chore(go): update samples and test cases

go/plugins/googlegenai/gemini.go

@@ -276,7 +276,10 @@ func generate(
 		if err != nil {
 			return nil, err
 		}
-		r := translateResponse(resp)
+		r, err := translateResponse(resp)
+		if err != nil {
+			return nil, err
+		}
 
 		r.Request = input
 		if cache != nil {
@@ -298,8 +301,11 @@ func generate(
 			return nil, err
 		}
 		for i, c := range chunk.Candidates {
-			tc := translateCandidate(c)
-			err := cb(ctx, &ai.ModelResponseChunk{
+			tc, err := translateCandidate(c)
+			if err != nil {
+				return nil, err
+			}
+			err = cb(ctx, &ai.ModelResponseChunk{
 				Content: tc.Message.Content,
 			})
 			if err != nil {
@@ -322,7 +328,10 @@ func generate(
 		},
 	}
 	resp.Candidates = merged
-	r = translateResponse(resp)
+	r, err = translateResponse(resp)
+	if err != nil {
+		return nil, fmt.Errorf("failed to generate contents: %w", err)
+	}
 	r.Request = input
 	if cache != nil {
 		r.Message.Metadata = cacheMetadata(r.Message.Metadata, cache)
@@ -339,11 +348,17 @@ func toGeminiRequest(input *ai.ModelRequest, cache *genai.CachedContent) (*genai
 		return nil, err
 	}
 
-	// only one candidate is supported by default
-	gcc.CandidateCount = 1
+	// candidate count might not be set to 1 and will keep its zero value if not set
+	// e.g. default value from reflection server is 0
+	if gcc.CandidateCount == 0 {
+		gcc.CandidateCount = 1
+	}
 
 	// Genkit primitive fields must be used instead of go-genai fields
 	// i.e.: system prompt, tools, cached content, response schema, etc
+	if gcc.CandidateCount != 1 {
+		return nil, errors.New("multiple candidates is not supported")
+	}
 	if gcc.SystemInstruction != nil {
 		return nil, errors.New("system instruction must be set using Genkit feature: ai.WithSystemPrompt()")
 	}
@@ -596,7 +611,7 @@ func toGeminiToolChoice(toolChoice ai.ToolChoice, tools []*ai.ToolDefinition) (*
 }
 
 // translateCandidate translates from a genai.GenerateContentResponse to an ai.ModelResponse.
-func translateCandidate(cand *genai.Candidate) *ai.ModelResponse {
+func translateCandidate(cand *genai.Candidate) (*ai.ModelResponse, error) {
 	m := &ai.ModelResponse{}
 	switch cand.FinishReason {
 	case genai.FinishReasonStop:
@@ -613,6 +628,10 @@ func translateCandidate(cand *genai.Candidate) *ai.ModelResponse {
 		m.FinishReason = ai.FinishReasonUnknown
 	}
 	msg := &ai.Message{}
+	if cand.Content == nil {
+		return nil, fmt.Errorf("no valid candidates were found in the generate response")
+	}
+
 	msg.Role = ai.Role(cand.Content.Role)
 
 	// iterate over the candidate parts, only one struct member
@@ -668,14 +687,19 @@ func translateCandidate(cand *genai.Candidate) *ai.ModelResponse {
 		msg.Content = append(msg.Content, p)
 	}
 	m.Message = msg
-	return m
+	return m, nil
 }
 
 // Translate from a genai.GenerateContentResponse to a ai.ModelResponse.
-func translateResponse(resp *genai.GenerateContentResponse) *ai.ModelResponse {
+func translateResponse(resp *genai.GenerateContentResponse) (*ai.ModelResponse, error) {
 	var r *ai.ModelResponse
+	var err error
 	if len(resp.Candidates) > 0 {
-		r = translateCandidate(resp.Candidates[0])
+		r, err = translateCandidate(resp.Candidates[0])
+		if err != nil {
+			return nil, err
+		}
+
 	} else {
 		r = &ai.ModelResponse{}
 	}
@@ -691,7 +715,7 @@ func translateResponse(resp *genai.GenerateContentResponse) *ai.ModelResponse {
 		r.Usage.CachedContentTokens = int(u.CachedContentTokenCount)
 		r.Usage.ThoughtsTokens = int(u.ThoughtsTokenCount)
 	}
-	return r
+	return r, nil
 }
 
 // toGeminiParts converts a slice of [ai.Part] to a slice of [genai.Part].

go/plugins/googlegenai/vertexai_live_test.go

@@ -36,16 +36,16 @@ func TestVertexAILive(t *testing.T) {
 	if !ok {
 		t.Skipf("GOOGLE_CLOUD_PROJECT env var not set")
 	}
-	location, ok := requireEnv("GOOGLE_CLOUD_LOCATION")
+	region, ok := requireEnv("GOOGLE_CLOUD_LOCATION")
 	if !ok {
 		t.Log("GOOGLE_CLOUD_LOCATION env var not set, defaulting to us-central1")
-		location = "us-central1"
+		region = "us-central1"
 	}
 
 	ctx := context.Background()
 	g := genkit.Init(ctx,
 		genkit.WithDefaultModel("vertexai/gemini-2.0-flash"),
-		genkit.WithPlugins(&googlegenai.VertexAI{ProjectID: projectID, Location: location}),
+		genkit.WithPlugins(&googlegenai.VertexAI{ProjectID: projectID, Location: region}),
 	)
 
 	embedder := googlegenai.VertexAIEmbedder(g, "textembedding-gecko@003")
@@ -264,8 +264,8 @@ func TestVertexAILive(t *testing.T) {
 		}
 	})
 	t.Run("image generation", func(t *testing.T) {
-		if location != "global" {
-			t.Skipf("image generation in Vertex AI is only supported in region: global, got: %s", location)
+		if region != "global" {
+			t.Skipf("image generation in Vertex AI is only supported in region: global, got: %s", region)
 		}
 		m := googlegenai.VertexAIModel(g, "gemini-2.0-flash-preview-image-generation")
 		resp, err := genkit.Generate(ctx, g,
@@ -328,8 +328,8 @@ func TestVertexAILive(t *testing.T) {
 		}
 	})
 	t.Run("thinking enabled", func(t *testing.T) {
-		if location != "global" && location != "us-central1" {
-			t.Skipf("thinking in Vertex AI is only supported in these regions: [global, us-central1], got: %q", location)
+		if region != "global" && region != "us-central1" {
+			t.Skipf("thinking in Vertex AI is only supported in these regions: [global, us-central1], got: %q", region)
 		}
 
 		m := googlegenai.VertexAIModel(g, "gemini-2.5-flash-preview-05-20")
@@ -360,8 +360,8 @@ func TestVertexAILive(t *testing.T) {
 		}
 	})
 	t.Run("thinking disabled", func(t *testing.T) {
-		if location != "global" && location != "us-central1" {
-			t.Skipf("thinking in Vertex AI is only supported in these regions: [global, us-central1], got: %q", location)
+		if region != "global" && region != "us-central1" {
+			t.Skipf("thinking in Vertex AI is only supported in these regions: [global, us-central1], got: %q", region)
 		}
 
 		m := googlegenai.VertexAIModel(g, "gemini-2.5-flash-preview-05-20")

go/plugins/ollama/ollama_live_test.go

@@ -26,16 +26,17 @@ import (
 	ollamaPlugin "github.com/firebase/genkit/go/plugins/ollama"
 )
 
-var serverAddress = flag.String("server-address", "http://localhost:11434", "Ollama server address")
-var modelName = flag.String("model-name", "tinyllama", "model name")
-var testLive = flag.Bool("test-live", false, "run live tests")
+var (
+	serverAddress = flag.String("server-address", "http://localhost:11434", "Ollama server address")
+	modelName     = flag.String("model-name", "tinyllama", "model name")
+	testLive      = flag.Bool("test-live", false, "run live tests")
+)
 
 /*
 To run this test, you need to have the Ollama server running. You can set the server address using the OLLAMA_SERVER_ADDRESS environment variable.
 If the environment variable is not set, the test will default to http://localhost:11434 (the default address for the Ollama server).
 */
 func TestLive(t *testing.T) {
-
 	if !*testLive {
 		t.Skip("skipping go/plugins/ollama live test")
 	}

go/plugins/vertexai/modelgarden/models.go

@@ -18,51 +18,113 @@ package modelgarden
 
 import (
 	"github.com/firebase/genkit/go/ai"
-	"github.com/firebase/genkit/go/plugins/internal"
 )
 
 const provider = "vertexai"
 
 // supported anthropic models
 var anthropicModels = map[string]ai.ModelOptions{
 	"claude-3-5-sonnet-v2": {
-		Label:    "Vertex AI Model Garden - Claude 3.5 Sonnet",
-		Supports: &internal.Multimodal,
+		Label: "Vertex AI Model Garden - Claude 3.5 Sonnet",
+		Supports: &ai.ModelSupports{
+			Multiturn:   true,
+			Tools:       true,
+			ToolChoice:  true,
+			SystemRole:  true,
+			Media:       true,
+			Constrained: ai.ConstrainedSupportNone,
+		},
 		Versions: []string{"claude-3-5-sonnet-v2@20241022"},
 	},
 	"claude-3-5-sonnet": {
-		Label:    "Vertex AI Model Garden - Claude 3.5 Sonnet",
-		Supports: &internal.Multimodal,
+		Label: "Vertex AI Model Garden - Claude 3.5 Sonnet",
+		Supports: &ai.ModelSupports{
+			Multiturn:   true,
+			Tools:       true,
+			ToolChoice:  true,
+			SystemRole:  true,
+			Media:       true,
+			Constrained: ai.ConstrainedSupportNone,
+		},
+
 		Versions: []string{"claude-3-5-sonnet@20240620"},
 	},
 	"claude-3-sonnet": {
-		Label:    "Vertex AI Model Garden - Claude 3 Sonnet",
-		Supports: &internal.Multimodal,
+		Label: "Vertex AI Model Garden - Claude 3 Sonnet",
+		Supports: &ai.ModelSupports{
+			Multiturn:   true,
+			Tools:       true,
+			ToolChoice:  true,
+			SystemRole:  true,
+			Media:       true,
+			Constrained: ai.ConstrainedSupportNone,
+		},
+
 		Versions: []string{"claude-3-sonnet@20240229"},
 	},
 	"claude-3-haiku": {
-		Label:    "Vertex AI Model Garden - Claude 3 Haiku",
-		Supports: &internal.Multimodal,
+		Label: "Vertex AI Model Garden - Claude 3 Haiku",
+		Supports: &ai.ModelSupports{
+			Multiturn:   true,
+			Tools:       true,
+			ToolChoice:  true,
+			SystemRole:  true,
+			Media:       true,
+			Constrained: ai.ConstrainedSupportNone,
+		},
+
 		Versions: []string{"claude-3-haiku@20240307"},
 	},
 	"claude-3-opus": {
-		Label:    "Vertex AI Model Garden - Claude 3 Opus",
-		Supports: &internal.Multimodal,
+		Label: "Vertex AI Model Garden - Claude 3 Opus",
+		Supports: &ai.ModelSupports{
+			Multiturn:   true,
+			Tools:       true,
+			ToolChoice:  true,
+			SystemRole:  true,
+			Media:       true,
+			Constrained: ai.ConstrainedSupportNone,
+		},
+
 		Versions: []string{"claude-3-opus@20240229"},
 	},
 	"claude-3-7-sonnet": {
-		Label:    "Vertex AI Model Garden - Claude 3.7 Sonnet",
-		Supports: &internal.Multimodal,
+		Label: "Vertex AI Model Garden - Claude 3.7 Sonnet",
+		Supports: &ai.ModelSupports{
+			Multiturn:   true,
+			Tools:       true,
+			ToolChoice:  true,
+			SystemRole:  true,
+			Media:       true,
+			Constrained: ai.ConstrainedSupportNone,
+		},
+
 		Versions: []string{"claude-3-7-sonnet@20250219"},
 	},
 	"claude-opus-4": {
-		Label:    "Vertex AI Model Garden - Claude Opus 4",
-		Supports: &internal.Multimodal,
+		Label: "Vertex AI Model Garden - Claude Opus 4",
+		Supports: &ai.ModelSupports{
+			Multiturn:   true,
+			Tools:       true,
+			ToolChoice:  true,
+			SystemRole:  true,
+			Media:       true,
+			Constrained: ai.ConstrainedSupportNone,
+		},
+
 		Versions: []string{"claude-opus-4@20250514"},
 	},
 	"claude-sonnet-4": {
-		Label:    "Vertex AI Model Garden - Claude Sonnet 4",
-		Supports: &internal.Multimodal,
+		Label: "Vertex AI Model Garden - Claude Sonnet 4",
+		Supports: &ai.ModelSupports{
+			Multiturn:   true,
+			Tools:       true,
+			ToolChoice:  true,
+			SystemRole:  true,
+			Media:       true,
+			Constrained: ai.ConstrainedSupportNone,
+		},
+
 		Versions: []string{"claude-sonnet-4@20250514"},
 	},
 }