diff --git a/.github/workflows/pull_request.yml b/.github/workflows/pull_request.yml
index d2df255..e178d7e 100644
--- a/.github/workflows/pull_request.yml
+++ b/.github/workflows/pull_request.yml
@@ -3,13 +3,19 @@ name: Build, tests & soundness checks
 on: [pull_request, workflow_dispatch]
 
 jobs:
-  swift-bedrock-library:
+  swift-bedrock-library-build:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
         uses: actions/checkout@v4
       - name: Build
         run: swift build --configuration release
+
+  swift-bedrock-library-test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
       - name: Tests
         run: swift test
 
diff --git a/Sources/Converse/ContentBlocks/DocumentToJSON.swift b/Sources/Converse/ContentBlocks/DocumentToJSON.swift
index a70ed84..d91ed5f 100644
--- a/Sources/Converse/ContentBlocks/DocumentToJSON.swift
+++ b/Sources/Converse/ContentBlocks/DocumentToJSON.swift
@@ -23,31 +23,34 @@ import Foundation
 
 // FIXME: avoid extensions on structs you do not control
 extension SmithyDocument {
-    public func toJSON() throws -> JSON {
+    private func toJSONValue() throws -> JSONValue {
         switch self.type {
         case .string:
-            return JSON(with: try self.asString())
+            return try JSONValue(self.asString())
         case .boolean:
-            return JSON(with: try self.asBoolean())
+            return try JSONValue(self.asBoolean())
         case .integer:
-            return JSON(with: try self.asInteger())
+            return try JSONValue(self.asInteger())
         case .double, .float:
-            return JSON(with: try self.asDouble())
+            return try JSONValue(self.asDouble())
         case .list:
-            let array = try self.asList().map { try $0.toJSON() }
-            return JSON(with: array)
+            let array = try self.asList().map { try $0.toJSONValue() }
+            return JSONValue(array)
         case .map:
             let map = try self.asStringMap()
-            var result: [String: JSON] = [:]
-            for (key, value) in map {
-                result[key] = try value.toJSON()
-            }
-            return JSON(with: result)
+            let newMap = try map.mapValues({ try $0.toJSONValue() })
+            return JSONValue(newMap)
         case .blob:
             let data = try self.asBlob()
-            return JSON(with: data)
+            let json = try JSON(from: data)
+            return json.value
         default:
             throw DocumentError.typeMismatch("Unsupported type for JSON conversion: \(self.type)")
         }
     }
+
+    public func toJSON() throws -> JSON {
+        let value = try self.toJSONValue()
+        return JSON(with: value)
+    }
 }
diff --git a/Sources/Converse/ContentBlocks/JSON.swift b/Sources/Converse/ContentBlocks/JSON.swift
index 5d17cc8..a6e76a6 100644
--- a/Sources/Converse/ContentBlocks/JSON.swift
+++ b/Sources/Converse/ContentBlocks/JSON.swift
@@ -19,57 +19,156 @@ import FoundationEssentials
 import Foundation
 #endif
 
-public struct JSON: Codable, @unchecked Sendable {  // FIXME: make Sendable
-    public var value: Any?
+public enum JSONValue: Codable, Sendable {
+    case null
+    case int(Int)
+    case double(Double)
+    case string(String)
+    case bool(Bool)
+    case array([JSONValue])
+    case object([String: JSONValue])
+
+    public init(_ value: Any?) {
+
+        guard let value else {
+            self = .null
+            return
+        }
+        switch value {
+        case let v as Int:
+            self = .int(v)
+            break
+        case let v as Double:
+            self = .double(v)
+            break
+        case let v as String:
+            self = .string(v)
+            break
+        case let v as Bool:
+            self = .bool(v)
+            break
+        case let v as [Any]:
+            self = .array(v.map { JSONValue($0) })
+            break
+        case let v as [String: JSONValue]:
+            self = .object(v)
+            break
+        case let v as [JSONValue]:
+            self = .array(v)
+            break
+        case let v as JSONValue:
+            self = v
+            break
+        default:
+            fatalError("JSONValue: Unsupported type: \(type(of: value))")
+        }
+    }
 
-    /// Returns the value inside the JSON object defined by the given key.
     public subscript<T>(key: String) -> T? {
         get {
-            if let dictionary = value as? [String: JSON] {
-                let json: JSON? = dictionary[key]
-                let nestedValue: Any? = json?.getValue()
-                return nestedValue as? T
+            if case let .object(dictionary) = self {
+                guard let jsonValue = dictionary[key] else {
+                    return nil
+                }
+                switch jsonValue {
+                case .int(let v): return v as? T
+                case .double(let v): return v as? T
+                case .string(let v): return v as? T
+                case .bool(let v): return v as? T
+                case .array(let v): return v as? T
+                case .object(let v): return v as? T
+                case .null: return nil
+                }
             }
             return nil
         }
     }
 
-    /// Returns the JSON object defined by the given key.
-    public subscript(key: String) -> JSON? {
+    public init(from decoder: Decoder) throws {
+        let container = try decoder.singleValueContainer()
+        if container.decodeNil() {
+            self = .null
+        } else if let intValue = try? container.decode(Int.self) {
+            self = .int(intValue)
+        } else if let doubleValue = try? container.decode(Double.self) {
+            self = .double(doubleValue)
+        } else if let stringValue = try? container.decode(String.self) {
+            self = .string(stringValue)
+        } else if let boolValue = try? container.decode(Bool.self) {
+            self = .bool(boolValue)
+        } else if let arrayValue = try? container.decode([JSONValue].self) {
+            self = .array(arrayValue)
+        } else if let dictionaryValue = try? container.decode([String: JSONValue].self) {
+            self = .object(dictionaryValue)
+        } else {
+            throw DecodingError.dataCorruptedError(in: container, debugDescription: "Unsupported type")
+        }
+    }
+
+    // MARK: Public Methods
+
+    public func encode(to encoder: Encoder) throws {
+        var container = encoder.singleValueContainer()
+        switch self {
+        case .null:
+            try container.encodeNil()
+        case .int(let v):
+            try container.encode(v)
+        case .double(let v):
+            try container.encode(v)
+        case .string(let v):
+            try container.encode(v)
+        case .bool(let v):
+            try container.encode(v)
+        case .array(let v):
+            try container.encode(v)
+        case .object(let v):
+            try container.encode(v)
+        }
+    }
+
+}
+
+public struct JSON: Codable, Sendable {
+    public let value: JSONValue
+
+    public subscript<T>(key: String) -> T? {
         get {
-            if let dictionary = value as? [String: JSON] {
-                return dictionary[key]
-            }
-            return nil
+            value[key]
         }
     }
 
-    /// Returns the value inside the JSON object defined by the given key.
-    public func getValue<T>(_ key: String) -> T? {
-        if let dictionary = value as? [String: JSON] {
-            return dictionary[key]?.value as? T
+    public subscript(key: String) -> JSONValue? {
+        get {
+            if case let .object(dictionary) = value {
+                if let v = dictionary[key] {
+                    return v
+                }
+            }
+            return nil
         }
-        return nil
     }
 
-    /// Returns the value inside the JSON object.
     public func getValue<T>() -> T? {
-        value as? T
+        switch value {
+        case .int(let v): return v as? T
+        case .double(let v): return v as? T
+        case .string(let v): return v as? T
+        case .bool(let v): return v as? T
+        case .array(let v): return v as? T
+        case .object(let v): return v as? T
+        case .null: return nil
+        }
     }
 
     // MARK: Initializers
 
-    public init(with value: Any?) {
+    public init(with value: JSONValue) {
         self.value = value
     }
 
     public init(from string: String) throws {
-        var s: String!
-        if string.isEmpty {
-            s = "{}"
-        } else {
-            s = string
-        }
+        let s = string.isEmpty ? "{}" : string
         guard let data = s.data(using: .utf8) else {
             throw BedrockLibraryError.encodingError("Could not encode String to Data")
         }
@@ -78,59 +177,18 @@ public struct JSON: Codable, @unchecked Sendable {  // FIXME: make Sendable
 
     public init(from data: Data) throws {
         do {
+            print(String(decoding: data, as: UTF8.self))
             self = try JSONDecoder().decode(JSON.self, from: data)
         } catch {
             throw BedrockLibraryError.decodingError("Failed to decode JSON: \(error)")
         }
     }
 
+    // Codable
+
     public init(from decoder: Decoder) throws {
         let container = try decoder.singleValueContainer()
-        if container.decodeNil() {
-            self.value = nil
-        } else if let intValue = try? container.decode(Int.self) {
-            self.value = intValue
-        } else if let doubleValue = try? container.decode(Double.self) {
-            self.value = doubleValue
-        } else if let stringValue = try? container.decode(String.self) {
-            self.value = stringValue
-        } else if let boolValue = try? container.decode(Bool.self) {
-            self.value = boolValue
-        } else if let arrayValue = try? container.decode([JSON].self) {
-            self.value = arrayValue.map { JSON(with: $0.value) }
-        } else if let dictionaryValue = try? container.decode([String: JSON].self) {
-            self.value = dictionaryValue.mapValues { JSON(with: $0.value) }
-        } else {
-            throw DecodingError.dataCorruptedError(in: container, debugDescription: "Unsupported type")
-        }
+        value = try container.decode(JSONValue.self)
     }
 
-    // MARK: Public Methods
-
-    public func encode(to encoder: Encoder) throws {
-        var container = encoder.singleValueContainer()
-        if let jsonValue = value as? JSON {
-            try jsonValue.encode(to: encoder)
-        } else if let intValue = value as? Int {
-            try container.encode(intValue)
-        } else if let doubleValue = value as? Double {
-            try container.encode(doubleValue)
-        } else if let stringValue = value as? String {
-            try container.encode(stringValue)
-        } else if let boolValue = value as? Bool {
-            try container.encode(boolValue)
-        } else if let arrayValue = value as? [Any] {
-            let jsonArray = arrayValue.map { JSON(with: $0) }
-            try container.encode(jsonArray)
-        } else if let dictionaryValue = value as? [String: Any] {
-            let jsonDictionary = dictionaryValue.mapValues { JSON(with: $0) }
-            try container.encode(jsonDictionary)
-        } else {
-            // try container.encode(String(describing: value ?? "nil"))
-            throw EncodingError.invalidValue(
-                value ?? "nil",
-                EncodingError.Context(codingPath: encoder.codingPath, debugDescription: "Unsupported type")
-            )
-        }
-    }
 }
diff --git a/Sources/Converse/ConverseRequest.swift b/Sources/Converse/ConverseRequest.swift
index 69f39c8..84879e6 100644
--- a/Sources/Converse/ConverseRequest.swift
+++ b/Sources/Converse/ConverseRequest.swift
@@ -70,13 +70,21 @@ public struct ConverseRequest {
     }
 
     func getAdditionalModelRequestFields() throws -> Smithy.Document? {
+        //FIXME: this is incorrect. We should check for all Claude models
         if model == .claudev3_7_sonnet, let maxReasoningTokens {
-            let reasoningConfigJSON = JSON(with: [
-                "thinking": [
-                    "type": "enabled",
-                    "budget_tokens": maxReasoningTokens,
-                ]
-            ])
+            let reasoningConfigJSON = JSON(
+                with: .array(
+                    [
+                        .object([
+                            "thinking": .object([
+                                "type": .string("enabled"),
+                                "budget_tokens": .int(maxReasoningTokens),
+                            ])
+                        ])
+                    ]
+                )
+            )
+
             return try reasoningConfigJSON.toDocument()
         }
         return nil
diff --git a/Tests/Converse/ConverseToolTests.swift b/Tests/Converse/ConverseToolTests.swift
index 9ff042c..68a0222 100644
--- a/Tests/Converse/ConverseToolTests.swift
+++ b/Tests/Converse/ConverseToolTests.swift
@@ -24,7 +24,7 @@ extension BedrockServiceTests {
     func converseRequestTool() async throws {
         let tool = try Tool(
             name: "toolName",
-            inputSchema: JSON(with: ["code": "string"]),
+            inputSchema: JSON(with: .object(["code": .string("string")])),
             description: "toolDescription"
         )
         let builder = try ConverseRequestBuilder(with: .nova_lite)
@@ -32,28 +32,25 @@ extension BedrockServiceTests {
             .withTool(tool)
         let reply = try await bedrock.converse(with: builder)
         #expect(reply.textReply == nil)
-        let id: String
-        let name: String
-        let input: JSON
+
         if let toolUse = reply.toolUse {
-            id = toolUse.id
-            name = toolUse.name
-            input = toolUse.input
+            #expect(toolUse.id == "toolId")
+            #expect(toolUse.name == "toolName")
+            #expect(toolUse.input["value"]?["code"] == "string")
         } else {
-            id = ""
-            name = ""
-            input = JSON(with: ["code": "wrong"])
+            Issue.record("Tool use is nil")
         }
-        #expect(id == "toolId")
-        #expect(name == "toolName")
-        #expect(input.getValue("code") == "abc")
     }
 
     @Test("Request tool usage with reused builder")
     func converseToolWithReusedBuilder() async throws {
         var builder = try ConverseRequestBuilder(with: .nova_lite)
             .withPrompt("Use tool")
-            .withTool(name: "toolName", inputSchema: JSON(with: ["code": "string"]), description: "toolDescription")
+            .withTool(
+                name: "toolName",
+                inputSchema: JSON(with: .object(["code": .string("string")])),
+                description: "toolDescription"
+            )
 
         #expect(builder.prompt != nil)
         #expect(builder.prompt! == "Use tool")
@@ -63,23 +60,15 @@ extension BedrockServiceTests {
 
         #expect(reply.textReply == nil)
 
-        let id: String
-        let name: String
-        let input: JSON
         if let toolUse = reply.toolUse {
-            id = toolUse.id
-            name = toolUse.name
-            input = toolUse.input
+            print(toolUse)
+            #expect(toolUse.id == "toolId")
+            #expect(toolUse.name == "toolName")
+            #expect(toolUse.input["value"]?["code"] == "string")
         } else {
-            id = ""
-            name = ""
-            input = JSON(with: ["code": "wrong"])
+            Issue.record("ToolUse is nil")
         }
 
-        #expect(id == "toolId")
-        #expect(name == "toolName")
-        #expect(input.getValue("code") == "abc")
-
         builder = try ConverseRequestBuilder(from: builder, with: reply)
             .withToolResult("Information from Tool")
 
@@ -109,7 +98,7 @@ extension BedrockServiceTests {
         #expect(throws: BedrockLibraryError.self) {
             let tool = try Tool(
                 name: "toolName",
-                inputSchema: JSON(with: ["code": "string"]),
+                inputSchema: JSON(with: .object(["code": .string("string")])),
                 description: "toolDescription"
             )
             let _ = try ConverseRequestBuilder(with: .titan_text_g1_express)
@@ -130,11 +119,11 @@ extension BedrockServiceTests {
     func converseToolResult() async throws {
         let tool = try Tool(
             name: "toolName",
-            inputSchema: JSON(with: ["code": "string"]),
+            inputSchema: JSON(with: .object(["code": .string("string")])),
             description: "toolDescription"
         )
         let id = "toolId"
-        let toolUse = ToolUseBlock(id: id, name: "toolName", input: JSON(with: ["code": "abc"]))
+        let toolUse = ToolUseBlock(id: id, name: "toolName", input: JSON(with: .object(["code": .string("string")])))
         let history = [Message("Use tool"), Message(toolUse)]
 
         let builder = try ConverseRequestBuilder(with: .nova_lite)
@@ -151,7 +140,7 @@ extension BedrockServiceTests {
     func converseToolResultWithoutToolUse() async throws {
         let tool = try Tool(
             name: "toolName",
-            inputSchema: JSON(with: ["code": "string"]),
+            inputSchema: JSON(with: .object(["code": .string("string")])),
             description: "toolDescription"
         )
         let id = "toolId"
@@ -167,7 +156,7 @@ extension BedrockServiceTests {
     @Test("Tool result without tools")
     func converseToolResultWithoutTools() async throws {
         let id = "toolId"
-        let toolUse = ToolUseBlock(id: id, name: "toolName", input: JSON(with: ["code": "abc"]))
+        let toolUse = ToolUseBlock(id: id, name: "toolName", input: JSON(with: .object(["code": .string("string")])))
         let history = [Message("Use tool"), Message(toolUse)]
         #expect(throws: BedrockLibraryError.self) {
             let _ = try ConverseRequestBuilder(with: .nova_lite)
@@ -180,11 +169,11 @@ extension BedrockServiceTests {
     func converseToolResultInvalidModel() async throws {
         let tool = try Tool(
             name: "toolName",
-            inputSchema: JSON(with: ["code": "string"]),
+            inputSchema: JSON(with: .object(["code": .string("string")])),
             description: "toolDescription"
         )
         let id = "toolId"
-        let toolUse = ToolUseBlock(id: id, name: "toolName", input: JSON(with: ["code": "abc"]))
+        let toolUse = ToolUseBlock(id: id, name: "toolName", input: JSON(with: .object(["code": .string("string")])))
         let history = [Message("Use tool"), Message(toolUse)]
         #expect(throws: BedrockLibraryError.self) {
             let _ = try ConverseRequestBuilder(with: .titan_text_g1_express)
@@ -197,7 +186,7 @@ extension BedrockServiceTests {
     @Test("Tool result with invalid model without tools")
     func converseToolResultInvalidModelWithoutTools() async throws {
         let id = "toolId"
-        let toolUse = ToolUseBlock(id: id, name: "toolName", input: JSON(with: ["code": "abc"]))
+        let toolUse = ToolUseBlock(id: id, name: "toolName", input: JSON(with: .object(["code": .string("abc")])))
         let history = [Message("Use tool"), Message(toolUse)]
 
         #expect(throws: BedrockLibraryError.self) {
@@ -211,7 +200,7 @@ extension BedrockServiceTests {
     func converseToolResultInvalidModelWithoutToolUse() async throws {
         let tool = try Tool(
             name: "toolName",
-            inputSchema: JSON(with: ["code": "string"]),
+            inputSchema: JSON(with: .object(["code": .string("string")])),
             description: "toolDescription"
         )
         let history = [Message("Use tool"), Message(from: .assistant, content: [.text("No need for a tool")])]
diff --git a/Tests/Converse/JSONTests.swift b/Tests/Converse/JSONTests.swift
index 409108a..707ac2f 100644
--- a/Tests/Converse/JSONTests.swift
+++ b/Tests/Converse/JSONTests.swift
@@ -21,98 +21,79 @@ import Testing
 @Suite("JSONTests")
 struct JSONTests {
 
-    @Test("JSON getValue")
-    func jsonGetValue() async throws {
-        let json = JSON(with: [
-            "name": JSON(with: "Jane Doe"),
-            "age": JSON(with: 30),
-            "isMember": JSON(with: true),
-        ])
-        #expect(json.getValue("name") == "Jane Doe")
-        #expect(json.getValue("age") == 30)
-        #expect(json.getValue("isMember") == true)
-        #expect(json.getValue("nonExistentKey") == nil)
+    @Test("JSON getValue from valid JSON string")
+    func jsonGetValueFromValidJSONString() async throws {
+
+        let json = try jsonFromString()
+        #expect(json["name"] == "Jane Doe")
+        #expect(json["age"] == 30)
+        #expect(json["isMember"] == true)
+        let t: String? = json["nonExistentKey"]
+        #expect(t == nil)
+    }
+
+    @Test("JSON getValue from [String:JSONValue]")
+    func jsonGetValueFromDictionary() async throws {
+        let json = try jsonFromDictionary()
+
+        #expect(json["name"] == "Jane Doe")
+        #expect(json["age"] == 30)
+        #expect(json["isMember"] == true)
+        let t: String? = json["nonExistentKey"]
+        #expect(t == nil)
     }
 
     @Test("JSON getValue nested")
     func jsonGetValueNested() async throws {
-        let json = JSON(with: [
-            "name": JSON(with: "Jane Doe"),
-            "age": JSON(with: 30),
-            "isMember": JSON(with: true),
-            "address": JSON(with: [
-                "street": JSON(with: "123 Main St"),
-                "city": JSON(with: "Anytown"),
-                "state": JSON(with: "CA"),
-                "zip": JSON(with: "12345"),
-                "isSomething": JSON(with: true),
-            ]),
-        ])
-        #expect(json.getValue("name") == "Jane Doe")
-        #expect(json.getValue("age") == 30)
-        #expect(json.getValue("isMember") == true)
-        #expect(json.getValue("nonExistentKey") == nil)
-        #expect(json["address"]?.getValue("street") == "123 Main St")
-        #expect(json["address"]?.getValue("city") == "Anytown")
-        #expect(json["address"]?.getValue("state") == "CA")
-        #expect(json["address"]?.getValue("zip") == "12345")
-        #expect(json["address"]?.getValue("isSomething") == true)
-        #expect(json["address"]?.getValue("nonExistentKey") == nil)
-    }
 
+        let json = try jsonFromDictionaryWithNested()
+        #expect(json["name"] == "Jane Doe")
+        #expect(json["age"] == 30)
+        #expect(json["isMember"] == true)
+        let t: String? = json["nonExistentKey"]
+        #expect(t == nil)
+        #expect(json["address"]?["street"] == "123 Main St")
+        #expect(json["address"]?["city"] == "Anytown")
+        #expect(json["address"]?["state"] == "CA")
+        #expect(json["address"]?["zip"] == 12345)
+        #expect(json["address"]?["isSomething"] == true)
+        let t2: String? = json["address"]?["nonExistentKey"]
+        #expect(t2 == nil)
+    }
+    //
     @Test("JSON Subscript")
     func jsonSubscript() async throws {
-        let json = JSON(with: [
-            "name": JSON(with: "Jane Doe"),
-            "age": JSON(with: 30),
-            "isMember": JSON(with: true),
-        ])
+        let json = try JSON(
+            from: """
+                {
+                    "name": "Jane Doe",
+                    "age": 30,
+                    "isMember": true
+                }
+                """
+        )
         #expect(json["name"] == "Jane Doe")
         #expect(json["age"] == 30)
         #expect(json["isMember"] == true)
-        #expect(json["nonExistentKey"] == nil)
+        let t: String? = json["nonExistentKey"]
+        #expect(t == nil)
     }
 
     @Test("JSON Subscript nested")
     func jsonSubscriptNested() async throws {
-        let json = JSON(with: [
-            "name": JSON(with: "Jane Doe"),
-            "age": JSON(with: 30),
-            "isMember": JSON(with: true),
-            "address": JSON(with: [
-                "street": JSON(with: "123 Main St"),
-                "city": JSON(with: "Anytown"),
-                "state": JSON(with: "CA"),
-                "zip": JSON(with: 12345),
-                "isSomething": JSON(with: true),
-            ]),
-        ])
+        let json = try jsonFromDictionaryWithNested()
         #expect(json["name"] == "Jane Doe")
         #expect(json["age"] == 30)
         #expect(json["isMember"] == true)
-        #expect(json["nonExistentKey"] == nil)
+        let t: String? = json["nonExistentKey"]
+        #expect(t == nil)
         #expect(json["address"]?["street"] == "123 Main St")
         #expect(json["address"]?["city"] == "Anytown")
         #expect(json["address"]?["state"] == "CA")
         #expect(json["address"]?["zip"] == 12345)
         #expect(json["address"]?["isSomething"] == true)
-        #expect(json["address"]?.getValue("nonExistentKey") == nil)
-    }
-
-    @Test("JSON String Initializer with Valid String")
-    func jsonStringInitializer() async throws {
-        let validJSONString = """
-            {
-                "name": "Jane Doe",
-                "age": 30,
-                "isMember": true
-            }
-            """
-
-        let json = try JSON(from: validJSONString)
-        #expect(json.getValue("name") == "Jane Doe")
-        #expect(json.getValue("age") == 30)
-        #expect(json.getValue("isMember") == true)
+        let t2: String? = json["address"]?["nonExistentKey"]
+        #expect(t2 == nil)
     }
 
     @Test("JSON String Initializer with Invalid String")
@@ -122,7 +103,8 @@ struct JSONTests {
                 "name": "Jane Doe",
                 "age": 30,
                 "isMember": true,
-            """  // Note: trailing comma, making this invalid
+
+            """  // Note: trailing comma and no closing brace, making this invalid
         #expect(throws: BedrockLibraryError.self) {
             let _ = try JSON(from: invalidJSONString)
         }
@@ -132,7 +114,56 @@ struct JSONTests {
     func emptyJSON() async throws {
         #expect(throws: Never.self) {
             let json = try JSON(from: "")
-            #expect(json.getValue("nonExistentKey") == nil)
+            let t: String? = json["nonExistentKey"]
+            #expect(t == nil)
         }
     }
+
+    @Test("Nested JSONValue")
+    func nestedJSONValue() {
+        JSON(
+            with: JSONValue([
+                "name": JSONValue("Jane Doe"),
+                "age": JSONValue(30),
+                "isMember": JSONValue(true),
+            ])
+        )
+
+    }
+}
+
+extension JSONTests {
+    private func jsonFromString() throws -> JSON {
+        try JSON(
+            from: """
+                {
+                    "name": "Jane Doe",
+                    "age": 30,
+                    "isMember": true
+                }
+                """
+        )
+    }
+
+    private func jsonFromDictionary() throws -> JSON {
+        let value: [String: JSONValue] = ["name": .string("Jane Doe"), "age": .int(30), "isMember": .bool(true)]
+        return JSON(with: .object(value))
+    }
+
+    private func jsonFromDictionaryWithNested() throws -> JSON {
+        JSON(
+            with: JSONValue([
+                "name": JSONValue("Jane Doe"),
+                "age": JSONValue(30),
+                "isMember": JSONValue(true),
+                "address": JSONValue([
+                    "street": JSONValue("123 Main St"),
+                    "city": JSONValue("Anytown"),
+                    "state": JSONValue("CA"),
+                    "zip": JSONValue(12345),
+                    "isSomething": JSONValue(true),
+                ]),
+            ])
+        )
+    }
 }
diff --git a/Tests/Converse/ToolResultBlockTests.swift b/Tests/Converse/ToolResultBlockTests.swift
index 927394a..797906e 100644
--- a/Tests/Converse/ToolResultBlockTests.swift
+++ b/Tests/Converse/ToolResultBlockTests.swift
@@ -39,15 +39,13 @@ extension BedrockServiceTests {
 
     @Test("ToolResultBlock Initializer with ID and JSON Content")
     func toolResultBlockInitializerWithJSON() async throws {
-        let json = JSON(with: ["key": JSON(with: "value")])
+        let json = JSON(with: .object(["key": .string("string")]))
         let block = ToolResultBlock(json, id: "block2")
         #expect(block.id == "block2")
         #expect(block.content.count == 1)
-        var value = ""
         if case .json(let json) = block.content.first {
-            value = json.getValue("key") ?? ""
+            #expect(json["key"] == "string")
         }
-        #expect(value == "value")
         #expect(block.status == .success)
     }
 
@@ -90,11 +88,9 @@ extension BedrockServiceTests {
 
         #expect(block.id == "block5")
         #expect(block.content.count == 1)
-        var value = ""
         if case .json(let json) = block.content.first {
-            value = json.getValue("key") ?? ""
+            #expect(json["key"] == "value")
         }
-        #expect(value == "value")
         #expect(block.status == block.status)
     }
 
@@ -108,14 +104,10 @@ extension BedrockServiceTests {
         let block = try ToolResultBlock(object, id: "block6")
         #expect(block.id == "block6")
         #expect(block.content.count == 1)
-        var name = ""
-        var age = 0
         if case .json(let jsonContent) = block.content.first {
-            name = jsonContent.getValue("name") ?? ""
-            age = jsonContent.getValue("age") ?? 0
+            #expect(jsonContent["name"] == "Jane")
+            #expect(jsonContent["age"] == 30)
         }
-        #expect(name == "Jane")
-        #expect(age == 30)
     }
 
     @Test("ToolResultBlock Initializer with Invalid Data Throws Error")
diff --git a/Tests/ConverseStream/ConverseStreamToolTests.swift b/Tests/ConverseStream/ConverseStreamToolTests.swift
index d02d2f9..1547417 100644
--- a/Tests/ConverseStream/ConverseStreamToolTests.swift
+++ b/Tests/ConverseStream/ConverseStreamToolTests.swift
@@ -24,7 +24,7 @@ extension ConverseReplyStreamTests {
     func converseStreamWithToolUse() async throws {
         let tool = try Tool(
             name: "toolName",
-            inputSchema: JSON(with: ["code": "string"]),
+            inputSchema: JSON(with: .object(["code": .string("string")])),
             description: "toolDescription"
         )
         var builder = try ConverseRequestBuilder(with: .nova_lite)
diff --git a/Tests/Mock/MockBedrockRuntimeClient.swift b/Tests/Mock/MockBedrockRuntimeClient.swift
index 844e1b8..764caf7 100644
--- a/Tests/Mock/MockBedrockRuntimeClient.swift
+++ b/Tests/Mock/MockBedrockRuntimeClient.swift
@@ -36,7 +36,7 @@ public struct MockBedrockRuntimeClient: BedrockRuntimeClientProtocol {
         var maxReasoningTokens: Int?
 
         if let additionalModelRequestFields = input.additionalModelRequestFields {
-            let json: JSON = JSON(with: additionalModelRequestFields)
+            let json = try additionalModelRequestFields.toJSON()
             reasoningEnabled = json["thinking"]?["enabled"]
             maxReasoningTokens = json["thinking"]?["budget_tokens"]
         }
@@ -117,7 +117,7 @@ public struct MockBedrockRuntimeClient: BedrockRuntimeClientProtocol {
         switch content {
         case .text(let prompt):
             if prompt == "Use tool", let _ = input.toolConfig?.tools {
-                let toolInputJson = JSON(with: ["code": "abc"])
+                let toolInputJson = JSON(with: .object(["code": .string("string")]))
                 let toolInput = try? toolInputJson.toDocument()
                 replyContent.append(
                     .tooluse(