.nuget.org/packages/System.Composition.AttributedModel)
+* [System.Composition.Convention](https://www.nuget.org/packages/System.Composition.Convention)
+* [System.Composition.Hosting](https://www.nuget.org/packages/System.Composition.Hosting)
+* [System.Composition.Runtime](https://www.nuget.org/packages/System.Composition.Runtime)
+* [System.Composition.TypedParts](https://www.nuget.org/packages/System.Composition.TypedParts)
+
+## Feedback & Contributing
+
+<!-- How to provide feedback on this package and contribute to it -->
+
+System.Composition is released as open source under the [MIT license](https://licenses.nuget.org/MIT).
+Bug reports and contributions are welcome at [the GitHub repository](https://github.com/dotnet/runtime).
diff --git a/src/libraries/System.Composition/src/System.Composition.csproj b/src/libraries/System.Composition/src/System.Composition.csproj
index 0d0c67320ef72..a360f80b58e2b 100644
--- a/src/libraries/System.Composition/src/System.Composition.csproj
+++ b/src/libraries/System.Composition/src/System.Composition.csproj
@@ -8,21 +8,10 @@
     <NoWarn>$(NoWarn);NU5128</NoWarn>
     <!-- Reference dependencies to persiste them in the project's project.assets.json file which is used to calculate package dependencies. -->
     <NoTargetsDoNotReferenceOutputAssemblies>false</NoTargetsDoNotReferenceOutputAssemblies>
-    <PackageDescription>This package provides a version of the Managed Extensibility Framework (MEF) that is lightweight and specifically optimized for high throughput scenarios, such as the web.
-
-Commonly Used Types:
-System.Composition.ExportAttribute
-System.Composition.ImportAttribute
-System.Composition.Convention.ConventionBuilder
-System.Composition.Hosting.CompositionHost
-System.Composition.CompositionContext
-System.Composition.CompositionContextExtensions</PackageDescription>
-
+    <PackageDescription>Provides a version of the Managed Extensibility Framework (MEF) that is lightweight and specifically optimized for high throughput scenarios, such as the web.</PackageDescription>
     <!-- TODO https://github.com/dotnet/runtime/issues/90400: Annotate for nullable reference types -->
     <Nullable>disable</Nullable>
     <NoWarn>$(NoWarn);nullable</NoWarn>
-    <!-- TODO: Add package README file: https://github.com/dotnet/runtime/issues/99358 -->
-    <EnableDefaultPackageReadmeFile>false</EnableDefaultPackageReadmeFile>
   </PropertyGroup>
 
   <ItemGroup>