diff --git a/plugins/wasm-go/extensions/ai-proxy/provider/claude.go b/plugins/wasm-go/extensions/ai-proxy/provider/claude.go
index 79c2b321b..6db9b5d48 100644
--- a/plugins/wasm-go/extensions/ai-proxy/provider/claude.go
+++ b/plugins/wasm-go/extensions/ai-proxy/provider/claude.go
@@ -203,19 +203,20 @@ type claudeThinkingConfig struct {
 }
 
 type claudeTextGenRequest struct {
-	Model         string                `json:"model"`
-	Messages      []claudeChatMessage   `json:"messages"`
-	System        *claudeSystemPrompt   `json:"system,omitempty"`
-	MaxTokens     int                   `json:"max_tokens,omitempty"`
-	StopSequences []string              `json:"stop_sequences,omitempty"`
-	Stream        bool                  `json:"stream,omitempty"`
-	Temperature   float64               `json:"temperature,omitempty"`
-	TopP          float64               `json:"top_p,omitempty"`
-	TopK          int                   `json:"top_k,omitempty"`
-	ToolChoice    *claudeToolChoice     `json:"tool_choice,omitempty"`
-	Tools         []claudeTool          `json:"tools,omitempty"`
-	ServiceTier   string                `json:"service_tier,omitempty"`
-	Thinking      *claudeThinkingConfig `json:"thinking,omitempty"`
+	Model            string                `json:"model,omitempty"`
+	Messages         []claudeChatMessage   `json:"messages"`
+	System           *claudeSystemPrompt   `json:"system,omitempty"`
+	MaxTokens        int                   `json:"max_tokens,omitempty"`
+	StopSequences    []string              `json:"stop_sequences,omitempty"`
+	Stream           bool                  `json:"stream,omitempty"`
+	Temperature      float64               `json:"temperature,omitempty"`
+	TopP             float64               `json:"top_p,omitempty"`
+	TopK             int                   `json:"top_k,omitempty"`
+	ToolChoice       *claudeToolChoice     `json:"tool_choice,omitempty"`
+	Tools            []claudeTool          `json:"tools,omitempty"`
+	ServiceTier      string                `json:"service_tier,omitempty"`
+	Thinking         *claudeThinkingConfig `json:"thinking,omitempty"`
+	AnthropicVersion string                `json:"anthropic_version,omitempty"`
 }
 
 type claudeTextGenResponse struct {
diff --git a/plugins/wasm-go/extensions/ai-proxy/provider/vertex.go b/plugins/wasm-go/extensions/ai-proxy/provider/vertex.go
index fe15cc3ad..c66f5c44e 100644
--- a/plugins/wasm-go/extensions/ai-proxy/provider/vertex.go
+++ b/plugins/wasm-go/extensions/ai-proxy/provider/vertex.go
@@ -27,11 +27,16 @@ const (
 	vertexAuthDomain = "oauth2.googleapis.com"
 	vertexDomain     = "aiplatform.googleapis.com"
 	// /v1/projects/{PROJECT_ID}/locations/{REGION}/publishers/google/models/{MODEL_ID}:{ACTION}
-	vertexPathTemplate               = "/v1/projects/%s/locations/%s/publishers/google/models/%s:%s"
-	vertexChatCompletionAction       = "generateContent"
-	vertexChatCompletionStreamAction = "streamGenerateContent?alt=sse"
-	vertexEmbeddingAction            = "predict"
-	vertexGlobalRegion               = "global"
+	vertexPathTemplate                 = "/v1/projects/%s/locations/%s/publishers/google/models/%s:%s"
+	vertexPathAnthropicTemplate        = "/v1/projects/%s/locations/%s/publishers/anthropic/models/%s:%s"
+	vertexChatCompletionAction         = "generateContent"
+	vertexChatCompletionStreamAction   = "streamGenerateContent?alt=sse"
+	vertexAnthropicMessageAction       = "rawPredict"
+	vertexAnthropicMessageStreamAction = "streamRawPredict"
+	vertexEmbeddingAction              = "predict"
+	vertexGlobalRegion                 = "global"
+	contextClaudeMarker                = "isClaudeRequest"
+	vertexAnthropicVersion             = "vertex-2023-10-16"
 )
 
 type vertexProviderInitializer struct{}
@@ -66,6 +71,10 @@ func (v *vertexProviderInitializer) CreateProvider(config ProviderConfig) (Provi
 			Port:        443,
 		}),
 		contextCache: createContextCache(&config),
+		claude: &claudeProvider{
+			config:       config,
+			contextCache: createContextCache(&config),
+		},
 	}, nil
 }
 
@@ -73,6 +82,7 @@ type vertexProvider struct {
 	client       wrapper.HttpClient
 	config       ProviderConfig
 	contextCache *contextCache
+	claude       *claudeProvider
 }
 
 func (v *vertexProvider) GetProviderType() string {
@@ -145,6 +155,7 @@ func (v *vertexProvider) OnRequestBody(ctx wrapper.HttpContext, apiName ApiName,
 	}
 	headers := util.GetRequestHeaders()
 	body, err := v.TransformRequestBodyHeaders(ctx, apiName, body, headers)
+	headers.Set("Content-Length", fmt.Sprint(len(body)))
 	util.ReplaceRequestHeaders(headers)
 	_ = proxywasm.ReplaceHttpRequestBody(body)
 	if err != nil {
@@ -174,11 +185,26 @@ func (v *vertexProvider) onChatCompletionRequestBody(ctx wrapper.HttpContext, bo
 	if err != nil {
 		return nil, err
 	}
-	path := v.getRequestPath(ApiNameChatCompletion, request.Model, request.Stream)
-	util.OverwriteRequestPathHeader(headers, path)
+	if strings.HasPrefix(request.Model, "claude") {
+		ctx.SetContext(contextClaudeMarker, true)
+		path := v.getAhthropicRequestPath(ApiNameChatCompletion, request.Model, request.Stream)
+		util.OverwriteRequestPathHeader(headers, path)
 
-	vertexRequest := v.buildVertexChatRequest(request)
-	return json.Marshal(vertexRequest)
+		claudeRequest := v.claude.buildClaudeTextGenRequest(request)
+		claudeRequest.Model = ""
+		claudeRequest.AnthropicVersion = vertexAnthropicVersion
+		claudeBody, err := json.Marshal(claudeRequest)
+		if err != nil {
+			return nil, err
+		}
+		return claudeBody, nil
+	} else {
+		path := v.getRequestPath(ApiNameChatCompletion, request.Model, request.Stream)
+		util.OverwriteRequestPathHeader(headers, path)
+
+		vertexRequest := v.buildVertexChatRequest(request)
+		return json.Marshal(vertexRequest)
+	}
 }
 
 func (v *vertexProvider) onEmbeddingsRequestBody(ctx wrapper.HttpContext, body []byte, headers http.Header) ([]byte, error) {
@@ -194,6 +220,9 @@ func (v *vertexProvider) onEmbeddingsRequestBody(ctx wrapper.HttpContext, body [
 }
 
 func (v *vertexProvider) OnStreamingResponseBody(ctx wrapper.HttpContext, name ApiName, chunk []byte, isLastChunk bool) ([]byte, error) {
+	if ctx.GetContext(contextClaudeMarker) != nil && ctx.GetContext(contextClaudeMarker).(bool) {
+		return v.claude.OnStreamingResponseBody(ctx, name, chunk, isLastChunk)
+	}
 	log.Infof("[vertexProvider] receive chunk body: %s", string(chunk))
 	if isLastChunk {
 		return []byte(ssePrefix + "[DONE]\n\n"), nil
@@ -231,6 +260,9 @@ func (v *vertexProvider) OnStreamingResponseBody(ctx wrapper.HttpContext, name A
 }
 
 func (v *vertexProvider) TransformResponseBody(ctx wrapper.HttpContext, apiName ApiName, body []byte) ([]byte, error) {
+	if ctx.GetContext(contextClaudeMarker) != nil && ctx.GetContext(contextClaudeMarker).(bool) {
+		return v.claude.TransformResponseBody(ctx, apiName, body)
+	}
 	if apiName == ApiNameChatCompletion {
 		return v.onChatCompletionResponseBody(ctx, body)
 	} else {
@@ -326,6 +358,7 @@ func (v *vertexProvider) buildEmbeddingsResponse(ctx wrapper.HttpContext, vertex
 
 func (v *vertexProvider) buildChatCompletionStreamResponse(ctx wrapper.HttpContext, vertexResp *vertexChatResponse) *chatCompletionResponse {
 	var choice chatCompletionChoice
+	choice.Delta = &chatMessage{}
 	if len(vertexResp.Candidates) > 0 && len(vertexResp.Candidates[0].Content.Parts) > 0 {
 		part := vertexResp.Candidates[0].Content.Parts[0]
 		if part.FunctionCall != nil {
@@ -376,6 +409,16 @@ func (v *vertexProvider) appendResponse(responseBuilder *strings.Builder, respon
 	responseBuilder.WriteString(fmt.Sprintf("%s %s\n\n", streamDataItemKey, responseBody))
 }
 
+func (v *vertexProvider) getAhthropicRequestPath(apiName ApiName, modelId string, stream bool) string {
+	action := ""
+	if stream {
+		action = vertexAnthropicMessageStreamAction
+	} else {
+		action = vertexAnthropicMessageAction
+	}
+	return fmt.Sprintf(vertexPathAnthropicTemplate, v.config.vertexProjectId, v.config.vertexRegion, modelId, action)
+}
+
 func (v *vertexProvider) getRequestPath(apiName ApiName, modelId string, stream bool) string {
 	action := ""
 	if apiName == ApiNameEmbeddings {