diff --git a/clients/README.md b/clients/README.md
index b6964d2..f456603 100644
--- a/clients/README.md
+++ b/clients/README.md
@@ -6,7 +6,7 @@
 | `resolvespec-python` | Python >= 3.11 | ResolveSpec, HeaderSpec, FunctionSpec, WebSocketSpec | yes (61 tests) |
 | `resolvespec-go` | Go | ResolveSpec, FunctionSpec | yes (`go test`) |
 | `resolvespec-rs` | Rust | ResolveSpec, FunctionSpec | yes (`cargo test`) |
-| `resolvespec-cs` | C# (.NET 8) | ResolveSpec, FunctionSpec | **not compiled** |
+| `resolvespec-cs` | C# (.NET 8) | ResolveSpec, FunctionSpec | yes (`dotnet test`) |
 | `resolvespec-dart` | Dart / Flutter | ResolveSpec, FunctionSpec | yes (`dart test`) |
 
 Wire behaviour is identical across clients; FunctionSpec server quirks are listed in each README.
diff --git a/clients/resolvespec-cs/README.md b/clients/resolvespec-cs/README.md
index 41488e5..4853af8 100644
--- a/clients/resolvespec-cs/README.md
+++ b/clients/resolvespec-cs/README.md
@@ -2,7 +2,7 @@
 
 .NET 8 client for ResolveSpec (JSON body) and FunctionSpec. `System.Text.Json`, no other dependencies.
 
-> Not compiled or tested yet (no .NET SDK was available). Run `dotnet test tests/` first.
+> Tests run with `DOTNET_ROLL_FORWARD=Major` when only a newer runtime than 8.0 is installed.
 
 ## Clients
 
diff --git a/clients/resolvespec-cs/src/FuncSpecClient.cs b/clients/resolvespec-cs/src/FuncSpecClient.cs
index acdc588..84df0de 100644
--- a/clients/resolvespec-cs/src/FuncSpecClient.cs
+++ b/clients/resolvespec-cs/src/FuncSpecClient.cs
@@ -169,7 +169,9 @@ public sealed class FuncSpecClient
         };
         if (list)
         {
-            resp.Headers.TryGetValues("Content-Range", out var cr);
+            // Content-Range is a content header in HttpClient; fall back to response headers.
+            IEnumerable<string>? cr = null;
+            if (!resp.Content.Headers.TryGetValues("Content-Range", out cr)) resp.Headers.TryGetValues("Content-Range", out cr);
             r.Metadata = MetadataFrom(cr?.FirstOrDefault(), o);
         }
         return r;
diff --git a/clients/resolvespec-cs/src/ResolveSpecClient.cs b/clients/resolvespec-cs/src/ResolveSpecClient.cs
index c57e891..6b7bfb0 100644
--- a/clients/resolvespec-cs/src/ResolveSpecClient.cs
+++ b/clients/resolvespec-cs/src/ResolveSpecClient.cs
@@ -28,7 +28,7 @@ public sealed class ResolveSpecClient
         _ => Convert.ToString(id, System.Globalization.CultureInfo.InvariantCulture),
     };
 
-    static string[]? BodyId(object? id) => id is IEnumerable<string> e and not string ? e.ToArray() : null;
+    static string[]? BodyId(object? id) => id is IEnumerable<string> e ? e.ToArray() : null;
 
     string Url(string schema, string entity, string? id)
     {
diff --git a/clients/resolvespec-cs/tests/ClientTests.cs b/clients/resolvespec-cs/tests/ClientTests.cs
index 4a88311..075f7fc 100644
--- a/clients/resolvespec-cs/tests/ClientTests.cs
+++ b/clients/resolvespec-cs/tests/ClientTests.cs
@@ -22,7 +22,8 @@ public class Stub : HttpMessageHandler
         Request = request;
         Body = request.Content == null ? "" : await request.Content.ReadAsStringAsync(ct);
         var r = new HttpResponseMessage(_status) { Content = new StringContent(_json, Encoding.UTF8, "application/json") };
-        foreach (var (k, v) in _headers) r.Headers.TryAddWithoutValidation(k, v);
+        foreach (var (k, v) in _headers)
+            if (!r.Headers.TryAddWithoutValidation(k, v)) r.Content.Headers.TryAddWithoutValidation(k, v);
         return r;
     }
 }