Revert "Add custom JSON mode generation option for Gemini language model (#80)" (#83)

This reverts commit f171982.

Author: mattt

Sources/AnyLanguageModel/Models/GeminiLanguageModel.swift

@@ -88,47 +88,17 @@ public struct GeminiLanguageModel: LanguageModel {
         /// (URL context), code execution, and location services (Google Maps).
         public var serverTools: [ServerTool]?
 
-        /// Configures JSON mode for structured output.
-        ///
-        /// Use this type to enable JSON mode,
-        /// which constrains the model to output a valid JSON.
-        /// Optionally provide a schema for typed JSON output.
-        public enum JSONMode: Sendable, Hashable, ExpressibleByBooleanLiteral {
-            /// JSON mode is disabled (default text output).
-            case disabled
-
-            /// JSON mode is enabled without a schema constraint.
-            case enabled
-
-            /// JSON mode is enabled with a schema constraint for typed output.
-            case schema(JSONSchema)
-
-            public init(booleanLiteral value: Bool) {
-                self = value ? .enabled : .disabled
-            }
-        }
-
-        /// The JSON mode configuration for structured output.
-        ///
-        /// When set to `.enabled`, the model will output valid JSON.
-        /// When set to `.schema(_:)`, the model will output JSON
-        /// conforming to the provided schema.
-        public var jsonMode: JSONMode?
-
         /// Creates custom generation options for Gemini models.
         ///
         /// - Parameters:
         ///   - thinking: The thinking mode configuration. When `nil`, uses the model's default.
         ///   - serverTools: Server-side tools to enable. When `nil`, uses the model's default.
-        ///   - jsonMode: The JSON mode configuration. When `nil`, uses the model's default.
         public init(
             thinking: Thinking? = nil,
-            serverTools: [ServerTool]? = nil,
-            jsonMode: JSONMode? = nil
+            serverTools: [ServerTool]? = nil
         ) {
             self.thinking = thinking
             self.serverTools = serverTools
-            self.jsonMode = jsonMode
         }
     }
 
@@ -270,7 +240,6 @@ public struct GeminiLanguageModel: LanguageModel {
         let customOptions = options[custom: GeminiLanguageModel.self]
         let effectiveThinking = customOptions?.thinking ?? _thinking
         let effectiveServerTools = customOptions?.serverTools ?? _serverTools
-        let effectiveJsonMode = customOptions?.jsonMode
 
         let url =
             baseURL
@@ -293,8 +262,7 @@ public struct GeminiLanguageModel: LanguageModel {
                 contents: contents,
                 tools: geminiTools,
                 options: options,
-                thinking: effectiveThinking,
-                jsonMode: effectiveJsonMode
+                thinking: effectiveThinking
             )
 
             let body = try JSONEncoder().encode(params)
@@ -382,7 +350,6 @@ public struct GeminiLanguageModel: LanguageModel {
         let customOptions = options[custom: GeminiLanguageModel.self]
         let effectiveThinking = customOptions?.thinking ?? _thinking
         let effectiveServerTools = customOptions?.serverTools ?? _serverTools
-        let effectiveJsonMode = customOptions?.jsonMode
 
         let userSegments = extractPromptSegments(from: session, fallbackText: prompt.description)
         let contents = [
@@ -408,8 +375,7 @@ public struct GeminiLanguageModel: LanguageModel {
                         contents: contents,
                         tools: geminiTools,
                         options: options,
-                        thinking: effectiveThinking,
-                        jsonMode: effectiveJsonMode
+                        thinking: effectiveThinking
                     )
 
                     let body = try JSONEncoder().encode(params)
@@ -494,8 +460,7 @@ private func createGenerateContentParams(
     contents: [GeminiContent],
     tools: [GeminiTool]?,
     options: GenerationOptions,
-    thinking: GeminiLanguageModel.CustomGenerationOptions.Thinking,
-    jsonMode: GeminiLanguageModel.CustomGenerationOptions.JSONMode?
+    thinking: GeminiLanguageModel.CustomGenerationOptions.Thinking
 ) throws -> [String: JSONValue] {
     var params: [String: JSONValue] = [
         "contents": try JSONValue(contents)
@@ -535,18 +500,6 @@ private func createGenerateContentParams(
     }
     generationConfig["thinkingConfig"] = .object(thinkingConfig)
 
-    if let jsonMode {
-        switch jsonMode {
-        case .disabled:
-            break
-        case .enabled:
-            generationConfig["responseMimeType"] = .string("application/json")
-        case .schema(let schema):
-            generationConfig["responseMimeType"] = .string("application/json")
-            generationConfig["responseSchema"] = try JSONValue(schema)
-        }
-    }
-
     if !generationConfig.isEmpty {
         params["generationConfig"] = .object(generationConfig)
     }

Tests/AnyLanguageModelTests/GeminiLanguageModelTests.swift

@@ -1,5 +1,4 @@
 import Foundation
-import JSONSchema
 import Testing
 
 @testable import AnyLanguageModel
@@ -145,46 +144,4 @@ struct GeminiLanguageModelTests {
         let response = try await session.respond(to: "")
         #expect(!response.content.isEmpty)
     }
-
-    @Test func jsonModeEnabled() async throws {
-        let session = LanguageModelSession(model: model)
-
-        var options = GenerationOptions()
-        options[custom: GeminiLanguageModel.self] = .init(
-            thinking: .disabled,
-            jsonMode: true
-        )
-
-        let response = try await session.respond(
-            to: "Return a JSON object with a 'greeting' key and value 'hello'",
-            options: options
-        )
-        #expect(response.content.contains("greeting"))
-        #expect(response.content.contains("hello"))
-    }
-
-    @Test func jsonModeWithSchema() async throws {
-        let session = LanguageModelSession(model: model)
-
-        let schema = JSONSchema.object(
-            properties: [
-                "name": .string(),
-                "age": .integer(),
-            ],
-            required: ["name", "age"]
-        )
-
-        var options = GenerationOptions()
-        options[custom: GeminiLanguageModel.self] = .init(
-            thinking: .disabled,
-            jsonMode: .schema(schema)
-        )
-
-        let response = try await session.respond(
-            to: "Generate a person with name 'Alice' and age 30",
-            options: options
-        )
-        #expect(response.content.contains("Alice"))
-        #expect(response.content.contains("30"))
-    }
 }