```
These APIs were previously available via nuget and are now available in-box.
```
# System.Net.Http.Json

``` diff
+namespace System.Net.Http.Json {
+    public static class HttpClientJsonExtensions {
+        public static Task<object> GetFromJsonAsync(this HttpClient client, string requestUri, Type type, JsonSerializerOptions options, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<object> GetFromJsonAsync(this HttpClient client, string requestUri, Type type, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<object> GetFromJsonAsync(this HttpClient client, Uri requestUri, Type type, JsonSerializerOptions options, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<object> GetFromJsonAsync(this HttpClient client, Uri requestUri, Type type, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<TValue> GetFromJsonAsync<TValue>(this HttpClient client, string requestUri, JsonSerializerOptions options, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<TValue> GetFromJsonAsync<TValue>(this HttpClient client, string requestUri, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<TValue> GetFromJsonAsync<TValue>(this HttpClient client, Uri requestUri, JsonSerializerOptions options, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<TValue> GetFromJsonAsync<TValue>(this HttpClient client, Uri requestUri, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<HttpResponseMessage> PostAsJsonAsync<TValue>(this HttpClient client, string requestUri, TValue value, JsonSerializerOptions options = null, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<HttpResponseMessage> PostAsJsonAsync<TValue>(this HttpClient client, string requestUri, TValue value, CancellationToken cancellationToken);
+        public static Task<HttpResponseMessage> PostAsJsonAsync<TValue>(this HttpClient client, Uri requestUri, TValue value, JsonSerializerOptions options = null, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<HttpResponseMessage> PostAsJsonAsync<TValue>(this HttpClient client, Uri requestUri, TValue value, CancellationToken cancellationToken);
+        public static Task<HttpResponseMessage> PutAsJsonAsync<TValue>(this HttpClient client, string requestUri, TValue value, JsonSerializerOptions options = null, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<HttpResponseMessage> PutAsJsonAsync<TValue>(this HttpClient client, string requestUri, TValue value, CancellationToken cancellationToken);
+        public static Task<HttpResponseMessage> PutAsJsonAsync<TValue>(this HttpClient client, Uri requestUri, TValue value, JsonSerializerOptions options = null, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<HttpResponseMessage> PutAsJsonAsync<TValue>(this HttpClient client, Uri requestUri, TValue value, CancellationToken cancellationToken);
+    }
+    public static class HttpContentJsonExtensions {
+        public static Task<object> ReadFromJsonAsync(this HttpContent content, Type type, JsonSerializerOptions options = null, CancellationToken cancellationToken = default(CancellationToken));
+        public static Task<T> ReadFromJsonAsync<T>(this HttpContent content, JsonSerializerOptions options = null, CancellationToken cancellationToken = default(CancellationToken));
+    }
+    public sealed class JsonContent : HttpContent {
+        public Type ObjectType { get; }
+        public object Value { get; }
+        public static JsonContent Create(object inputValue, Type inputType, MediaTypeHeaderValue mediaType = null, JsonSerializerOptions options = null);
+        public static JsonContent Create<T>(T inputValue, MediaTypeHeaderValue mediaType = null, JsonSerializerOptions options = null);
+        protected override void SerializeToStream(Stream stream, TransportContext context, CancellationToken cancellationToken);
+        protected override Task SerializeToStreamAsync(Stream stream, TransportContext context);
+        protected override Task SerializeToStreamAsync(Stream stream, TransportContext context, CancellationToken cancellationToken);
+        protected override bool TryComputeLength(out long length);
+    }
+}
```

