diff --git a/packages/gen-ai-hub/src/client/openai/openai-client.test.ts b/packages/gen-ai-hub/src/client/openai/openai-client.test.ts
index 3ebf2630..9b0284cb 100644
--- a/packages/gen-ai-hub/src/client/openai/openai-client.test.ts
+++ b/packages/gen-ai-hub/src/client/openai/openai-client.test.ts
@@ -1,14 +1,14 @@
-import fs from 'fs';
-import path from 'path';
 import nock from 'nock';
 import { HttpDestination } from '@sap-cloud-sdk/connectivity';
 import { mockGetAiCoreDestination } from '../../../test-util/mock-context.js';
 import {
-  BaseLlmParameters,
   BaseLlmParametersWithDeploymentId,
   EndpointOptions
 } from '../../core/http-client.js';
-import { mockInference } from '../../../test-util/mock-http.js';
+import {
+  mockInference,
+  parseMockResponse
+} from '../../../test-util/mock-http.js';
 import { OpenAiClient } from './openai-client.js';
 import {
   OpenAiChatCompletionOutput,
@@ -20,17 +20,15 @@ import {
 
 describe('openai client', () => {
   let destination: HttpDestination;
-  let deploymentConfig: BaseLlmParameters;
+  const deploymentConfiguration: BaseLlmParametersWithDeploymentId = {
+    deploymentId: 'deployment-id'
+  };
   let chatCompletionEndpoint: EndpointOptions;
   let embeddingsEndpoint: EndpointOptions;
 
   beforeAll(() => {
     destination = mockGetAiCoreDestination();
-    deploymentConfig = {
-      deploymentConfiguration: {
-        deploymentId: 'deployment-id'
-      } as BaseLlmParametersWithDeploymentId
-    };
+
     chatCompletionEndpoint = {
       url: 'chat/completions',
       apiVersion: '2024-02-01'
@@ -58,16 +56,11 @@ describe('openai client', () => {
       };
       const request: OpenAiChatCompletionParameters = {
         ...prompt,
-        ...deploymentConfig
+        deploymentConfiguration
       };
-      const mockResponse = fs.readFileSync(
-        path.join(
-          'test-util',
-          'mock-data',
-          'openai',
-          'openai-chat-completion-success-response.json'
-        ),
-        'utf8'
+      const mockResponse = parseMockResponse<OpenAiChatCompletionOutput>(
+        'openai',
+        'openai-chat-completion-success-response.json'
       );
 
       mockInference(
@@ -75,35 +68,27 @@ describe('openai client', () => {
           data: request
         },
         {
-          data: JSON.parse(mockResponse),
+          data: mockResponse,
           status: 200
         },
         destination,
         chatCompletionEndpoint
       );
 
-      const result: OpenAiChatCompletionOutput =
-        await new OpenAiClient().chatCompletion(request);
-      const expectedResponse: OpenAiChatCompletionOutput =
-        JSON.parse(mockResponse);
-
-      expect(result).toEqual(expectedResponse);
+      expect(new OpenAiClient().chatCompletion(request)).resolves.toEqual(
+        mockResponse
+      );
     });
 
     it('throws on bad request', async () => {
       const prompt = { messages: [] };
       const request: OpenAiChatCompletionParameters = {
         ...prompt,
-        ...deploymentConfig
+        deploymentConfiguration
       };
-      const mockResponse = fs.readFileSync(
-        path.join(
-          'test-util',
-          'mock-data',
-          'openai',
-          'openai-error-response.json'
-        ),
-        'utf8'
+      const mockResponse = parseMockResponse(
+        'openai',
+        'openai-error-response.json'
       );
 
       mockInference(
@@ -111,7 +96,7 @@ describe('openai client', () => {
           data: request
         },
         {
-          data: JSON.parse(mockResponse),
+          data: mockResponse,
           status: 400
         },
         destination,
@@ -129,16 +114,11 @@ describe('openai client', () => {
       const prompt = { input: ['AI is fascinating'] };
       const request: OpenAiEmbeddingParameters = {
         ...prompt,
-        ...deploymentConfig
+        deploymentConfiguration
       };
-      const mockResponse = fs.readFileSync(
-        path.join(
-          'test-util',
-          'mock-data',
-          'openai',
-          'openai-embeddings-success-response.json'
-        ),
-        'utf8'
+      const mockResponse = parseMockResponse<OpenAiEmbeddingOutput>(
+        'openai',
+        'openai-embeddings-success-response.json'
       );
 
       mockInference(
@@ -146,34 +126,27 @@ describe('openai client', () => {
           data: request
         },
         {
-          data: JSON.parse(mockResponse),
+          data: mockResponse,
           status: 200
         },
         destination,
         embeddingsEndpoint
       );
 
-      const result: OpenAiEmbeddingOutput = await new OpenAiClient().embeddings(
-        request
+      expect(new OpenAiClient().embeddings(request)).resolves.toEqual(
+        mockResponse
       );
-      const expectedResponse: OpenAiEmbeddingOutput = JSON.parse(mockResponse);
-      expect(result).toEqual(expectedResponse);
     });
 
     it('throws on bad request', async () => {
       const prompt = { input: [] };
       const request: OpenAiEmbeddingParameters = {
         ...prompt,
-        ...deploymentConfig
+        deploymentConfiguration
       };
-      const mockResponse = fs.readFileSync(
-        path.join(
-          'test-util',
-          'mock-data',
-          'openai',
-          'openai-error-response.json'
-        ),
-        'utf8'
+      const mockResponse = parseMockResponse(
+        'openai',
+        'openai-error-response.json'
       );
 
       mockInference(
@@ -181,14 +154,14 @@ describe('openai client', () => {
           data: request
         },
         {
-          data: JSON.parse(mockResponse),
+          data: mockResponse,
           status: 400
         },
         destination,
         embeddingsEndpoint
       );
 
-      await expect(new OpenAiClient().embeddings(request)).rejects.toThrow();
+      expect(new OpenAiClient().embeddings(request)).rejects.toThrow();
     });
   });
 });
diff --git a/packages/gen-ai-hub/src/orchestration/api/schema/chat-message.ts b/packages/gen-ai-hub/src/orchestration/api/schema/chat-message.ts
index 7c442063..ea30476f 100644
--- a/packages/gen-ai-hub/src/orchestration/api/schema/chat-message.ts
+++ b/packages/gen-ai-hub/src/orchestration/api/schema/chat-message.ts
@@ -8,6 +8,6 @@
  * Representation of the 'ChatMessage' schema.
  */
 export type ChatMessage = {
-  role: string;
+  role: 'user' | 'assistant' | 'system';
   content: string;
 } & Record<string, any>;
diff --git a/packages/gen-ai-hub/src/orchestration/orchestration-client.test.ts b/packages/gen-ai-hub/src/orchestration/orchestration-client.test.ts
index 7be29d2b..1b1131b3 100644
--- a/packages/gen-ai-hub/src/orchestration/orchestration-client.test.ts
+++ b/packages/gen-ai-hub/src/orchestration/orchestration-client.test.ts
@@ -1,25 +1,33 @@
-import fs from 'fs';
-import path from 'path';
 import nock from 'nock';
 import { HttpDestination } from '@sap-cloud-sdk/connectivity';
-import { BaseLlmParametersWithDeploymentId } from '../core/index.js';
 import { mockGetAiCoreDestination } from '../../test-util/mock-context.js';
-import { mockInference } from '../../test-util/mock-http.js';
+import { mockInference, parseMockResponse } from '../../test-util/mock-http.js';
+import { BaseLlmParametersWithDeploymentId } from '../core/index.js';
 import {
   GenAiHubClient,
   GenAiHubCompletionParameters
 } from './orchestration-client.js';
-import { CompletionPostResponse, ModuleConfigs } from './api/index.js';
+import {
+  CompletionPostResponse,
+  LLMModuleConfig,
+  ModuleConfigs
+} from './api/index.js';
 
 describe('GenAiHubClient', () => {
   let destination: HttpDestination;
-  let deploymentConfiguration: BaseLlmParametersWithDeploymentId;
   let client: GenAiHubClient;
+  const deploymentConfiguration: BaseLlmParametersWithDeploymentId = {
+    deploymentId: 'deployment-id'
+  };
+  const llm_module_config: LLMModuleConfig = {
+    model_name: 'gpt-35-turbo-16k',
+    model_params: {
+      max_tokens: 50,
+      temperature: 0.1
+    }
+  };
 
   beforeAll(() => {
-    deploymentConfiguration = {
-      deploymentId: 'deployment-id'
-    };
     destination = mockGetAiCoreDestination();
     client = new GenAiHubClient();
   });
@@ -28,32 +36,21 @@ describe('GenAiHubClient', () => {
     nock.cleanAll();
   });
 
-  it(' calls chatCompletion and parses response', async () => {
+  it('calls chatCompletion with minimum configuration and parses response', async () => {
     const module_configurations: ModuleConfigs = {
       templating_module_config: {
         template: [{ role: 'user', content: 'Hello!' }]
       },
-      llm_module_config: {
-        model_name: 'gpt-35-turbo-16k',
-        model_params: {
-          max_tokens: 50,
-          temperature: 0.1
-        }
-      }
+      llm_module_config
     };
     const request: GenAiHubCompletionParameters = {
       deploymentConfiguration,
       orchestration_config: { module_configurations }
     };
 
-    const mockResponse = fs.readFileSync(
-      path.join(
-        'test-util',
-        'mock-data',
-        'orchestration',
-        'genaihub-chat-completion-success-response.json'
-      ),
-      'utf-8'
+    const mockResponse = parseMockResponse<CompletionPostResponse>(
+      'orchestration',
+      'genaihub-chat-completion-success-response.json'
     );
 
     mockInference(
@@ -61,7 +58,7 @@ describe('GenAiHubClient', () => {
         data: { ...request, input_params: {} }
       },
       {
-        data: JSON.parse(mockResponse),
+        data: mockResponse,
         status: 200
       },
       destination,
@@ -69,51 +66,55 @@ describe('GenAiHubClient', () => {
         url: 'completion'
       }
     );
-    const result = await client.chatCompletion(request);
-    const expectedResponse: CompletionPostResponse = JSON.parse(mockResponse);
-    expect(result).toEqual(expectedResponse);
+    expect(client.chatCompletion(request)).resolves.toEqual(mockResponse);
   });
 
-  it('throws error for incorrect input parameters', async () => {
+  it('sends message history together with templating config', async () => {
     const module_configurations: ModuleConfigs = {
       templating_module_config: {
-        template: [{ role: 'actor', content: 'Hello' }]
+        template: [{ role: 'user', content: "What's my name?" }]
       },
-      llm_module_config: {
-        model_name: 'gpt-35-turbo-16k',
-        model_params: {
-          max_tokens: 50,
-          temperature: 0.1
-        }
-      }
+      llm_module_config
     };
     const request: GenAiHubCompletionParameters = {
       deploymentConfiguration,
-      orchestration_config: { module_configurations }
+      orchestration_config: { module_configurations },
+      messages_history: [
+        {
+          role: 'system',
+          content:
+            'You are a helpful assistant who remembers all details the user shares with you.'
+        },
+        {
+          role: 'user',
+          content: 'Hi! Im Bob'
+        },
+        {
+          role: 'assistant',
+          content:
+            "Hi Bob, nice to meet you! I'm an AI assistant. I'll remember that your name is Bob as we continue our conversation."
+        }
+      ]
     };
-    const mockResponse = fs.readFileSync(
-      path.join(
-        'test-util',
-        'mock-data',
-        'orchestration',
-        'genaihub-error-response.json'
-      ),
-      'utf-8'
-    );
 
+    const mockResponse = parseMockResponse<CompletionPostResponse>(
+      'orchestration',
+      'genaihub-chat-completion-message-history.json'
+    );
     mockInference(
       {
         data: { ...request, input_params: {} }
       },
       {
-        data: JSON.parse(mockResponse),
-        status: 400
+        data: mockResponse,
+        status: 200
       },
       destination,
       {
         url: 'completion'
       }
     );
-    await expect(client.chatCompletion(request)).rejects.toThrow();
+
+    expect(client.chatCompletion(request)).resolves.toEqual(mockResponse);
   });
 });
diff --git a/packages/gen-ai-hub/src/orchestration/orchestration-client.ts b/packages/gen-ai-hub/src/orchestration/orchestration-client.ts
index fc730c1d..d09b9090 100644
--- a/packages/gen-ai-hub/src/orchestration/orchestration-client.ts
+++ b/packages/gen-ai-hub/src/orchestration/orchestration-client.ts
@@ -12,7 +12,7 @@ import {
  * Input Parameters for GenAI hub chat completion.
  */
 export type GenAiHubCompletionParameters = BaseLlmParameters &
-  Pick<CompletionPostRequest, 'orchestration_config'>;
+  Pick<CompletionPostRequest, 'orchestration_config' | 'messages_history'>;
 
 /**
  * Get the orchestration client.
diff --git a/packages/gen-ai-hub/test-util/mock-data/orchestration/genaihub-chat-completion-message-history.json b/packages/gen-ai-hub/test-util/mock-data/orchestration/genaihub-chat-completion-message-history.json
new file mode 100644
index 00000000..1e7d45fb
--- /dev/null
+++ b/packages/gen-ai-hub/test-util/mock-data/orchestration/genaihub-chat-completion-message-history.json
@@ -0,0 +1,65 @@
+{
+  "module_results": {
+    "llm": {
+      "choices": [
+        {
+          "finish_reason": "stop",
+          "index": 0,
+          "message": {
+            "content": "Your name is Bob.",
+            "role": "assistant"
+          }
+        }
+      ],
+      "created": 1721229750,
+      "id": "chatcmpl-9m0m6iwV6nY8IsW6jY622P6xISg3q",
+      "model": "gpt-35-turbo-16k",
+      "object": "chat.completion",
+      "usage": {
+        "completion_tokens": 5,
+        "prompt_tokens": 71,
+        "total_tokens": 76
+      }
+    },
+    "templating": [
+      {
+        "content": "You are a helpful assistant who remembers all details the user shares with you.",
+        "role": "system"
+      },
+      {
+        "content": "Hi! Im Bob",
+        "role": "user"
+      },
+      {
+        "content": "Hi Bob, nice to meet you! I'm an AI assistant. I'll remember that your name is Bob as we continue our conversation.",
+        "role": "assistant"
+      },
+      {
+        "content": "What's my name?",
+        "role": "user"
+      }
+    ]
+  },
+  "orchestration_result": {
+    "choices": [
+      {
+        "finish_reason": "stop",
+        "index": 0,
+        "message": {
+          "content": "Your name is Bob.",
+          "role": "assistant"
+        }
+      }
+    ],
+    "created": 1721229750,
+    "id": "chatcmpl-9m0m6iwV6nY8IsW6jY622P6xISg3q",
+    "model": "gpt-35-turbo-16k",
+    "object": "chat.completion",
+    "usage": {
+      "completion_tokens": 5,
+      "prompt_tokens": 71,
+      "total_tokens": 76
+    }
+  },
+  "request_id": "841b6d08-733c-47d4-bf9f-0c948e25cf01"
+}
diff --git a/packages/gen-ai-hub/test-util/mock-data/orchestration/genaihub-error-response.json b/packages/gen-ai-hub/test-util/mock-data/orchestration/genaihub-error-response.json
deleted file mode 100644
index 2e5416f1..00000000
--- a/packages/gen-ai-hub/test-util/mock-data/orchestration/genaihub-error-response.json
+++ /dev/null
@@ -1,14 +0,0 @@
-{
-  "request_id": "request-id",
-  "code": 400,
-  "message": "[] should be non-empty - 'messages'",
-  "location": "OpenAIClient",
-  "module_results": {
-    "templating": [
-      {
-        "role": "actor",
-        "content": "Hello"
-      }
-    ]
-  }
-}
diff --git a/packages/gen-ai-hub/test-util/mock-http.ts b/packages/gen-ai-hub/test-util/mock-http.ts
index 57cbc392..917ac6c2 100644
--- a/packages/gen-ai-hub/test-util/mock-http.ts
+++ b/packages/gen-ai-hub/test-util/mock-http.ts
@@ -1,3 +1,5 @@
+import fs from 'fs';
+import path from 'path';
 import { HttpDestination } from '@sap-cloud-sdk/connectivity';
 import nock from 'nock';
 import {
@@ -19,7 +21,6 @@ export function mockInference<D extends BaseLlmParameters>(
   response: {
     data: any;
     status?: number;
-    headers?: Record<string, string>;
   },
   destination: HttpDestination,
   endpoint: EndpointOptions = mockEndpoint
@@ -40,3 +41,12 @@ export function mockInference<D extends BaseLlmParameters>(
     .query(apiVersion ? { 'api-version': apiVersion } : {})
     .reply(response.status, response.data);
 }
+
+export function parseMockResponse<T>(client: string, fileName: string): T {
+  const fileContent = fs.readFileSync(
+    path.join('test-util', 'mock-data', client, fileName),
+    'utf-8'
+  );
+
+  return JSON.parse(fileContent);
+}
diff --git a/type-tests/orchestration.test-d.ts b/type-tests/orchestration.test-d.ts
index f8015043..5de0d6fc 100644
--- a/type-tests/orchestration.test-d.ts
+++ b/type-tests/orchestration.test-d.ts
@@ -122,3 +122,22 @@ expectError<any>(
     }
   })
 );
+
+expectError<any>(
+  client.chatCompletion({
+    deploymentConfiguration: { deploymentId: 'id' },
+    orchestration_config: {
+      module_configurations: {
+        templating_module_config: {
+          template: [{ role: 'test', content: 'some content' }]
+        },
+        llm_module_config: {
+          model_name: 'gpt-35-turbo-16k',
+          model_params: {
+            max_tokens: 50
+          }
+        }
+      }
+    }
+  })
+);