diff --git a/.github/workflows/tests-e2e.yml b/.github/workflows/tests-e2e.yml
new file mode 100644
index 000000000..b7ba47feb
--- /dev/null
+++ b/.github/workflows/tests-e2e.yml
@@ -0,0 +1,56 @@
+---
+name: 'E2E Backend Tests'
+
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+    tags:
+      - '*'
+
+concurrency:
+  group: ci-tests-e2e-backend-${{ github.head_ref || github.ref }}-${{ github.repository }}
+  cancel-in-progress: true
+
+jobs:
+  tests-e2e-backend:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        go-version: ['1.25.x']
+    steps:
+      - name: Clone
+        uses: actions/checkout@v6
+        with:
+          submodules: true
+      - name: Setup Go ${{ matrix.go-version }}
+        uses: actions/setup-go@v5
+        with:
+          go-version: ${{ matrix.go-version }}
+          cache: false
+      - name: Display Go version
+        run: go version
+      - name: Proto Dependencies
+        run: |
+          # Install protoc
+          curl -L -s https://github.com/protocolbuffers/protobuf/releases/download/v26.1/protoc-26.1-linux-x86_64.zip -o protoc.zip && \
+          unzip -j -d /usr/local/bin protoc.zip bin/protoc && \
+          rm protoc.zip
+          go install google.golang.org/protobuf/cmd/protoc-gen-go@v1.34.2
+          go install google.golang.org/grpc/cmd/protoc-gen-go-grpc@1958fcbe2ca8bd93af633f11e97d44e567e945af
+          PATH="$PATH:$HOME/go/bin" make protogen-go
+      - name: Dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y build-essential
+      - name: Test Backend E2E
+        run: |
+          PATH="$PATH:$HOME/go/bin" make build-mock-backend test-e2e
+      - name: Setup tmate session if tests fail
+        if: ${{ failure() }}
+        uses: mxschmitt/action-tmate@v3.23
+        with:
+          detached: true
+          connect-timeout-seconds: 180
+          limit-access-to-actor: true
diff --git a/Makefile b/Makefile
index 7f4941532..505b4eba7 100644
--- a/Makefile
+++ b/Makefile
@@ -191,9 +191,6 @@ run-e2e-aio: protogen-go
 ########################################################
 
 prepare-e2e:
-	mkdir -p $(TEST_DIR)
-	cp -rfv $(abspath ./tests/e2e-fixtures)/gpu.yaml $(TEST_DIR)/gpu.yaml
-	test -e $(TEST_DIR)/ggllm-test-model.bin || wget -q https://huggingface.co/TheBloke/CodeLlama-7B-Instruct-GGUF/resolve/main/codellama-7b-instruct.Q2_K.gguf -O $(TEST_DIR)/ggllm-test-model.bin
 	docker build \
 		--build-arg IMAGE_TYPE=core \
 		--build-arg BUILD_TYPE=$(BUILD_TYPE) \
@@ -207,14 +204,16 @@ prepare-e2e:
 		-t localai-tests .
 
 run-e2e-image:
-	ls -liah $(abspath ./tests/e2e-fixtures)
-	docker run -p 5390:8080 -e MODELS_PATH=/models -e THREADS=1 -e DEBUG=true -d --rm -v $(TEST_DIR):/models --gpus all --name e2e-tests-$(RANDOM) localai-tests
+	docker run -p 5390:8080 -e MODELS_PATH=/models -e THREADS=1 -e DEBUG=true -d --rm -v $(TEST_DIR):/models --name e2e-tests-$(RANDOM) localai-tests
 
-test-e2e:
+test-e2e: build-mock-backend prepare-e2e run-e2e-image
 	@echo 'Running e2e tests'
 	BUILD_TYPE=$(BUILD_TYPE) \
-	LOCALAI_API=http://$(E2E_BRIDGE_IP):5390/v1 \
+	LOCALAI_API=http://$(E2E_BRIDGE_IP):5390 \
 	$(GOCMD) run github.com/onsi/ginkgo/v2/ginkgo --flake-attempts $(TEST_FLAKES) -v -r ./tests/e2e
+	$(MAKE) clean-mock-backend
+	$(MAKE) teardown-e2e
+	docker rmi localai-tests
 
 teardown-e2e:
 	rm -rf $(TEST_DIR) || true
@@ -522,6 +521,16 @@ docker-save-%: backend-images
 
 docker-build-backends: docker-build-llama-cpp docker-build-rerankers docker-build-vllm docker-build-vllm-omni docker-build-transformers docker-build-diffusers docker-build-kokoro docker-build-faster-whisper docker-build-coqui docker-build-chatterbox docker-build-vibevoice docker-build-moonshine docker-build-pocket-tts docker-build-qwen-tts docker-build-qwen-asr docker-build-voxcpm
 
+########################################################
+### Mock Backend for E2E Tests
+########################################################
+
+build-mock-backend: protogen-go
+	$(GOCMD) build -o tests/e2e/mock-backend/mock-backend ./tests/e2e/mock-backend
+
+clean-mock-backend:
+	rm -f tests/e2e/mock-backend/mock-backend
+
 ########################################################
 ### END Backends
 ########################################################
diff --git a/core/http/endpoints/anthropic/messages.go b/core/http/endpoints/anthropic/messages.go
index 389d60466..12d500125 100644
--- a/core/http/endpoints/anthropic/messages.go
+++ b/core/http/endpoints/anthropic/messages.go
@@ -88,21 +88,38 @@ func MessagesEndpoint(cl *config.ModelConfigLoader, ml *model.ModelLoader, evalu
 		xlog.Debug("Anthropic Messages - Prompt (after templating)", "prompt", predInput)
 
 		if input.Stream {
-			return handleAnthropicStream(c, id, input, cfg, ml, predInput, openAIReq, funcs, shouldUseFn)
+			return handleAnthropicStream(c, id, input, cfg, ml, cl, appConfig, predInput, openAIReq, funcs, shouldUseFn)
 		}
 
-		return handleAnthropicNonStream(c, id, input, cfg, ml, predInput, openAIReq, funcs, shouldUseFn)
+		return handleAnthropicNonStream(c, id, input, cfg, ml, cl, appConfig, predInput, openAIReq, funcs, shouldUseFn)
 	}
 }
 
-func handleAnthropicNonStream(c echo.Context, id string, input *schema.AnthropicRequest, cfg *config.ModelConfig, ml *model.ModelLoader, predInput string, openAIReq *schema.OpenAIRequest, funcs functions.Functions, shouldUseFn bool) error {
+func handleAnthropicNonStream(c echo.Context, id string, input *schema.AnthropicRequest, cfg *config.ModelConfig, ml *model.ModelLoader, cl *config.ModelConfigLoader, appConfig *config.ApplicationConfig, predInput string, openAIReq *schema.OpenAIRequest, funcs functions.Functions, shouldUseFn bool) error {
 	images := []string{}
 	for _, m := range openAIReq.Messages {
 		images = append(images, m.StringImages...)
 	}
 
+	toolsJSON := ""
+	if len(funcs) > 0 {
+		openAITools := make([]functions.Tool, len(funcs))
+		for i, f := range funcs {
+			openAITools[i] = functions.Tool{Type: "function", Function: f}
+		}
+		if toolsBytes, err := json.Marshal(openAITools); err == nil {
+			toolsJSON = string(toolsBytes)
+		}
+	}
+	toolChoiceJSON := ""
+	if input.ToolChoice != nil {
+		if toolChoiceBytes, err := json.Marshal(input.ToolChoice); err == nil {
+			toolChoiceJSON = string(toolChoiceBytes)
+		}
+	}
+
 	predFunc, err := backend.ModelInference(
-		input.Context, predInput, openAIReq.Messages, images, nil, nil, ml, cfg, nil, nil, nil, "", "", nil, nil, nil)
+		input.Context, predInput, openAIReq.Messages, images, nil, nil, ml, cfg, cl, appConfig, nil, toolsJSON, toolChoiceJSON, nil, nil, nil)
 	if err != nil {
 		xlog.Error("Anthropic model inference failed", "error", err)
 		return sendAnthropicError(c, 500, "api_error", fmt.Sprintf("model inference failed: %v", err))
@@ -175,7 +192,7 @@ func handleAnthropicNonStream(c echo.Context, id string, input *schema.Anthropic
 	return c.JSON(200, resp)
 }
 
-func handleAnthropicStream(c echo.Context, id string, input *schema.AnthropicRequest, cfg *config.ModelConfig, ml *model.ModelLoader, predInput string, openAIReq *schema.OpenAIRequest, funcs functions.Functions, shouldUseFn bool) error {
+func handleAnthropicStream(c echo.Context, id string, input *schema.AnthropicRequest, cfg *config.ModelConfig, ml *model.ModelLoader, cl *config.ModelConfigLoader, appConfig *config.ApplicationConfig, predInput string, openAIReq *schema.OpenAIRequest, funcs functions.Functions, shouldUseFn bool) error {
 	c.Response().Header().Set("Content-Type", "text/event-stream")
 	c.Response().Header().Set("Cache-Control", "no-cache")
 	c.Response().Header().Set("Connection", "keep-alive")
@@ -292,8 +309,25 @@ func handleAnthropicStream(c echo.Context, id string, input *schema.AnthropicReq
 		return true
 	}
 
+	toolsJSON := ""
+	if len(funcs) > 0 {
+		openAITools := make([]functions.Tool, len(funcs))
+		for i, f := range funcs {
+			openAITools[i] = functions.Tool{Type: "function", Function: f}
+		}
+		if toolsBytes, err := json.Marshal(openAITools); err == nil {
+			toolsJSON = string(toolsBytes)
+		}
+	}
+	toolChoiceJSON := ""
+	if input.ToolChoice != nil {
+		if toolChoiceBytes, err := json.Marshal(input.ToolChoice); err == nil {
+			toolChoiceJSON = string(toolChoiceBytes)
+		}
+	}
+
 	predFunc, err := backend.ModelInference(
-		input.Context, predInput, openAIMessages, images, nil, nil, ml, cfg, nil, nil, tokenCallback, "", "", nil, nil, nil)
+		input.Context, predInput, openAIMessages, images, nil, nil, ml, cfg, cl, appConfig, tokenCallback, toolsJSON, toolChoiceJSON, nil, nil, nil)
 	if err != nil {
 		xlog.Error("Anthropic stream model inference failed", "error", err)
 		return sendAnthropicError(c, 500, "api_error", fmt.Sprintf("model inference failed: %v", err))
@@ -367,10 +401,11 @@ func convertAnthropicToOpenAIMessages(input *schema.AnthropicRequest) []schema.M
 
 	// Add system message if present
 	if input.System != "" {
+		sysStr := string(input.System)
 		messages = append(messages, schema.Message{
 			Role:          "system",
-			StringContent: input.System,
-			Content:       input.System,
+			StringContent: sysStr,
+			Content:       sysStr,
 		})
 	}
 
diff --git a/core/schema/anthropic.go b/core/schema/anthropic.go
index d6c17ba79..a44ea64bd 100644
--- a/core/schema/anthropic.go
+++ b/core/schema/anthropic.go
@@ -5,16 +5,44 @@ import (
 	"encoding/json"
 )
 
+// AnthropicSystemParam accepts system as string or array of content blocks (SDK sends array).
+type AnthropicSystemParam string
+
+// UnmarshalJSON accepts string or array of blocks with "text" field.
+func (s *AnthropicSystemParam) UnmarshalJSON(data []byte) error {
+	var raw interface{}
+	if err := json.Unmarshal(data, &raw); err != nil {
+		return err
+	}
+	switch v := raw.(type) {
+	case string:
+		*s = AnthropicSystemParam(v)
+		return nil
+	case []interface{}:
+		var out string
+		for _, block := range v {
+			if m, ok := block.(map[string]interface{}); ok && m["type"] == "text" {
+				if t, ok := m["text"].(string); ok {
+					out += t
+				}
+			}
+		}
+		*s = AnthropicSystemParam(out)
+		return nil
+	}
+	return nil
+}
+
 // AnthropicRequest represents a request to the Anthropic Messages API
 // https://docs.anthropic.com/claude/reference/messages_post
 type AnthropicRequest struct {
-	Model         string             `json:"model"`
-	Messages      []AnthropicMessage `json:"messages"`
-	MaxTokens     int                `json:"max_tokens"`
-	Metadata      map[string]string  `json:"metadata,omitempty"`
-	StopSequences []string           `json:"stop_sequences,omitempty"`
-	Stream        bool               `json:"stream,omitempty"`
-	System        string             `json:"system,omitempty"`
+	Model         string                 `json:"model"`
+	Messages      []AnthropicMessage     `json:"messages"`
+	MaxTokens     int                    `json:"max_tokens"`
+	Metadata      map[string]string      `json:"metadata,omitempty"`
+	StopSequences []string               `json:"stop_sequences,omitempty"`
+	Stream        bool                   `json:"stream,omitempty"`
+	System        AnthropicSystemParam   `json:"system,omitempty"`
 	Temperature   *float64           `json:"temperature,omitempty"`
 	TopK          *int               `json:"top_k,omitempty"`
 	TopP          *float64           `json:"top_p,omitempty"`
diff --git a/core/schema/anthropic_test.go b/core/schema/anthropic_test.go
index 56f7bc5dd..440399d34 100644
--- a/core/schema/anthropic_test.go
+++ b/core/schema/anthropic_test.go
@@ -27,7 +27,7 @@ var _ = Describe("Anthropic Schema", func() {
 			Expect(req.Model).To(Equal("claude-3-sonnet-20240229"))
 			Expect(req.MaxTokens).To(Equal(1024))
 			Expect(len(req.Messages)).To(Equal(1))
-			Expect(req.System).To(Equal("You are a helpful assistant."))
+			Expect(string(req.System)).To(Equal("You are a helpful assistant."))
 			Expect(*req.Temperature).To(Equal(0.7))
 		})
 
diff --git a/tests/e2e-fixtures/gpu.yaml b/tests/e2e-fixtures/gpu.yaml
deleted file mode 100644
index 78d6d4edb..000000000
--- a/tests/e2e-fixtures/gpu.yaml
+++ /dev/null
@@ -1,17 +0,0 @@
-context_size: 2048
-mirostat: 2
-mirostat_tau: 5.0
-mirostat_eta: 0.1
-f16: true
-threads: 1
-gpu_layers: 90
-name: gpt-4
-mmap: true
-parameters:
-  model: ggllm-test-model.bin
-  rope_freq_base: 10000 
-  max_tokens: 20
-  rope_freq_scale: 1
-  temperature: 0.2
-  top_k: 40
-  top_p: 0.95
diff --git a/tests/e2e/e2e_anthropic_test.go b/tests/e2e/e2e_anthropic_test.go
index c4646cf14..bfebddd22 100644
--- a/tests/e2e/e2e_anthropic_test.go
+++ b/tests/e2e/e2e_anthropic_test.go
@@ -2,9 +2,11 @@ package e2e_test
 
 import (
 	"context"
+	"encoding/json"
 
 	"github.com/anthropics/anthropic-sdk-go"
 	"github.com/anthropics/anthropic-sdk-go/option"
+	"github.com/anthropics/anthropic-sdk-go/shared/constant"
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
 )
@@ -14,29 +16,16 @@ var _ = Describe("Anthropic API E2E test", func() {
 
 	Context("API with Anthropic SDK", func() {
 		BeforeEach(func() {
-			// Create Anthropic client pointing to LocalAI
 			client = anthropic.NewClient(
-				option.WithBaseURL(localAIURL),
-				option.WithAPIKey("test-api-key"), // LocalAI doesn't require a real API key
+				option.WithBaseURL(anthropicBaseURL),
+				option.WithAPIKey("test-api-key"),
 			)
-
-			// Wait for API to be ready by attempting a simple request
-			Eventually(func() error {
-				_, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
-					MaxTokens: 10,
-					Messages: []anthropic.MessageParam{
-						anthropic.NewUserMessage(anthropic.NewTextBlock("Hi")),
-					},
-				})
-				return err
-			}, "2m").ShouldNot(HaveOccurred())
 		})
 
 		Context("Non-streaming responses", func() {
 			It("generates a response for a simple message", func() {
 				message, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
+					Model:     "mock-model",
 					MaxTokens: 1024,
 					Messages: []anthropic.MessageParam{
 						anthropic.NewUserMessage(anthropic.NewTextBlock("How much is 2+2? Reply with just the number.")),
@@ -44,21 +33,19 @@ var _ = Describe("Anthropic API E2E test", func() {
 				})
 				Expect(err).ToNot(HaveOccurred())
 				Expect(message.Content).ToNot(BeEmpty())
-				// Role is a constant type that defaults to "assistant"
 				Expect(string(message.Role)).To(Equal("assistant"))
-				Expect(message.StopReason).To(Equal(anthropic.MessageStopReasonEndTurn))
+				Expect(string(message.StopReason)).To(Equal("end_turn"))
 				Expect(string(message.Type)).To(Equal("message"))
 
-				// Check that content contains text block with expected answer
 				Expect(len(message.Content)).To(BeNumerically(">=", 1))
 				textBlock := message.Content[0]
 				Expect(string(textBlock.Type)).To(Equal("text"))
-				Expect(textBlock.Text).To(Or(ContainSubstring("4"), ContainSubstring("four")))
+				Expect(textBlock.Text).To(ContainSubstring("mocked"))
 			})
 
 			It("handles system prompts", func() {
 				message, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
+					Model:     "mock-model",
 					MaxTokens: 1024,
 					System: []anthropic.TextBlockParam{
 						{Text: "You are a helpful assistant. Always respond in uppercase letters."},
@@ -74,7 +61,7 @@ var _ = Describe("Anthropic API E2E test", func() {
 
 			It("returns usage information", func() {
 				message, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
+					Model:     "mock-model",
 					MaxTokens: 100,
 					Messages: []anthropic.MessageParam{
 						anthropic.NewUserMessage(anthropic.NewTextBlock("Hello")),
@@ -89,7 +76,7 @@ var _ = Describe("Anthropic API E2E test", func() {
 		Context("Streaming responses", func() {
 			It("streams tokens for a simple message", func() {
 				stream := client.Messages.NewStreaming(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
+					Model:     "mock-model",
 					MaxTokens: 1024,
 					Messages: []anthropic.MessageParam{
 						anthropic.NewUserMessage(anthropic.NewTextBlock("Count from 1 to 5")),
@@ -125,7 +112,7 @@ var _ = Describe("Anthropic API E2E test", func() {
 
 			It("streams with system prompt", func() {
 				stream := client.Messages.NewStreaming(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
+					Model:     "mock-model",
 					MaxTokens: 1024,
 					System: []anthropic.TextBlockParam{
 						{Text: "You are a helpful assistant."},
@@ -150,25 +137,27 @@ var _ = Describe("Anthropic API E2E test", func() {
 		Context("Tool calling", func() {
 			It("handles tool calls in non-streaming mode", func() {
 				message, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
+					Model:     "mock-model",
 					MaxTokens: 1024,
 					Messages: []anthropic.MessageParam{
 						anthropic.NewUserMessage(anthropic.NewTextBlock("What's the weather like in San Francisco?")),
 					},
-					Tools: []anthropic.ToolParam{
-						{
-							Name:        "get_weather",
-							Description: anthropic.F("Get the current weather in a given location"),
-							InputSchema: anthropic.F(map[string]interface{}{
-								"type": "object",
-								"properties": map[string]interface{}{
-									"location": map[string]interface{}{
-										"type":        "string",
-										"description": "The city and state, e.g. San Francisco, CA",
+					Tools: []anthropic.ToolUnionParam{
+						anthropic.ToolUnionParam{
+							OfTool: &anthropic.ToolParam{
+								Name:        "get_weather",
+								Description: anthropic.Opt("Get the current weather in a given location"),
+								InputSchema: anthropic.ToolInputSchemaParam{
+									Type: constant.ValueOf[constant.Object](),
+									Properties: map[string]interface{}{
+										"location": map[string]interface{}{
+											"type":        "string",
+											"description": "The city and state, e.g. San Francisco, CA",
+										},
 									},
+									Required: []string{"location"},
 								},
-								"required": []string{"location"},
-							}),
+							},
 						},
 					},
 				})
@@ -179,13 +168,14 @@ var _ = Describe("Anthropic API E2E test", func() {
 				// The model must use tools - find the tool use in the response
 				hasToolUse := false
 				for _, block := range message.Content {
-					if block.Type == anthropic.ContentBlockTypeToolUse {
+					if block.Type == "tool_use" {
 						hasToolUse = true
 						Expect(block.Name).To(Equal("get_weather"))
 						Expect(block.ID).ToNot(BeEmpty())
 						// Verify that input contains location
-						inputMap, ok := block.Input.(map[string]interface{})
-						Expect(ok).To(BeTrue())
+						var inputMap map[string]interface{}
+						err := json.Unmarshal(block.Input, &inputMap)
+						Expect(err).ToNot(HaveOccurred())
 						_, hasLocation := inputMap["location"]
 						Expect(hasLocation).To(BeTrue())
 					}
@@ -193,35 +183,37 @@ var _ = Describe("Anthropic API E2E test", func() {
 
 				// Model must have called the tool
 				Expect(hasToolUse).To(BeTrue(), "Model should have called the get_weather tool")
-				Expect(message.StopReason).To(Equal(anthropic.MessageStopReasonToolUse))
+				Expect(string(message.StopReason)).To(Equal("tool_use"))
 			})
 
 			It("handles tool_choice parameter", func() {
 				message, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
+					Model:     "mock-model",
 					MaxTokens: 1024,
 					Messages: []anthropic.MessageParam{
 						anthropic.NewUserMessage(anthropic.NewTextBlock("Tell me about the weather")),
 					},
-					Tools: []anthropic.ToolParam{
-						{
-							Name:        "get_weather",
-							Description: anthropic.F("Get the current weather"),
-							InputSchema: anthropic.F(map[string]interface{}{
-								"type": "object",
-								"properties": map[string]interface{}{
-									"location": map[string]interface{}{
-										"type": "string",
+					Tools: []anthropic.ToolUnionParam{
+						anthropic.ToolUnionParam{
+							OfTool: &anthropic.ToolParam{
+								Name:        "get_weather",
+								Description: anthropic.Opt("Get the current weather"),
+								InputSchema: anthropic.ToolInputSchemaParam{
+									Type: constant.ValueOf[constant.Object](),
+									Properties: map[string]interface{}{
+										"location": map[string]interface{}{
+											"type": "string",
+										},
 									},
 								},
-							}),
+							},
 						},
 					},
-					ToolChoice: anthropic.F[anthropic.ToolChoiceUnionParam](
-						anthropic.ToolChoiceAutoParam{
-							Type: anthropic.F(anthropic.ToolChoiceAutoTypeAuto),
+					ToolChoice: anthropic.ToolChoiceUnionParam{
+						OfAuto: &anthropic.ToolChoiceAutoParam{
+							Type: constant.ValueOf[constant.Auto](),
 						},
-					),
+					},
 				})
 
 				Expect(err).ToNot(HaveOccurred())
@@ -231,21 +223,23 @@ var _ = Describe("Anthropic API E2E test", func() {
 			It("handles tool results in messages", func() {
 				// First, make a request that should trigger a tool call
 				firstMessage, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
+					Model:     "mock-model",
 					MaxTokens: 1024,
 					Messages: []anthropic.MessageParam{
 						anthropic.NewUserMessage(anthropic.NewTextBlock("What's the weather in SF?")),
 					},
-					Tools: []anthropic.ToolParam{
-						{
-							Name:        "get_weather",
-							Description: anthropic.F("Get weather"),
-							InputSchema: anthropic.F(map[string]interface{}{
-								"type": "object",
-								"properties": map[string]interface{}{
-									"location": map[string]interface{}{"type": "string"},
+					Tools: []anthropic.ToolUnionParam{
+						anthropic.ToolUnionParam{
+							OfTool: &anthropic.ToolParam{
+								Name:        "get_weather",
+								Description: anthropic.Opt("Get weather"),
+								InputSchema: anthropic.ToolInputSchemaParam{
+									Type: constant.ValueOf[constant.Object](),
+									Properties: map[string]interface{}{
+										"location": map[string]interface{}{"type": "string"},
+									},
 								},
-							}),
+							},
 						},
 					},
 				})
@@ -256,7 +250,7 @@ var _ = Describe("Anthropic API E2E test", func() {
 				var toolUseID string
 				var toolUseName string
 				for _, block := range firstMessage.Content {
-					if block.Type == anthropic.ContentBlockTypeToolUse {
+					if block.Type == "tool_use" {
 						toolUseID = block.ID
 						toolUseName = block.Name
 						break
@@ -266,27 +260,44 @@ var _ = Describe("Anthropic API E2E test", func() {
 				// Model must have called the tool
 				Expect(toolUseID).ToNot(BeEmpty(), "Model should have called the get_weather tool")
 
+				// Convert ContentBlockUnion to ContentBlockParamUnion for NewAssistantMessage
+				contentBlocks := make([]anthropic.ContentBlockParamUnion, len(firstMessage.Content))
+				for i, block := range firstMessage.Content {
+					if block.Type == "tool_use" {
+						var inputMap map[string]interface{}
+						if err := json.Unmarshal(block.Input, &inputMap); err == nil {
+							contentBlocks[i] = anthropic.NewToolUseBlock(block.ID, inputMap, block.Name)
+						} else {
+							contentBlocks[i] = anthropic.NewToolUseBlock(block.ID, block.Input, block.Name)
+						}
+					} else if block.Type == "text" {
+						contentBlocks[i] = anthropic.NewTextBlock(block.Text)
+					}
+				}
+
 				// Send back a tool result and verify it's handled correctly
 				secondMessage, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
+					Model:     "mock-model",
 					MaxTokens: 1024,
 					Messages: []anthropic.MessageParam{
 						anthropic.NewUserMessage(anthropic.NewTextBlock("What's the weather in SF?")),
-						anthropic.NewAssistantMessage(firstMessage.Content...),
+						anthropic.NewAssistantMessage(contentBlocks...),
 						anthropic.NewUserMessage(
 							anthropic.NewToolResultBlock(toolUseID, "Sunny, 72°F", false),
 						),
 					},
-					Tools: []anthropic.ToolParam{
-						{
-							Name:        toolUseName,
-							Description: anthropic.F("Get weather"),
-							InputSchema: anthropic.F(map[string]interface{}{
-								"type": "object",
-								"properties": map[string]interface{}{
-									"location": map[string]interface{}{"type": "string"},
+					Tools: []anthropic.ToolUnionParam{
+						anthropic.ToolUnionParam{
+							OfTool: &anthropic.ToolParam{
+								Name:        toolUseName,
+								Description: anthropic.Opt("Get weather"),
+								InputSchema: anthropic.ToolInputSchemaParam{
+									Type: constant.ValueOf[constant.Object](),
+									Properties: map[string]interface{}{
+										"location": map[string]interface{}{"type": "string"},
+									},
 								},
-							}),
+							},
 						},
 					},
 				})
@@ -297,32 +308,33 @@ var _ = Describe("Anthropic API E2E test", func() {
 
 			It("handles tool calls in streaming mode", func() {
 				stream := client.Messages.NewStreaming(context.TODO(), anthropic.MessageNewParams{
-					Model:     "gpt-4",
+					Model:     "mock-model",
 					MaxTokens: 1024,
 					Messages: []anthropic.MessageParam{
 						anthropic.NewUserMessage(anthropic.NewTextBlock("What's the weather like in San Francisco?")),
 					},
-					Tools: []anthropic.ToolParam{
-						{
-							Name:        "get_weather",
-							Description: anthropic.F("Get the current weather in a given location"),
-							InputSchema: anthropic.F(map[string]interface{}{
-								"type": "object",
-								"properties": map[string]interface{}{
-									"location": map[string]interface{}{
-										"type":        "string",
-										"description": "The city and state, e.g. San Francisco, CA",
+					Tools: []anthropic.ToolUnionParam{
+						anthropic.ToolUnionParam{
+							OfTool: &anthropic.ToolParam{
+								Name:        "get_weather",
+								Description: anthropic.Opt("Get the current weather in a given location"),
+								InputSchema: anthropic.ToolInputSchemaParam{
+									Type: constant.ValueOf[constant.Object](),
+									Properties: map[string]interface{}{
+										"location": map[string]interface{}{
+											"type":        "string",
+											"description": "The city and state, e.g. San Francisco, CA",
+										},
 									},
+									Required: []string{"location"},
 								},
-								"required": []string{"location"},
-							}),
+							},
 						},
 					},
 				})
 
 				message := anthropic.Message{}
 				eventCount := 0
-				hasToolUseBlock := false
 				hasContentBlockStart := false
 				hasContentBlockDelta := false
 				hasContentBlockStop := false
@@ -337,8 +349,8 @@ var _ = Describe("Anthropic API E2E test", func() {
 					switch e := event.AsAny().(type) {
 					case anthropic.ContentBlockStartEvent:
 						hasContentBlockStart = true
-						if e.ContentBlock.Type == anthropic.ContentBlockTypeToolUse {
-							hasToolUseBlock = true
+						if e.ContentBlock.Type == "tool_use" {
+							// Tool use block detected
 						}
 					case anthropic.ContentBlockDeltaEvent:
 						hasContentBlockDelta = true
@@ -357,18 +369,18 @@ var _ = Describe("Anthropic API E2E test", func() {
 
 				// Check accumulated message has tool use
 				Expect(message.Content).ToNot(BeEmpty())
-				
+
 				// Model must have called the tool
 				foundToolUse := false
 				for _, block := range message.Content {
-					if block.Type == anthropic.ContentBlockTypeToolUse {
+					if block.Type == "tool_use" {
 						foundToolUse = true
 						Expect(block.Name).To(Equal("get_weather"))
 						Expect(block.ID).ToNot(BeEmpty())
 					}
 				}
 				Expect(foundToolUse).To(BeTrue(), "Model should have called the get_weather tool in streaming mode")
-				Expect(message.StopReason).To(Equal(anthropic.MessageStopReasonToolUse))
+				Expect(string(message.StopReason)).To(Equal("tool_use"))
 			})
 		})
 	})
diff --git a/tests/e2e/e2e_suite_test.go b/tests/e2e/e2e_suite_test.go
index f6ab238df..85d136d3e 100644
--- a/tests/e2e/e2e_suite_test.go
+++ b/tests/e2e/e2e_suite_test.go
@@ -1,17 +1,170 @@
 package e2e_test
 
 import (
+	"context"
+	"fmt"
+	"net/http"
 	"os"
+	"path/filepath"
 	"testing"
+	"time"
 
+	"github.com/labstack/echo/v4"
+	"github.com/mudler/LocalAI/core/application"
+	"github.com/mudler/LocalAI/core/config"
+	httpapi "github.com/mudler/LocalAI/core/http"
+	"github.com/mudler/LocalAI/pkg/system"
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
+	"github.com/phayes/freeport"
+	"github.com/sashabaranov/go-openai"
+	"gopkg.in/yaml.v3"
+
+	"github.com/mudler/xlog"
 )
 
 var (
-	localAIURL = os.Getenv("LOCALAI_API")
+	localAIURL       string
+	anthropicBaseURL string
+	tmpDir           string
+	backendPath    string
+	modelsPath     string
+	configPath     string
+	app            *echo.Echo
+	appCtx         context.Context
+	appCancel      context.CancelFunc
+	client         *openai.Client
+	apiPort        int
+	apiURL         string
+	mockBackendPath string
 )
 
+var _ = BeforeSuite(func() {
+	var err error
+
+	// Create temporary directory
+	tmpDir, err = os.MkdirTemp("", "mock-backend-e2e-*")
+	Expect(err).ToNot(HaveOccurred())
+
+	backendPath = filepath.Join(tmpDir, "backends")
+	modelsPath = filepath.Join(tmpDir, "models")
+	Expect(os.MkdirAll(backendPath, 0755)).To(Succeed())
+	Expect(os.MkdirAll(modelsPath, 0755)).To(Succeed())
+
+	// Build mock backend
+	mockBackendDir := filepath.Join("..", "e2e", "mock-backend")
+	mockBackendPath = filepath.Join(backendPath, "mock-backend")
+
+	// Check if mock-backend binary exists in the mock-backend directory
+	possiblePaths := []string{
+		filepath.Join(mockBackendDir, "mock-backend"),
+		filepath.Join("tests", "e2e", "mock-backend", "mock-backend"),
+		filepath.Join("..", "..", "tests", "e2e", "mock-backend", "mock-backend"),
+	}
+
+	found := false
+	for _, p := range possiblePaths {
+		if _, err := os.Stat(p); err == nil {
+			mockBackendPath = p
+			found = true
+			break
+		}
+	}
+
+	if !found {
+		// Try to find it relative to current working directory
+		wd, _ := os.Getwd()
+		relPath := filepath.Join(wd, "..", "..", "tests", "e2e", "mock-backend", "mock-backend")
+		if _, err := os.Stat(relPath); err == nil {
+			mockBackendPath = relPath
+			found = true
+		}
+	}
+
+	Expect(found).To(BeTrue(), "mock-backend binary not found. Run 'make build-mock-backend' first")
+
+	// Make sure it's executable
+	Expect(os.Chmod(mockBackendPath, 0755)).To(Succeed())
+
+	// Create model config YAML
+	modelConfig := map[string]interface{}{
+		"name":    "mock-model",
+		"backend": "mock-backend",
+		"parameters": map[string]interface{}{
+			"model": "mock-model.bin",
+		},
+	}
+	configPath = filepath.Join(modelsPath, "mock-model.yaml")
+	configYAML, err := yaml.Marshal(modelConfig)
+	Expect(err).ToNot(HaveOccurred())
+	Expect(os.WriteFile(configPath, configYAML, 0644)).To(Succeed())
+
+	// Set up system state
+	systemState, err := system.GetSystemState(
+		system.WithBackendPath(backendPath),
+		system.WithModelPath(modelsPath),
+	)
+	Expect(err).ToNot(HaveOccurred())
+
+	// Create application
+	appCtx, appCancel = context.WithCancel(context.Background())
+
+	// Create application instance
+	application, err := application.New(
+		config.WithContext(appCtx),
+		config.WithSystemState(systemState),
+		config.WithDebug(true),
+	)
+	Expect(err).ToNot(HaveOccurred())
+
+	// Register backend with application's model loader
+	application.ModelLoader().SetExternalBackend("mock-backend", mockBackendPath)
+
+	// Create HTTP app
+	app, err = httpapi.API(application)
+	Expect(err).ToNot(HaveOccurred())
+
+	// Get free port
+	port, err := freeport.GetFreePort()
+	Expect(err).ToNot(HaveOccurred())
+	apiPort = port
+	apiURL = fmt.Sprintf("http://127.0.0.1:%d/v1", apiPort)
+	localAIURL = apiURL
+	// Anthropic SDK appends /v1/messages to base URL; use base without /v1 so requests go to /v1/messages
+	anthropicBaseURL = fmt.Sprintf("http://127.0.0.1:%d", apiPort)
+
+	// Start server in goroutine
+	go func() {
+		if err := app.Start(fmt.Sprintf("127.0.0.1:%d", apiPort)); err != nil && err != http.ErrServerClosed {
+			xlog.Error("server error", "error", err)
+		}
+	}()
+
+	// Wait for server to be ready
+	defaultConfig := openai.DefaultConfig("")
+	defaultConfig.BaseURL = apiURL
+	client = openai.NewClientWithConfig(defaultConfig)
+
+	Eventually(func() error {
+		_, err := client.ListModels(context.TODO())
+		return err
+	}, "2m").ShouldNot(HaveOccurred())
+})
+
+var _ = AfterSuite(func() {
+	if appCancel != nil {
+		appCancel()
+	}
+	if app != nil {
+		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+		Expect(app.Shutdown(ctx)).To(Succeed())
+	}
+	if tmpDir != "" {
+		os.RemoveAll(tmpDir)
+	}
+})
+
 func TestLocalAI(t *testing.T) {
 	RegisterFailHandler(Fail)
 	RunSpecs(t, "LocalAI E2E test suite")
diff --git a/tests/e2e/e2e_test.go b/tests/e2e/e2e_test.go
deleted file mode 100644
index 7b506e609..000000000
--- a/tests/e2e/e2e_test.go
+++ /dev/null
@@ -1,70 +0,0 @@
-package e2e_test
-
-import (
-	"context"
-	"fmt"
-	"os"
-	"os/exec"
-
-	. "github.com/onsi/ginkgo/v2"
-	. "github.com/onsi/gomega"
-
-	openaigo "github.com/otiai10/openaigo"
-	"github.com/sashabaranov/go-openai"
-)
-
-var _ = Describe("E2E test", func() {
-	var client *openai.Client
-	var client2 *openaigo.Client
-
-	Context("API with ephemeral models", func() {
-		BeforeEach(func() {
-			defaultConfig := openai.DefaultConfig("")
-			defaultConfig.BaseURL = localAIURL
-
-			client2 = openaigo.NewClient("")
-			client2.BaseURL = defaultConfig.BaseURL
-
-			// Wait for API to be ready
-			client = openai.NewClientWithConfig(defaultConfig)
-			Eventually(func() error {
-				_, err := client.ListModels(context.TODO())
-				return err
-			}, "2m").ShouldNot(HaveOccurred())
-		})
-
-		// Check that the GPU was used
-		AfterEach(func() {
-			cmd := exec.Command("/bin/bash", "-xce", "docker logs $(docker ps -q --filter ancestor=localai-tests)")
-			out, err := cmd.CombinedOutput()
-			Expect(err).ToNot(HaveOccurred(), string(out))
-			// Execute docker logs $$(docker ps -q --filter ancestor=localai-tests) as a command and check the output
-			if os.Getenv("BUILD_TYPE") == "cublas" {
-
-				Expect(string(out)).To(ContainSubstring("found 1 CUDA devices"), string(out))
-				Expect(string(out)).To(ContainSubstring("using CUDA for GPU acceleration"), string(out))
-			} else {
-				fmt.Println("Skipping GPU check")
-				Expect(string(out)).To(ContainSubstring("[llama-cpp] Loads OK"), string(out))
-				Expect(string(out)).To(ContainSubstring("llama_model_loader"), string(out))
-			}
-		})
-
-		Context("Generates text", func() {
-			It("streams chat tokens", func() {
-				model := "gpt-4"
-				resp, err := client.CreateChatCompletion(context.TODO(),
-					openai.ChatCompletionRequest{
-						Model: model, Messages: []openai.ChatCompletionMessage{
-							{
-								Role:    "user",
-								Content: "How much is 2+2?",
-							},
-						}})
-				Expect(err).ToNot(HaveOccurred())
-				Expect(len(resp.Choices)).To(Equal(1), fmt.Sprint(resp))
-				Expect(resp.Choices[0].Message.Content).To(Or(ContainSubstring("4"), ContainSubstring("four")), fmt.Sprint(resp.Choices[0].Message.Content))
-			})
-		})
-	})
-})
diff --git a/tests/e2e/mock-backend/.gitignore b/tests/e2e/mock-backend/.gitignore
new file mode 100644
index 000000000..32923bce6
--- /dev/null
+++ b/tests/e2e/mock-backend/.gitignore
@@ -0,0 +1 @@
+mock-backend
\ No newline at end of file
diff --git a/tests/e2e/mock-backend/Makefile b/tests/e2e/mock-backend/Makefile
new file mode 100644
index 000000000..02ef0a46b
--- /dev/null
+++ b/tests/e2e/mock-backend/Makefile
@@ -0,0 +1,7 @@
+.PHONY: build clean
+
+build:
+	cd ../../.. && go build -o tests/e2e/mock-backend/mock-backend ./tests/e2e/mock-backend
+
+clean:
+	rm -f mock-backend
diff --git a/tests/e2e/mock-backend/main.go b/tests/e2e/mock-backend/main.go
new file mode 100644
index 000000000..824474613
--- /dev/null
+++ b/tests/e2e/mock-backend/main.go
@@ -0,0 +1,334 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"log"
+	"net"
+	"os"
+
+	pb "github.com/mudler/LocalAI/pkg/grpc/proto"
+	"github.com/mudler/xlog"
+	"google.golang.org/grpc"
+)
+
+var (
+	addr = flag.String("addr", "localhost:50051", "the address to connect to")
+)
+
+// MockBackend implements the Backend gRPC service with mocked responses
+type MockBackend struct {
+	pb.UnimplementedBackendServer
+}
+
+func (m *MockBackend) Health(ctx context.Context, in *pb.HealthMessage) (*pb.Reply, error) {
+	xlog.Debug("Health check called")
+	return &pb.Reply{Message: []byte("OK")}, nil
+}
+
+func (m *MockBackend) LoadModel(ctx context.Context, in *pb.ModelOptions) (*pb.Result, error) {
+	xlog.Debug("LoadModel called", "model", in.Model)
+	return &pb.Result{
+		Message: "Model loaded successfully (mocked)",
+		Success: true,
+	}, nil
+}
+
+func (m *MockBackend) Predict(ctx context.Context, in *pb.PredictOptions) (*pb.Reply, error) {
+	xlog.Debug("Predict called", "prompt", in.Prompt)
+	var response string
+	toolName := mockToolNameFromRequest(in)
+	if toolName != "" {
+		response = fmt.Sprintf(`{"name": "%s", "arguments": {"location": "San Francisco"}}`, toolName)
+	} else {
+		response = "This is a mocked response."
+	}
+	return &pb.Reply{
+		Message:                 []byte(response),
+		Tokens:                  10,
+		PromptTokens:            5,
+		TimingPromptProcessing:  0.1,
+		TimingTokenGeneration:   0.2,
+	}, nil
+}
+
+func (m *MockBackend) PredictStream(in *pb.PredictOptions, stream pb.Backend_PredictStreamServer) error {
+	xlog.Debug("PredictStream called", "prompt", in.Prompt)
+	var toStream string
+	toolName := mockToolNameFromRequest(in)
+	if toolName != "" {
+		toStream = fmt.Sprintf(`{"name": "%s", "arguments": {"location": "San Francisco"}}`, toolName)
+	} else {
+		toStream = "This is a mocked streaming response."
+	}
+	for i, r := range toStream {
+		if err := stream.Send(&pb.Reply{
+			Message: []byte(string(r)),
+			Tokens:  int32(i + 1),
+		}); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// mockToolNameFromRequest returns the first tool name from the request's Tools JSON (same as other endpoints).
+func mockToolNameFromRequest(in *pb.PredictOptions) string {
+	if in.Tools == "" {
+		return ""
+	}
+	var tools []struct {
+		Function struct {
+			Name string `json:"name"`
+		} `json:"function"`
+	}
+	if err := json.Unmarshal([]byte(in.Tools), &tools); err != nil || len(tools) == 0 || tools[0].Function.Name == "" {
+		return ""
+	}
+	return tools[0].Function.Name
+}
+
+func (m *MockBackend) Embedding(ctx context.Context, in *pb.PredictOptions) (*pb.EmbeddingResult, error) {
+	xlog.Debug("Embedding called", "prompt", in.Prompt)
+	// Return a mock embedding vector of 768 dimensions
+	embeddings := make([]float32, 768)
+	for i := range embeddings {
+		embeddings[i] = float32(i%100) / 100.0 // Pattern: 0.0, 0.01, 0.02, ..., 0.99, 0.0, ...
+	}
+	return &pb.EmbeddingResult{Embeddings: embeddings}, nil
+}
+
+func (m *MockBackend) GenerateImage(ctx context.Context, in *pb.GenerateImageRequest) (*pb.Result, error) {
+	xlog.Debug("GenerateImage called", "prompt", in.PositivePrompt)
+	return &pb.Result{
+		Message: "Image generated successfully (mocked)",
+		Success: true,
+	}, nil
+}
+
+func (m *MockBackend) GenerateVideo(ctx context.Context, in *pb.GenerateVideoRequest) (*pb.Result, error) {
+	xlog.Debug("GenerateVideo called", "prompt", in.Prompt)
+	return &pb.Result{
+		Message: "Video generated successfully (mocked)",
+		Success: true,
+	}, nil
+}
+
+func (m *MockBackend) TTS(ctx context.Context, in *pb.TTSRequest) (*pb.Result, error) {
+	xlog.Debug("TTS called", "text", in.Text)
+	// Return success - actual audio would be in the Result message for real backends
+	return &pb.Result{
+		Message: "TTS audio generated successfully (mocked)",
+		Success: true,
+	}, nil
+}
+
+func (m *MockBackend) TTSStream(in *pb.TTSRequest, stream pb.Backend_TTSStreamServer) error {
+	xlog.Debug("TTSStream called", "text", in.Text)
+	// Stream mock audio chunks (simplified - just send a few bytes)
+	chunks := [][]byte{
+		{0x52, 0x49, 0x46, 0x46}, // Mock WAV header start
+		{0x57, 0x41, 0x56, 0x45}, // Mock WAV header
+		{0x64, 0x61, 0x74, 0x61}, // Mock data chunk
+	}
+	for _, chunk := range chunks {
+		if err := stream.Send(&pb.Reply{Audio: chunk}); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (m *MockBackend) SoundGeneration(ctx context.Context, in *pb.SoundGenerationRequest) (*pb.Result, error) {
+	xlog.Debug("SoundGeneration called", "text", in.Text)
+	return &pb.Result{
+		Message: "Sound generated successfully (mocked)",
+		Success: true,
+	}, nil
+}
+
+func (m *MockBackend) AudioTranscription(ctx context.Context, in *pb.TranscriptRequest) (*pb.TranscriptResult, error) {
+	xlog.Debug("AudioTranscription called")
+	return &pb.TranscriptResult{
+		Text: "This is a mocked transcription.",
+		Segments: []*pb.TranscriptSegment{
+			{
+				Id:    0,
+				Start: 0,
+				End:   3000,
+				Text:  "This is a mocked transcription.",
+				Tokens: []int32{1, 2, 3, 4, 5, 6},
+			},
+		},
+	}, nil
+}
+
+func (m *MockBackend) TokenizeString(ctx context.Context, in *pb.PredictOptions) (*pb.TokenizationResponse, error) {
+	xlog.Debug("TokenizeString called", "prompt", in.Prompt)
+	// Return mock token IDs
+	tokens := []int32{101, 2023, 2003, 1037, 3231, 1012}
+	return &pb.TokenizationResponse{
+		Length: int32(len(tokens)),
+		Tokens:  tokens,
+	}, nil
+}
+
+func (m *MockBackend) Status(ctx context.Context, in *pb.HealthMessage) (*pb.StatusResponse, error) {
+	xlog.Debug("Status called")
+	return &pb.StatusResponse{
+		State: pb.StatusResponse_READY,
+		Memory: &pb.MemoryUsageData{
+			Total: 1024 * 1024 * 100, // 100MB
+			Breakdown: map[string]uint64{
+				"mock": 1024 * 1024 * 50,
+			},
+		},
+	}, nil
+}
+
+func (m *MockBackend) Detect(ctx context.Context, in *pb.DetectOptions) (*pb.DetectResponse, error) {
+	xlog.Debug("Detect called", "src", in.Src)
+	return &pb.DetectResponse{
+		Detections: []*pb.Detection{
+			{
+				X:         10.0,
+				Y:         20.0,
+				Width:     100.0,
+				Height:    200.0,
+				Confidence: 0.95,
+				ClassName: "mocked_object",
+			},
+		},
+	}, nil
+}
+
+func (m *MockBackend) StoresSet(ctx context.Context, in *pb.StoresSetOptions) (*pb.Result, error) {
+	xlog.Debug("StoresSet called", "keys", len(in.Keys))
+	return &pb.Result{
+		Message: "Keys set successfully (mocked)",
+		Success: true,
+	}, nil
+}
+
+func (m *MockBackend) StoresDelete(ctx context.Context, in *pb.StoresDeleteOptions) (*pb.Result, error) {
+	xlog.Debug("StoresDelete called", "keys", len(in.Keys))
+	return &pb.Result{
+		Message: "Keys deleted successfully (mocked)",
+		Success: true,
+	}, nil
+}
+
+func (m *MockBackend) StoresGet(ctx context.Context, in *pb.StoresGetOptions) (*pb.StoresGetResult, error) {
+	xlog.Debug("StoresGet called", "keys", len(in.Keys))
+	// Return mock keys and values
+	keys := make([]*pb.StoresKey, len(in.Keys))
+	values := make([]*pb.StoresValue, len(in.Keys))
+	for i := range in.Keys {
+		keys[i] = in.Keys[i]
+		values[i] = &pb.StoresValue{
+			Bytes: []byte(fmt.Sprintf("mocked_value_%d", i)),
+		}
+	}
+	return &pb.StoresGetResult{
+		Keys:   keys,
+		Values: values,
+	}, nil
+}
+
+func (m *MockBackend) StoresFind(ctx context.Context, in *pb.StoresFindOptions) (*pb.StoresFindResult, error) {
+	xlog.Debug("StoresFind called", "topK", in.TopK)
+	// Return mock similar keys
+	keys := []*pb.StoresKey{
+		{Floats: []float32{0.1, 0.2, 0.3}},
+		{Floats: []float32{0.4, 0.5, 0.6}},
+	}
+	values := []*pb.StoresValue{
+		{Bytes: []byte("mocked_value_1")},
+		{Bytes: []byte("mocked_value_2")},
+	}
+	similarities := []float32{0.95, 0.85}
+	return &pb.StoresFindResult{
+		Keys:        keys,
+		Values:      values,
+		Similarities: similarities,
+	}, nil
+}
+
+func (m *MockBackend) Rerank(ctx context.Context, in *pb.RerankRequest) (*pb.RerankResult, error) {
+	xlog.Debug("Rerank called", "query", in.Query, "documents", len(in.Documents))
+	// Return mock reranking results
+	results := make([]*pb.DocumentResult, len(in.Documents))
+	for i, doc := range in.Documents {
+		results[i] = &pb.DocumentResult{
+			Index:          int32(i),
+			Text:           doc,
+			RelevanceScore: 0.9 - float32(i)*0.1, // Decreasing scores
+		}
+	}
+	return &pb.RerankResult{
+		Usage: &pb.Usage{
+			TotalTokens:  int32(len(in.Documents) * 10),
+			PromptTokens: int32(len(in.Documents) * 10),
+		},
+		Results: results,
+	}, nil
+}
+
+func (m *MockBackend) GetMetrics(ctx context.Context, in *pb.MetricsRequest) (*pb.MetricsResponse, error) {
+	xlog.Debug("GetMetrics called")
+	return &pb.MetricsResponse{
+		SlotId:              0,
+		PromptJsonForSlot:   `{"prompt":"mocked"}`,
+		TokensPerSecond:     10.0,
+		TokensGenerated:     100,
+		PromptTokensProcessed: 50,
+	}, nil
+}
+
+func (m *MockBackend) VAD(ctx context.Context, in *pb.VADRequest) (*pb.VADResponse, error) {
+	xlog.Debug("VAD called", "audio_length", len(in.Audio))
+	return &pb.VADResponse{
+		Segments: []*pb.VADSegment{
+			{
+				Start: 0.0,
+				End:   1.5,
+			},
+			{
+				Start: 2.0,
+				End:   3.5,
+			},
+		},
+	}, nil
+}
+
+func (m *MockBackend) ModelMetadata(ctx context.Context, in *pb.ModelOptions) (*pb.ModelMetadataResponse, error) {
+	xlog.Debug("ModelMetadata called", "model", in.Model)
+	return &pb.ModelMetadataResponse{
+		SupportsThinking: false,
+		RenderedTemplate: "",
+	}, nil
+}
+
+func main() {
+	xlog.SetLogger(xlog.NewLogger(xlog.LogLevel(os.Getenv("LOCALAI_LOG_LEVEL")), os.Getenv("LOCALAI_LOG_FORMAT")))
+
+	flag.Parse()
+
+	lis, err := net.Listen("tcp", *addr)
+	if err != nil {
+		log.Fatalf("failed to listen: %v", err)
+	}
+
+	s := grpc.NewServer(
+		grpc.MaxRecvMsgSize(50*1024*1024), // 50MB
+		grpc.MaxSendMsgSize(50*1024*1024), // 50MB
+	)
+	pb.RegisterBackendServer(s, &MockBackend{})
+
+	xlog.Info("Mock gRPC Server listening", "address", lis.Addr())
+	if err := s.Serve(lis); err != nil {
+		log.Fatalf("failed to serve: %v", err)
+	}
+}
diff --git a/tests/e2e/mock_backend_test.go b/tests/e2e/mock_backend_test.go
new file mode 100644
index 000000000..0585209dd
--- /dev/null
+++ b/tests/e2e/mock_backend_test.go
@@ -0,0 +1,185 @@
+package e2e_test
+
+import (
+	"context"
+	"io"
+	"net/http"
+	"strings"
+	"time"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	"github.com/sashabaranov/go-openai"
+)
+
+var _ = Describe("Mock Backend E2E Tests", Label("MockBackend"), func() {
+	Describe("Text Generation APIs", func() {
+		Context("Predict (Chat Completions)", func() {
+			It("should return mocked response", func() {
+				resp, err := client.CreateChatCompletion(
+					context.TODO(),
+					openai.ChatCompletionRequest{
+						Model: "mock-model",
+						Messages: []openai.ChatCompletionMessage{
+							{
+								Role:    "user",
+								Content: "Hello",
+							},
+						},
+					},
+				)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(len(resp.Choices)).To(Equal(1))
+				Expect(resp.Choices[0].Message.Content).To(ContainSubstring("mocked response"))
+			})
+		})
+
+		Context("PredictStream (Streaming Chat Completions)", func() {
+			It("should stream mocked tokens", func() {
+				stream, err := client.CreateChatCompletionStream(
+					context.TODO(),
+					openai.ChatCompletionRequest{
+						Model: "mock-model",
+						Messages: []openai.ChatCompletionMessage{
+							{
+								Role:    "user",
+								Content: "Hello",
+							},
+						},
+					},
+				)
+				Expect(err).ToNot(HaveOccurred())
+				defer stream.Close()
+
+				hasContent := false
+				for {
+					response, err := stream.Recv()
+					if err != nil {
+						break
+					}
+					if len(response.Choices) > 0 && response.Choices[0].Delta.Content != "" {
+						hasContent = true
+					}
+				}
+				Expect(hasContent).To(BeTrue())
+			})
+		})
+	})
+
+	Describe("Embeddings API", func() {
+		It("should return mocked embeddings", func() {
+			resp, err := client.CreateEmbeddings(
+				context.TODO(),
+				openai.EmbeddingRequest{
+					Model: "mock-model",
+					Input: []string{"test"},
+				},
+			)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(len(resp.Data)).To(Equal(1))
+			Expect(len(resp.Data[0].Embedding)).To(Equal(768))
+		})
+	})
+
+	Describe("TTS APIs", func() {
+		Context("TTS", func() {
+			It("should generate mocked audio", func() {
+				req, err := http.NewRequest("POST", apiURL+"/audio/speech", nil)
+				Expect(err).ToNot(HaveOccurred())
+				req.Header.Set("Content-Type", "application/json")
+
+				body := `{"model":"mock-model","input":"Hello world","voice":"default"}`
+				req.Body = http.NoBody
+				req.GetBody = func() (io.ReadCloser, error) {
+					return io.NopCloser(strings.NewReader(body)), nil
+				}
+
+				// Use direct HTTP client for TTS endpoint
+				httpClient := &http.Client{Timeout: 30 * time.Second}
+				resp, err := httpClient.Do(req)
+				if err == nil {
+					defer resp.Body.Close()
+					Expect(resp.StatusCode).To(BeNumerically("<", 500))
+				}
+			})
+		})
+	})
+
+	Describe("Image Generation API", func() {
+		It("should generate mocked image", func() {
+			req, err := http.NewRequest("POST", apiURL+"/images/generations", nil)
+			Expect(err).ToNot(HaveOccurred())
+			req.Header.Set("Content-Type", "application/json")
+
+			body := `{"model":"mock-model","prompt":"a cat"}`
+			req.Body = http.NoBody
+			req.GetBody = func() (io.ReadCloser, error) {
+				return io.NopCloser(strings.NewReader(body)), nil
+			}
+
+			httpClient := &http.Client{Timeout: 30 * time.Second}
+			resp, err := httpClient.Do(req)
+			if err == nil {
+				defer resp.Body.Close()
+				Expect(resp.StatusCode).To(BeNumerically("<", 500))
+			}
+		})
+	})
+
+	Describe("Audio Transcription API", func() {
+		It("should return mocked transcription", func() {
+			req, err := http.NewRequest("POST", apiURL+"/audio/transcriptions", nil)
+			Expect(err).ToNot(HaveOccurred())
+			req.Header.Set("Content-Type", "multipart/form-data")
+
+			httpClient := &http.Client{Timeout: 30 * time.Second}
+			resp, err := httpClient.Do(req)
+			if err == nil {
+				defer resp.Body.Close()
+				Expect(resp.StatusCode).To(BeNumerically("<", 500))
+			}
+		})
+	})
+
+	Describe("Rerank API", func() {
+		It("should return mocked reranking results", func() {
+			req, err := http.NewRequest("POST", apiURL+"/rerank", nil)
+			Expect(err).ToNot(HaveOccurred())
+			req.Header.Set("Content-Type", "application/json")
+
+			body := `{"model":"mock-model","query":"test","documents":["doc1","doc2"]}`
+			req.Body = http.NoBody
+			req.GetBody = func() (io.ReadCloser, error) {
+				return io.NopCloser(strings.NewReader(body)), nil
+			}
+
+			httpClient := &http.Client{Timeout: 30 * time.Second}
+			resp, err := httpClient.Do(req)
+			if err == nil {
+				defer resp.Body.Close()
+				Expect(resp.StatusCode).To(BeNumerically("<", 500))
+			}
+		})
+	})
+
+	Describe("Tokenization API", func() {
+		It("should return mocked tokens", func() {
+			req, err := http.NewRequest("POST", apiURL+"/tokenize", nil)
+			Expect(err).ToNot(HaveOccurred())
+			req.Header.Set("Content-Type", "application/json")
+
+			body := `{"model":"mock-model","text":"Hello world"}`
+			req.Body = http.NoBody
+			req.GetBody = func() (io.ReadCloser, error) {
+				return io.NopCloser(strings.NewReader(body)), nil
+			}
+
+			httpClient := &http.Client{Timeout: 30 * time.Second}
+			resp, err := httpClient.Do(req)
+			if err == nil {
+				defer resp.Body.Close()
+				Expect(resp.StatusCode).To(BeNumerically("<", 500))
+			}
+		})
+	})
+})