feat: add Parallel AI Search tool support

examples/models/generate_content/parallel_ai_search.go

@@ -0,0 +1,72 @@
+// Copyright 2025 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build ignore_vet
+
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"log"
+
+	"google.golang.org/genai"
+)
+
+var model = flag.String("model", "gemini-2.5-flash", "the model name, e.g. gemini-2.5-flash")
+var parallelAPIKey = flag.String("parallel-api-key", "", "Parallel AI Search API key (required)")
+
+func run(ctx context.Context) {
+	client, err := genai.NewClient(ctx, nil)
+	if err != nil {
+		log.Fatal(err)
+	}
+	if client.ClientConfig().Backend != genai.BackendVertexAI {
+		log.Fatal("Parallel AI Search is only supported with Vertex AI backend")
+	}
+	fmt.Println("Calling VertexAI Backend...")
+
+	config := &genai.GenerateContentConfig{
+		Tools: []*genai.Tool{{
+			ParallelAiSearch: &genai.ParallelAiSearch{
+				APIKey: *parallelAPIKey,
+				CustomConfigs: &genai.ParallelAiSearchCustomConfigs{
+					MaxResults: genai.Ptr[int32](5),
+				},
+			},
+		}},
+	}
+
+	result, err := client.Models.GenerateContent(ctx, *model, genai.Text("What are the latest developments in AI?"), config)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Println("Response:", result.Text())
+	if len(result.Candidates) > 0 && result.Candidates[0].GroundingMetadata != nil {
+		jsonData, _ := json.MarshalIndent(result.Candidates[0].GroundingMetadata, "", "  ")
+		fmt.Println("Grounding metadata:", string(jsonData))
+	}
+}
+
+func main() {
+	ctx := context.Background()
+	flag.Parse()
+	if *parallelAPIKey == "" {
+		log.Fatal("--parallel-api-key is required")
+	}
+	run(ctx)
+}