diff --git a/.changeset/bold-towns-start.md b/.changeset/bold-towns-start.md
new file mode 100644
index 000000000..acf0b70c0
--- /dev/null
+++ b/.changeset/bold-towns-start.md
@@ -0,0 +1,5 @@
+---
+'@sap-ai-sdk/langchain': minor
+---
+
+[Compatibility Note] Remove structured ouput handling for deprecated gpt-4 & gpt-3 models
diff --git a/.changeset/curly-drinks-taste.md b/.changeset/curly-drinks-taste.md
new file mode 100644
index 000000000..02bdf2944
--- /dev/null
+++ b/.changeset/curly-drinks-taste.md
@@ -0,0 +1,6 @@
+---
+'@sap-ai-sdk/orchestration': minor
+'@sap-ai-sdk/core': minor
+---
+
+[Improvement] Add `cohere--command-a-reasoning`, `mistralai--mistral-medium-instruct` and perplexity-ai `sonar` and `sonar-pro` to model list
diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
index 0265b0176..f4f1fc54f 100644
--- a/packages/core/src/index.ts
+++ b/packages/core/src/index.ts
@@ -7,6 +7,7 @@ export type {
   AzureOpenAiEmbeddingModel,
   GcpVertexAiChatModel,
   AwsBedrockChatModel,
-  AiCoreOpenSourceChatModel
+  AiCoreOpenSourceChatModel,
+  PerplexityChatModel
 } from './model-types.js';
 export { SseStream, LineDecoder, SSEDecoder } from './stream/index.js';
diff --git a/packages/core/src/model-types.ts b/packages/core/src/model-types.ts
index ae99dbdf0..da2874552 100644
--- a/packages/core/src/model-types.ts
+++ b/packages/core/src/model-types.ts
@@ -52,9 +52,17 @@ export type AwsBedrockChatModel = LiteralUnion<
   | 'amazon--nova-premier'
 >;
 
+/**
+ * Perplexity models for chat completion.
+ */
+export type PerplexityChatModel = LiteralUnion<'sonar' | 'sonar-pro'>;
+
 /**
  * AI Core open source models for chat completion.
  */
 export type AiCoreOpenSourceChatModel = LiteralUnion<
-  'mistralai--mistral-large-instruct' | 'mistralai--mistral-small-instruct'
+  | 'cohere--command-a-reasoning'
+  | 'mistralai--mistral-large-instruct'
+  | 'mistralai--mistral-medium-instruct'
+  | 'mistralai--mistral-small-instruct'
 >;
diff --git a/packages/langchain/src/openai/chat.test.ts b/packages/langchain/src/openai/chat.test.ts
index 6772cb0bf..2014b4a7f 100644
--- a/packages/langchain/src/openai/chat.test.ts
+++ b/packages/langchain/src/openai/chat.test.ts
@@ -259,20 +259,6 @@ describe('Chat client', () => {
       );
     });
 
-    it('should use `functionCalling` for older deprecated models', async () => {
-      const oldClient = new AzureOpenAiChatClient({
-        modelName: 'gpt-35-turbo'
-      });
-      const spy = jest.spyOn(oldClient, 'withConfig');
-
-      oldClient.withStructuredOutput(joke);
-      expect(spy).toHaveBeenCalledWith(
-        expect.objectContaining({
-          tools: expect.any(Array)
-        })
-      );
-    });
-
     it('should use `functionCalling` with openai function json schema', async () => {
       const openAiFunctionJsonSchema: AzureOpenAiFunctionObject = {
         name: 'joke',
diff --git a/packages/langchain/src/openai/chat.ts b/packages/langchain/src/openai/chat.ts
index 2b7dbee4f..5413d6c80 100644
--- a/packages/langchain/src/openai/chat.ts
+++ b/packages/langchain/src/openai/chat.ts
@@ -175,18 +175,8 @@ export class AzureOpenAiChatClient extends BaseChatModel<AzureOpenAiChatCallOpti
       );
     }
 
-    // TODO: Remove this once the deprecated models are removed
-    if (
-      !this.modelName.startsWith('gpt-3') &&
-      !this.modelName.startsWith('gpt-4-') &&
-      this.modelName !== 'gpt-4'
-    ) {
-      if (method === undefined) {
-        method = 'jsonSchema';
-      }
-    } else if (method === 'jsonSchema') {
-      // Falling back to tool calling.`
-      method = '';
+    if (method === undefined) {
+      method = 'jsonSchema';
     }
 
     if (method === 'jsonMode') {
diff --git a/packages/orchestration/src/model-types.ts b/packages/orchestration/src/model-types.ts
index c8ad81a4e..10da5986a 100644
--- a/packages/orchestration/src/model-types.ts
+++ b/packages/orchestration/src/model-types.ts
@@ -2,7 +2,8 @@ import type {
   AiCoreOpenSourceChatModel,
   AwsBedrockChatModel,
   AzureOpenAiChatModel,
-  GcpVertexAiChatModel
+  GcpVertexAiChatModel,
+  PerplexityChatModel
 } from '@sap-ai-sdk/core';
 
 /**
@@ -12,4 +13,5 @@ export type ChatModel =
   | AzureOpenAiChatModel
   | GcpVertexAiChatModel
   | AwsBedrockChatModel
+  | PerplexityChatModel
   | AiCoreOpenSourceChatModel;