diff --git a/tests/FSharp.Data.Core.Tests/FSharp.Data.Core.Tests.fsproj b/tests/FSharp.Data.Core.Tests/FSharp.Data.Core.Tests.fsproj
index dbbe3e5fd..ab66f9ed0 100644
--- a/tests/FSharp.Data.Core.Tests/FSharp.Data.Core.Tests.fsproj
+++ b/tests/FSharp.Data.Core.Tests/FSharp.Data.Core.Tests.fsproj
@@ -35,6 +35,7 @@
     <Compile Include="JsonDocument.fs" />
     <Compile Include="JsonRuntime.fs" />
     <Compile Include="JsonSchema.fs" />
+    <Compile Include="JsonValueOptionExtensions.fs" />
     <Compile Include="CsvReader.fs" />
     <Compile Include="CsvFile.fs" />
     <Compile Include="CsvRuntimeOperations.fs" />
diff --git a/tests/FSharp.Data.Core.Tests/JsonValueOptionExtensions.fs b/tests/FSharp.Data.Core.Tests/JsonValueOptionExtensions.fs
new file mode 100644
index 000000000..88363edba
--- /dev/null
+++ b/tests/FSharp.Data.Core.Tests/JsonValueOptionExtensions.fs
@@ -0,0 +1,170 @@
+module FSharp.Data.Tests.JsonValueInnerTextAndExtensions
+
+open NUnit.Framework
+open FsUnit
+open System
+open System.Globalization
+open FSharp.Data
+open FSharp.Data.JsonExtensions
+
+// ============================================================
+// JsonExtensions.InnerText — C# [<Extension>] method
+// Returns AsString result for scalar values; concatenates array elements
+// ============================================================
+
+[<Test>]
+let ``InnerText returns string content for a String value`` () =
+    JsonValue.String("hello world").InnerText() |> should equal "hello world"
+
+[<Test>]
+let ``InnerText returns empty string for Null`` () =
+    JsonValue.Null.InnerText() |> should equal ""
+
+[<Test>]
+let ``InnerText returns string representation for Boolean true`` () =
+    JsonValue.Boolean(true).InnerText() |> should equal "true"
+
+[<Test>]
+let ``InnerText returns string representation for Boolean false`` () =
+    JsonValue.Boolean(false).InnerText() |> should equal "false"
+
+[<Test>]
+let ``InnerText returns string representation for Number`` () =
+    JsonValue.Number(42M).InnerText() |> should equal "42"
+
+[<Test>]
+let ``InnerText returns string representation for Float`` () =
+    JsonValue.Float(3.14).InnerText() |> should startWith "3.14"
+
+[<Test>]
+let ``InnerText concatenates string elements of an array`` () =
+    let json = JsonValue.Parse """["foo","bar","baz"]"""
+    json.InnerText() |> should equal "foobarbaz"
+
+[<Test>]
+let ``InnerText returns empty string for an empty array`` () =
+    JsonValue.Array([||]).InnerText() |> should equal ""
+
+[<Test>]
+let ``InnerText includes numeric elements in a mixed array`` () =
+    let json = JsonValue.Parse """["hello", 42, "world"]"""
+    json.InnerText() |> should equal "hello42world"
+
+[<Test>]
+let ``InnerText returns empty string for a record object`` () =
+    let json = JsonValue.Parse """{"key":"value"}"""
+    json.InnerText() |> should equal ""
+
+[<Test>]
+let ``InnerText handles Unicode strings correctly`` () =
+    JsonValue.String("こんにちは").InnerText() |> should equal "こんにちは"
+
+[<Test>]
+let ``InnerText handles empty string`` () =
+    JsonValue.String("").InnerText() |> should equal ""
+
+[<Test>]
+let ``InnerText concatenates array of strings`` () =
+    let json = JsonValue.Parse """["a","b","c","d","e"]"""
+    json.InnerText() |> should equal "abcde"
+
+// ============================================================
+// JsonValue.Properties — F# augmentation member
+// ============================================================
+
+[<Test>]
+let ``Properties returns all key-value pairs for a Record`` () =
+    let json = JsonValue.Parse """{"x":1,"y":2,"z":3}"""
+    let props = json.Properties
+    props |> should haveLength 3
+    props |> Array.map fst |> should equal [| "x"; "y"; "z" |]
+
+[<Test>]
+let ``Properties returns empty array for an empty record`` () =
+    JsonValue.Record([||]).Properties |> should haveLength 0
+
+[<Test>]
+let ``Properties returns empty array for a non-record value`` () =
+    JsonValue.String("text").Properties |> should haveLength 0
+    JsonValue.Array([||]).Properties |> should haveLength 0
+    JsonValue.Null.Properties |> should haveLength 0
+    JsonValue.Boolean(false).Properties |> should haveLength 0
+
+// ============================================================
+// AsGuid — additional edge cases
+// ============================================================
+
+[<Test>]
+let ``AsGuid parses lowercase GUID string`` () =
+    let j = JsonValue.Parse """{"id":"550e8400-e29b-41d4-a716-446655440000"}"""
+    j?id.AsGuid() |> should equal (Guid.Parse "550e8400-e29b-41d4-a716-446655440000")
+
+[<Test>]
+let ``AsGuid parses uppercase GUID string`` () =
+    let j = JsonValue.Parse """{"id":"550E8400-E29B-41D4-A716-446655440000"}"""
+    j?id.AsGuid() |> should equal (Guid.Parse "550E8400-E29B-41D4-A716-446655440000")
+
+[<Test>]
+let ``AsGuid throws for invalid GUID string`` () =
+    let j = JsonValue.Parse """{"id":"not-a-guid"}"""
+    (fun () -> j?id.AsGuid() |> ignore) |> should throw typeof<Exception>
+
+// ============================================================
+// AsBoolean — string-to-bool conversion cases
+// ============================================================
+
+[<Test>]
+let ``AsBoolean parses true string`` () =
+    let j = JsonValue.Parse """{"flag":"true"}"""
+    j?flag.AsBoolean() |> should equal true
+
+[<Test>]
+let ``AsBoolean parses false string`` () =
+    let j = JsonValue.Parse """{"flag":"false"}"""
+    j?flag.AsBoolean() |> should equal false
+
+[<Test>]
+let ``AsBoolean parses yes/no strings`` () =
+    let j = JsonValue.Parse """{"a":"yes","b":"no"}"""
+    j?a.AsBoolean() |> should equal true
+    j?b.AsBoolean() |> should equal false
+
+[<Test>]
+let ``AsBoolean parses 1/0 strings`` () =
+    let j = JsonValue.Parse """{"a":"1","b":"0"}"""
+    j?a.AsBoolean() |> should equal true
+    j?b.AsBoolean() |> should equal false
+
+[<Test>]
+let ``AsBoolean throws for invalid boolean string`` () =
+    let j = JsonValue.Parse """{"flag":"maybe"}"""
+    (fun () -> j?flag.AsBoolean() |> ignore) |> should throw typeof<Exception>
+
+// ============================================================
+// AsTimeSpan — additional edge cases
+// ============================================================
+
+[<Test>]
+let ``AsTimeSpan throws for non-timespan value`` () =
+    let j = JsonValue.Parse """{"d":"not-a-timespan"}"""
+    (fun () -> j?d.AsTimeSpan() |> ignore) |> should throw typeof<Exception>
+
+[<Test>]
+let ``AsTimeSpan parses zero duration`` () =
+    // Uses .NET TimeSpan.Parse format: "0:00:00"
+    let j = JsonValue.Parse """{"d":"0:00:00"}"""
+    j?d.AsTimeSpan() |> should equal TimeSpan.Zero
+
+// ============================================================
+// Dynamic operator (?) edge cases
+// ============================================================
+
+[<Test>]
+let ``Dynamic operator accesses nested string property`` () =
+    let j = JsonValue.Parse """{"person":{"name":"Alice"}}"""
+    j?person?name.AsString() |> should equal "Alice"
+
+[<Test>]
+let ``Dynamic operator throws for missing property`` () =
+    let j = JsonValue.Parse """{"x":1}"""
+    (fun () -> j?missing |> ignore) |> should throw typeof<Exception>