refactor: replace genAI model sdk by okHttp

agentscope-core/pom.xml

@@ -107,11 +107,6 @@
             </exclusions>
         </dependency>
 
-        <!-- Google Gemini Java SDK -->
-        <dependency>
-            <groupId>com.google.genai</groupId>
-            <artifactId>google-genai</artifactId>
-        </dependency>
 
         <!-- Anthropic Java SDK -->
         <dependency>

agentscope-core/src/main/java/io/agentscope/core/agent/AgentBase.java

@@ -26,6 +26,7 @@
 import io.agentscope.core.state.StateModule;
 import io.agentscope.core.tracing.TracerRegistry;
 import java.util.ArrayList;
+import java.util.Comparator;
 import java.util.List;
 import java.util.Map;
 import java.util.UUID;
@@ -479,7 +480,7 @@ protected void removeHook(Hook hook) {
      * @return Sorted list of hooks
      */
     protected List<Hook> getSortedHooks() {
-        return hooks.stream().sorted(java.util.Comparator.comparingInt(Hook::priority)).toList();
+        return hooks.stream().sorted(Comparator.comparingInt(Hook::priority)).toList();
     }
 
     /**

agentscope-core/src/main/java/io/agentscope/core/agent/accumulator/ToolCallsAccumulator.java

@@ -101,11 +101,26 @@ ToolUseBlock build() {
                 }
             }
 
+            // Build content string: prefer raw content, fall back to serialized args
+            String contentStr;
+            if (!rawContentStr.isEmpty()) {
+                contentStr = rawContentStr;
+            } else if (!finalArgs.isEmpty()) {
+                // Serialize the args map to JSON for validation
+                try {
+                    contentStr = JsonUtils.getJsonCodec().toJson(finalArgs);
+                } catch (Exception e) {
+                    contentStr = "{}";
+                }
+            } else {
+                contentStr = "{}";
+            }
+
             return ToolUseBlock.builder()
                     .id(toolId != null ? toolId : generateId())
                     .name(name)
                     .input(finalArgs)
-                    .content(rawContentStr.isEmpty() ? "{}" : rawContentStr)
+                    .content(contentStr)
                     .metadata(metadata.isEmpty() ? null : metadata)
                     .build();
         }

agentscope-core/src/main/java/io/agentscope/core/formatter/anthropic/AnthropicResponseParser.java

@@ -50,7 +50,7 @@ public static ChatResponse parseMessage(Message message, Instant startTime) {
         List<ContentBlock> contentBlocks = new ArrayList<>();
 
         // Process content blocks
-        for (com.anthropic.models.messages.ContentBlock block : message.content()) {
+        for (var block : message.content()) {
             // Text block
             block.text()
                     .ifPresent(

agentscope-core/src/main/java/io/agentscope/core/formatter/anthropic/AnthropicToolsHelper.java

@@ -15,6 +15,10 @@
  */
 package io.agentscope.core.formatter.anthropic;
 
+import static com.anthropic.models.messages.ToolChoice.ofAny;
+import static com.anthropic.models.messages.ToolChoice.ofAuto;
+import static com.anthropic.models.messages.ToolChoice.ofTool;
+
 import com.anthropic.core.JsonValue;
 import com.anthropic.core.ObjectMappers;
 import com.anthropic.models.messages.MessageCreateParams;
@@ -27,6 +31,7 @@
 import io.agentscope.core.model.ToolSchema;
 import java.util.List;
 import java.util.Map;
+import java.util.function.Function;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -86,27 +91,19 @@ private static JsonValue convertToJsonValue(Object parameters) {
     private static void applyToolChoice(
             MessageCreateParams.Builder builder, ToolChoice toolChoice) {
         if (toolChoice instanceof ToolChoice.Auto) {
-            builder.toolChoice(
-                    com.anthropic.models.messages.ToolChoice.ofAuto(
-                            ToolChoiceAuto.builder().build()));
+            builder.toolChoice(ofAuto(ToolChoiceAuto.builder().build()));
         } else if (toolChoice instanceof ToolChoice.None) {
             // Anthropic doesn't have None, use Any instead
-            builder.toolChoice(
-                    com.anthropic.models.messages.ToolChoice.ofAny(
-                            ToolChoiceAny.builder().build()));
+            builder.toolChoice(ofAny(ToolChoiceAny.builder().build()));
         } else if (toolChoice instanceof ToolChoice.Required) {
             // Anthropic doesn't have a direct "required" option, use "any" which forces tool
             // use
             log.warn(
                     "Anthropic API doesn't support ToolChoice.Required directly, using 'any'"
                             + " instead");
-            builder.toolChoice(
-                    com.anthropic.models.messages.ToolChoice.ofAny(
-                            ToolChoiceAny.builder().build()));
+            builder.toolChoice(ofAny(ToolChoiceAny.builder().build()));
         } else if (toolChoice instanceof ToolChoice.Specific specific) {
-            builder.toolChoice(
-                    com.anthropic.models.messages.ToolChoice.ofTool(
-                            ToolChoiceTool.builder().name(specific.toolName()).build()));
+            builder.toolChoice(ofTool(ToolChoiceTool.builder().name(specific.toolName()).build()));
         } else {
             log.warn("Unknown tool choice type: {}", toolChoice);
         }
@@ -203,7 +200,7 @@ private static void applyAdditionalQueryParams(
     private static <T> T getOption(
             GenerateOptions options,
             GenerateOptions defaultOptions,
-            java.util.function.Function<GenerateOptions, T> getter) {
+            Function<GenerateOptions, T> getter) {
         if (options != null) {
             T value = getter.apply(options);
             if (value != null) {