diff --git a/README.md b/README.md
index 0f13e67..8b8c40a 100644
--- a/README.md
+++ b/README.md
@@ -432,6 +432,251 @@ echo($d->choices[0]->message->content);
 
 > ### Related: [ChatGPT Clone Project](#chatgpt-clone-project)
 
+## Responses
+
+The Responses API (`POST /v1/responses`) is OpenAI's recommended replacement for Chat Completions. It accepts a flexible
+`input` (string or message array) plus an optional `instructions` system prompt, supports stateful multi-turn via
+`previous_response_id`, exposes built-in tools (`web_search`, `file_search`, `code_interpreter`, etc.), and returns a
+typed `output[]` array instead of `choices[]`.
+
+### Create response
+
+```php
+$result = $open_ai->response([
+    'model' => 'gpt-4o-mini',
+    'input' => 'Tell me a three sentence bedtime story about a unicorn.',
+]);
+```
+
+With an `instructions` system prompt and structured input:
+
+```php
+$result = $open_ai->response([
+    'model' => 'gpt-4o-mini',
+    'instructions' => 'You are a terse assistant.',
+    'input' => [
+        ['role' => 'user', 'content' => 'What is the capital of France?'],
+    ],
+]);
+```
+
+### Multi-turn with `previous_response_id`
+
+Instead of resending the full message history, pass the previous response's `id`:
+
+```php
+$first = $open_ai->response([
+    'model' => 'gpt-4o-mini',
+    'input' => 'My name is Joacir.',
+    'store' => true,
+]);
+$firstId = json_decode($first, true)['id'];
+
+$second = $open_ai->response([
+    'model' => 'gpt-4o-mini',
+    'previous_response_id' => $firstId,
+    'input' => 'What is my name?',
+]);
+```
+
+### Stream response
+
+Streaming uses Server-Sent Events. Pass `stream => true` plus a write callback, just like `chat()` / `completion()`:
+
+```php
+$opts = [
+    'model' => 'gpt-4o-mini',
+    'input' => 'Tell me a short story.',
+    'stream' => true,
+];
+
+header('Content-type: text/event-stream');
+header('Cache-Control: no-cache');
+
+$open_ai->response($opts, function ($curl_info, $data) {
+    echo $data;
+    ob_flush();
+    flush();
+
+    return strlen($data);
+});
+```
+
+### Retrieve response
+
+```php
+$result = $open_ai->retrieveResponse('resp_abc123');
+```
+
+### Delete response
+
+```php
+$result = $open_ai->deleteResponse('resp_abc123');
+```
+
+### Cancel response
+
+Cancels a response created with `background => true` that has not finished yet.
+
+```php
+$result = $open_ai->cancelResponse('resp_abc123');
+```
+
+### List response input items
+
+Returns the input items for a stored response. Accepts paging query params (`limit`, `order`, `after`, `before`,
+`include`).
+
+```php
+$result = $open_ai->listResponseInputItems('resp_abc123', ['limit' => 20]);
+```
+
+### Migrating from `chat()` to `response()`
+
+| Chat Completions                       | Responses                                         |
+|----------------------------------------|---------------------------------------------------|
+| `messages` array with `system`/`user`  | `input` (string or array) + `instructions`        |
+| `response_format`                      | `text.format`                                     |
+| `choices[0].message.content`           | `output[].content[].text` (or SDK `output_text`)  |
+| Manual conversation history            | `previous_response_id` for stateful chaining      |
+| Custom tool plumbing                   | Built-in tools via `tools` (web_search, etc.)     |
+
+## Conversations
+
+The Conversations API replaces Assistants Threads for stateful multi-turn. A conversation stores `items` (messages, tool
+calls, tool outputs, reasoning items). Reference a conversation from `response()` via `$opts['conversation']` and the
+model has the full history without you resending it.
+
+### Create conversation
+
+```php
+$conv = $open_ai->createConversation([
+    'metadata' => ['user_id' => '42'],
+    'items' => [
+        ['type' => 'message', 'role' => 'user', 'content' => 'Remember my name is Joacir.'],
+    ],
+]);
+$convId = json_decode($conv, true)['id'];
+```
+
+### Use a conversation with `response()`
+
+```php
+$result = $open_ai->response([
+    'model' => 'gpt-4o-mini',
+    'conversation' => $convId,
+    'input' => 'What is my name?',
+]);
+```
+
+### Retrieve, modify, delete conversation
+
+```php
+$open_ai->retrieveConversation($convId);
+$open_ai->modifyConversation($convId, ['metadata' => ['status' => 'closed']]);
+$open_ai->deleteConversation($convId);
+```
+
+### Items (messages, tool calls, tool outputs)
+
+```php
+$open_ai->createConversationItems($convId, [
+    'items' => [
+        ['type' => 'message', 'role' => 'user', 'content' => 'New question.'],
+    ],
+]);
+
+$open_ai->listConversationItems($convId, ['limit' => 20, 'order' => 'desc']);
+$open_ai->retrieveConversationItem($convId, 'item_abc123');
+$open_ai->deleteConversationItem($convId, 'item_abc123');
+```
+
+## Vector Stores
+
+Vector stores power the `file_search` tool in Responses. Upload files via `uploadFile()` first, then attach them to a
+vector store.
+
+### Create, list, retrieve, modify, delete
+
+```php
+$vs = $open_ai->createVectorStore([
+    'name' => 'support-docs',
+    'expires_after' => ['anchor' => 'last_active_at', 'days' => 7],
+]);
+$vsId = json_decode($vs, true)['id'];
+
+$open_ai->listVectorStores(['limit' => 20]);
+$open_ai->retrieveVectorStore($vsId);
+$open_ai->modifyVectorStore($vsId, ['name' => 'kb-v2']);
+$open_ai->deleteVectorStore($vsId);
+```
+
+### Search a vector store directly
+
+```php
+$open_ai->searchVectorStore($vsId, [
+    'query' => 'refund policy',
+    'max_num_results' => 5,
+]);
+```
+
+### Files in a vector store
+
+```php
+$open_ai->createVectorStoreFile($vsId, ['file_id' => 'file-abc']);
+$open_ai->listVectorStoreFiles($vsId, ['limit' => 50]);
+$open_ai->retrieveVectorStoreFile($vsId, 'file-abc');
+$open_ai->updateVectorStoreFileAttributes($vsId, 'file-abc', [
+    'attributes' => ['language' => 'pt-BR'],
+]);
+$open_ai->deleteVectorStoreFile($vsId, 'file-abc');
+$open_ai->retrieveVectorStoreFileContent($vsId, 'file-abc');
+```
+
+### File batches
+
+Bulk attach files in one async job:
+
+```php
+$batch = $open_ai->createVectorStoreFileBatch($vsId, [
+    'file_ids' => ['file-a', 'file-b', 'file-c'],
+]);
+$batchId = json_decode($batch, true)['id'];
+
+$open_ai->retrieveVectorStoreFileBatch($vsId, $batchId);
+$open_ai->listVectorStoreFileBatchFiles($vsId, $batchId, ['limit' => 100]);
+$open_ai->cancelVectorStoreFileBatch($vsId, $batchId);
+```
+
+### Use vector store with `response()` and `file_search`
+
+```php
+$open_ai->response([
+    'model' => 'gpt-4o-mini',
+    'input' => 'What is the refund policy?',
+    'tools' => [
+        ['type' => 'file_search', 'vector_store_ids' => [$vsId]],
+    ],
+]);
+```
+
+## Prompts
+
+Retrieve a Prompt template created in the OpenAI dashboard:
+
+```php
+$open_ai->retrievePrompt('pmpt_abc123');
+```
+
+Then reference it from `response()`:
+
+```php
+$open_ai->response([
+    'model' => 'gpt-4o-mini',
+    'prompt' => ['id' => 'pmpt_abc123', 'variables' => ['city' => 'São Paulo']],
+]);
+```
+
 ## Completions
 
 Given a prompt, the model will return one or more predicted completions, and can also return the probabilities of
@@ -931,6 +1176,24 @@ $result = $open_ai->retrieveModel("text-ada-001");
  ```php
 echo $search;
 ```
+## ⚠️ Assistants Beta API — Deprecation Notice
+
+The Assistants beta family below (**Assistants**, **Threads**, **Messages**, **Runs**) is being shut down by OpenAI
+on **August 26, 2026**. Migrate to the new stack:
+
+| Legacy (Assistants beta)        | New (GA)                                            |
+|---------------------------------|-----------------------------------------------------|
+| `createAssistant()`             | Build prompts in the dashboard + pass via `prompt`  |
+| `createThread()`                | `createConversation()`                              |
+| `createThreadMessage()`         | `createConversationItems()`                         |
+| `listThreadMessages()`          | `listConversationItems()`                           |
+| `createRun()`                   | `response()` with `'conversation' => $convId`       |
+| `retrieveRunStep()`             | Inspect `response.output[]` (steps are items)       |
+| `submitToolOutputs()`           | App code manages tool loops between `response()` calls |
+| Assistant Files / Message Files | `createVectorStoreFile()` + `file_search` tool      |
+
+All legacy methods are annotated `@deprecated` and will be removed in a future major release.
+
 ## Assistants (beta)
 
 Allows you to build AI assistants within your own applications.
diff --git a/src/OpenAi.php b/src/OpenAi.php
index 87bfcbe..0f34e10 100644
--- a/src/OpenAi.php
+++ b/src/OpenAi.php
@@ -213,8 +213,8 @@ public function moderation($opts)
      */
     public function chat($opts, $stream = null)
     {
-        if ($stream != null && array_key_exists('stream', $opts)) {
-            if (! $opts['stream']) {
+        if (array_key_exists('stream', $opts) && $opts['stream']) {
+            if ($stream == null) {
                 throw new Exception(
                     'Please provide a stream function. Check https://github.com/orhanerday/open-ai#stream-example for an example.'
                 );
@@ -230,6 +230,416 @@ public function chat($opts, $stream = null)
         return $this->sendRequest($url, 'POST', $opts);
     }
 
+    /**
+     * @param        $opts
+     * @param  null  $stream
+     * @return bool|string
+     * @throws Exception
+     */
+    public function response($opts, $stream = null)
+    {
+        if (array_key_exists('stream', $opts) && $opts['stream']) {
+            if ($stream == null) {
+                throw new Exception(
+                    'Please provide a stream function. Check https://github.com/orhanerday/open-ai#stream-example for an example.'
+                );
+            }
+
+            $this->stream_method = $stream;
+        }
+
+        $url = Url::responsesUrl();
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST', $opts);
+    }
+
+    /**
+     * @param $response_id
+     * @return bool|string
+     */
+    public function retrieveResponse($response_id)
+    {
+        $response_id = "/$response_id";
+        $url = Url::responsesUrl().$response_id;
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param $response_id
+     * @return bool|string
+     */
+    public function deleteResponse($response_id)
+    {
+        $response_id = "/$response_id";
+        $url = Url::responsesUrl().$response_id;
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'DELETE');
+    }
+
+    /**
+     * @param $response_id
+     * @return bool|string
+     */
+    public function cancelResponse($response_id)
+    {
+        $response_id = "/$response_id/cancel";
+        $url = Url::responsesUrl().$response_id;
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST');
+    }
+
+    /**
+     * @param        $response_id
+     * @param  array $query
+     * @return bool|string
+     */
+    public function listResponseInputItems($response_id, $query = [])
+    {
+        $url = Url::responsesUrl()."/$response_id/input_items";
+        if (! empty($query)) {
+            $url .= '?'.http_build_query($query);
+        }
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param  array $data
+     * @return bool|string
+     */
+    public function createConversation($data = [])
+    {
+        $url = Url::conversationsUrl();
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST', $data);
+    }
+
+    /**
+     * @param $conversation_id
+     * @return bool|string
+     */
+    public function retrieveConversation($conversation_id)
+    {
+        $url = Url::conversationsUrl()."/$conversation_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param        $conversation_id
+     * @param  array $data
+     * @return bool|string
+     */
+    public function modifyConversation($conversation_id, $data)
+    {
+        $url = Url::conversationsUrl()."/$conversation_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST', $data);
+    }
+
+    /**
+     * @param $conversation_id
+     * @return bool|string
+     */
+    public function deleteConversation($conversation_id)
+    {
+        $url = Url::conversationsUrl()."/$conversation_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'DELETE');
+    }
+
+    /**
+     * @param        $conversation_id
+     * @param  array $data
+     * @return bool|string
+     */
+    public function createConversationItems($conversation_id, $data)
+    {
+        $url = Url::conversationsUrl()."/$conversation_id/items";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST', $data);
+    }
+
+    /**
+     * @param        $conversation_id
+     * @param  array $query
+     * @return bool|string
+     */
+    public function listConversationItems($conversation_id, $query = [])
+    {
+        $url = Url::conversationsUrl()."/$conversation_id/items";
+        if (! empty($query)) {
+            $url .= '?'.http_build_query($query);
+        }
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param $conversation_id
+     * @param $item_id
+     * @return bool|string
+     */
+    public function retrieveConversationItem($conversation_id, $item_id)
+    {
+        $url = Url::conversationsUrl()."/$conversation_id/items/$item_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param $conversation_id
+     * @param $item_id
+     * @return bool|string
+     */
+    public function deleteConversationItem($conversation_id, $item_id)
+    {
+        $url = Url::conversationsUrl()."/$conversation_id/items/$item_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'DELETE');
+    }
+
+    /**
+     * @param  array $data
+     * @return bool|string
+     */
+    public function createVectorStore($data = [])
+    {
+        $url = Url::vectorStoresUrl();
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST', $data);
+    }
+
+    /**
+     * @param  array $query
+     * @return bool|string
+     */
+    public function listVectorStores($query = [])
+    {
+        $url = Url::vectorStoresUrl();
+        if (! empty($query)) {
+            $url .= '?'.http_build_query($query);
+        }
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param $vector_store_id
+     * @return bool|string
+     */
+    public function retrieveVectorStore($vector_store_id)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param        $vector_store_id
+     * @param  array $data
+     * @return bool|string
+     */
+    public function modifyVectorStore($vector_store_id, $data)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST', $data);
+    }
+
+    /**
+     * @param $vector_store_id
+     * @return bool|string
+     */
+    public function deleteVectorStore($vector_store_id)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'DELETE');
+    }
+
+    /**
+     * @param        $vector_store_id
+     * @param  array $data
+     * @return bool|string
+     */
+    public function searchVectorStore($vector_store_id, $data)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/search";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST', $data);
+    }
+
+    /**
+     * @param        $vector_store_id
+     * @param  array $data
+     * @return bool|string
+     */
+    public function createVectorStoreFile($vector_store_id, $data)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/files";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST', $data);
+    }
+
+    /**
+     * @param        $vector_store_id
+     * @param  array $query
+     * @return bool|string
+     */
+    public function listVectorStoreFiles($vector_store_id, $query = [])
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/files";
+        if (! empty($query)) {
+            $url .= '?'.http_build_query($query);
+        }
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param $vector_store_id
+     * @param $file_id
+     * @return bool|string
+     */
+    public function retrieveVectorStoreFile($vector_store_id, $file_id)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/files/$file_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param        $vector_store_id
+     * @param        $file_id
+     * @param  array $data
+     * @return bool|string
+     */
+    public function updateVectorStoreFileAttributes($vector_store_id, $file_id, $data)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/files/$file_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST', $data);
+    }
+
+    /**
+     * @param $vector_store_id
+     * @param $file_id
+     * @return bool|string
+     */
+    public function deleteVectorStoreFile($vector_store_id, $file_id)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/files/$file_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'DELETE');
+    }
+
+    /**
+     * @param $vector_store_id
+     * @param $file_id
+     * @return bool|string
+     */
+    public function retrieveVectorStoreFileContent($vector_store_id, $file_id)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/files/$file_id/content";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param        $vector_store_id
+     * @param  array $data
+     * @return bool|string
+     */
+    public function createVectorStoreFileBatch($vector_store_id, $data)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/file_batches";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST', $data);
+    }
+
+    /**
+     * @param $vector_store_id
+     * @param $batch_id
+     * @return bool|string
+     */
+    public function retrieveVectorStoreFileBatch($vector_store_id, $batch_id)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/file_batches/$batch_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param $vector_store_id
+     * @param $batch_id
+     * @return bool|string
+     */
+    public function cancelVectorStoreFileBatch($vector_store_id, $batch_id)
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/file_batches/$batch_id/cancel";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'POST');
+    }
+
+    /**
+     * @param        $vector_store_id
+     * @param        $batch_id
+     * @param  array $query
+     * @return bool|string
+     */
+    public function listVectorStoreFileBatchFiles($vector_store_id, $batch_id, $query = [])
+    {
+        $url = Url::vectorStoresUrl()."/$vector_store_id/file_batches/$batch_id/files";
+        if (! empty($query)) {
+            $url .= '?'.http_build_query($query);
+        }
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
+    /**
+     * @param $prompt_id
+     * @return bool|string
+     */
+    public function retrievePrompt($prompt_id)
+    {
+        $url = Url::promptsUrl()."/$prompt_id";
+        $this->baseUrl($url);
+
+        return $this->sendRequest($url, 'GET');
+    }
+
     /**
      * @param $opts
      * @return bool|string
@@ -432,6 +842,7 @@ public function embeddings($opts)
     /**
      * @param array $data
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response()) and Conversations API.
      */
     public function createAssistant($data)
     {
@@ -446,6 +857,7 @@ public function createAssistant($data)
     /**
      * @param string $assistantId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response()) and Conversations API.
      */
     public function retrieveAssistant($assistantId)
     {
@@ -460,6 +872,7 @@ public function retrieveAssistant($assistantId)
      * @param string $assistantId
      * @param array $data
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response()) and Conversations API.
      */
     public function modifyAssistant($assistantId, $data)
     {
@@ -473,6 +886,7 @@ public function modifyAssistant($assistantId, $data)
     /**
      * @param string $assistantId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response()) and Conversations API.
      */
     public function deleteAssistant($assistantId)
     {
@@ -486,6 +900,7 @@ public function deleteAssistant($assistantId)
     /**
      * @param array $query
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response()) and Conversations API.
      */
     public function listAssistants($query = [])
     {
@@ -503,6 +918,7 @@ public function listAssistants($query = [])
      * @param string $assistantId
      * @param string $fileId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response()) and Conversations API.
      */
     public function createAssistantFile($assistantId, $fileId)
     {
@@ -517,6 +933,7 @@ public function createAssistantFile($assistantId, $fileId)
      * @param string $assistantId
      * @param string $fileId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response()) and Conversations API.
      */
     public function retrieveAssistantFile($assistantId, $fileId)
     {
@@ -531,6 +948,7 @@ public function retrieveAssistantFile($assistantId, $fileId)
      * @param string $assistantId
      * @param array $query
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response()) and Conversations API.
      */
     public function listAssistantFiles($assistantId, $query = [])
     {
@@ -548,6 +966,7 @@ public function listAssistantFiles($assistantId, $query = [])
      * @param string $assistantId
      * @param string $fileId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response()) and Conversations API.
      */
     public function deleteAssistantFile($assistantId, $fileId)
     {
@@ -561,6 +980,7 @@ public function deleteAssistantFile($assistantId, $fileId)
     /**
      * @param array $data
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Conversations API (createConversation()).
      */
     public function createThread($data = [])
     {
@@ -574,6 +994,7 @@ public function createThread($data = [])
     /**
      * @param string $threadId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Conversations API (retrieveConversation()).
      */
     public function retrieveThread($threadId)
     {
@@ -588,6 +1009,7 @@ public function retrieveThread($threadId)
      * @param string $threadId
      * @param array $data
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Conversations API (modifyConversation()).
      */
     public function modifyThread($threadId, $data)
     {
@@ -601,6 +1023,7 @@ public function modifyThread($threadId, $data)
     /**
      * @param string $threadId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Conversations API (deleteConversation()).
      */
     public function deleteThread($threadId)
     {
@@ -615,6 +1038,7 @@ public function deleteThread($threadId)
      * @param string $threadId
      * @param array $data
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Conversations API (createConversationItems()).
      */
     public function createThreadMessage($threadId, $data)
     {
@@ -629,6 +1053,7 @@ public function createThreadMessage($threadId, $data)
      * @param string $threadId
      * @param string $messageId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Conversations API (retrieveConversationItem()).
      */
     public function retrieveThreadMessage($threadId, $messageId)
     {
@@ -644,6 +1069,7 @@ public function retrieveThreadMessage($threadId, $messageId)
      * @param string $messageId
      * @param array $data
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Conversations API.
      */
     public function modifyThreadMessage($threadId, $messageId, $data)
     {
@@ -658,6 +1084,7 @@ public function modifyThreadMessage($threadId, $messageId, $data)
      * @param string $threadId
      * @param array $query
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Conversations API (listConversationItems()).
      */
     public function listThreadMessages($threadId, $query = [])
     {
@@ -676,6 +1103,7 @@ public function listThreadMessages($threadId, $query = [])
      * @param string $messageId
      * @param string $fileId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses/Conversations API.
      */
     public function retrieveMessageFile($threadId, $messageId, $fileId)
     {
@@ -691,6 +1119,7 @@ public function retrieveMessageFile($threadId, $messageId, $fileId)
      * @param string $messageId
      * @param array $query
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses/Conversations API.
      */
     public function listMessageFiles($threadId, $messageId, $query = [])
     {
@@ -708,6 +1137,7 @@ public function listMessageFiles($threadId, $messageId, $query = [])
      * @param string $threadId
      * @param array $data
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response() with conversation reference).
      */
     public function createRun($threadId, $data, $stream = null)
     {
@@ -732,6 +1162,7 @@ public function createRun($threadId, $data, $stream = null)
      * @param string $threadId
      * @param string $runId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (retrieveResponse()).
      */
     public function retrieveRun($threadId, $runId)
     {
@@ -747,6 +1178,7 @@ public function retrieveRun($threadId, $runId)
      * @param string $runId
      * @param array $data
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API.
      */
     public function modifyRun($threadId, $runId, $data)
     {
@@ -761,6 +1193,7 @@ public function modifyRun($threadId, $runId, $data)
      * @param string $threadId
      * @param array $query
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API.
      */
     public function listRuns($threadId, $query = [])
     {
@@ -779,6 +1212,7 @@ public function listRuns($threadId, $query = [])
      * @param string $runId
      * @param array $outputs
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. In Responses API, tool call loops are managed by the application code.
      */
     public function submitToolOutputs($threadId, $runId, $outputs, $stream = null)
     {
@@ -803,6 +1237,7 @@ public function submitToolOutputs($threadId, $runId, $outputs, $stream = null)
      * @param string $threadId
      * @param string $runId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (cancelResponse()).
      */
     public function cancelRun($threadId, $runId)
     {
@@ -816,6 +1251,7 @@ public function cancelRun($threadId, $runId)
     /**
      * @param array $data
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. Migrate to the Responses API (response()).
      */
     public function createThreadAndRun($data)
     {
@@ -831,6 +1267,7 @@ public function createThreadAndRun($data)
      * @param string $runId
      * @param string $stepId
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. In Responses API, run steps are represented as items in response.output.
      */
     public function retrieveRunStep($threadId, $runId, $stepId)
     {
@@ -846,6 +1283,7 @@ public function retrieveRunStep($threadId, $runId, $stepId)
      * @param string $runId
      * @param array $query
      * @return bool|string
+     * @deprecated The Assistants API is being shut down on August 26, 2026. In Responses API, run steps are represented as items in response.output.
      */
     public function listRunSteps($threadId, $runId, $query = [])
     {
diff --git a/src/Url.php b/src/Url.php
index f3c90ef..7fe3dce 100644
--- a/src/Url.php
+++ b/src/Url.php
@@ -161,6 +161,42 @@ public static function chatUrl(): string
         return self::OPEN_AI_URL . "/chat/completions";
     }
 
+    /**
+     * @param
+     * @return string
+     */
+    public static function responsesUrl(): string
+    {
+        return self::OPEN_AI_URL . "/responses";
+    }
+
+    /**
+     * @param
+     * @return string
+     */
+    public static function conversationsUrl(): string
+    {
+        return self::OPEN_AI_URL . "/conversations";
+    }
+
+    /**
+     * @param
+     * @return string
+     */
+    public static function vectorStoresUrl(): string
+    {
+        return self::OPEN_AI_URL . "/vector_stores";
+    }
+
+    /**
+     * @param
+     * @return string
+     */
+    public static function promptsUrl(): string
+    {
+        return self::OPEN_AI_URL . "/prompts";
+    }
+
     /**
      * @param
      * @return string
diff --git a/tests/OpenAiTest.php b/tests/OpenAiTest.php
index 4a27b97..a0837d2 100644
--- a/tests/OpenAiTest.php
+++ b/tests/OpenAiTest.php
@@ -252,7 +252,18 @@
         "presence_penalty" => 0,
     ]);
 
-    $this->assertStringContainsString('text', $result);
+    $this->assertStringContainsString('"object": "chat.completion"', $result);
+    $this->assertStringContainsString('content', $result);
+})->group('working');
+
+it('should throw error when stream true without callback in chat', function () use ($open_ai) {
+    expect(fn () => $open_ai->chat([
+        'model' => 'gpt-3.5-turbo',
+        'messages' => [
+            ['role' => 'user', 'content' => 'Hello'],
+        ],
+        'stream' => true,
+    ]))->toThrow(Exception::class, 'Please provide a stream function. Check https://github.com/orhanerday/open-ai#stream-example for an example.');
 })->group('working');
 
 it('should handle create assistant', function () use ($open_ai) {
@@ -603,3 +614,129 @@
     $this->assertStringContainsString('"object": "list"', $steps);
     $this->assertStringContainsString('data', $steps);
 })->group('working');
+
+it('should handle simple response', function () use ($open_ai) {
+    $result = $open_ai->response([
+        'model' => 'gpt-4o-mini',
+        'input' => 'Say hello in one word.',
+    ]);
+
+    $this->assertStringContainsString('"object": "response"', $result);
+    $this->assertStringContainsString('output', $result);
+})->group('working');
+
+it('should throw error when stream true without callback in response', function () use ($open_ai) {
+    expect(fn () => $open_ai->response([
+        'model' => 'gpt-4o-mini',
+        'input' => 'Hello',
+        'stream' => true,
+    ]))->toThrow(Exception::class, 'Please provide a stream function. Check https://github.com/orhanerday/open-ai#stream-example for an example.');
+})->group('working');
+
+it('should handle response with instructions', function () use ($open_ai) {
+    $result = $open_ai->response([
+        'model' => 'gpt-4o-mini',
+        'instructions' => 'You are a terse assistant. Reply with a single word.',
+        'input' => 'Greet me.',
+    ]);
+
+    $this->assertStringContainsString('"object": "response"', $result);
+    $this->assertStringContainsString('output', $result);
+})->group('working');
+
+it('should retrieve a response', function () use ($open_ai) {
+    $created = $open_ai->response([
+        'model' => 'gpt-4o-mini',
+        'input' => 'Hello.',
+        'store' => true,
+    ]);
+    $id = json_decode($created, true)['id'];
+
+    $result = $open_ai->retrieveResponse($id);
+
+    $this->assertStringContainsString('"id": "'.$id.'"', $result);
+    $this->assertStringContainsString('"object": "response"', $result);
+})->group('working');
+
+it('should list response input items', function () use ($open_ai) {
+    $created = $open_ai->response([
+        'model' => 'gpt-4o-mini',
+        'input' => 'Hello.',
+        'store' => true,
+    ]);
+    $id = json_decode($created, true)['id'];
+
+    $result = $open_ai->listResponseInputItems($id, ['limit' => 10]);
+
+    $this->assertStringContainsString('"object": "list"', $result);
+    $this->assertStringContainsString('data', $result);
+})->group('working');
+
+it('should delete a response', function () use ($open_ai) {
+    $created = $open_ai->response([
+        'model' => 'gpt-4o-mini',
+        'input' => 'Hello.',
+        'store' => true,
+    ]);
+    $id = json_decode($created, true)['id'];
+
+    $result = $open_ai->deleteResponse($id);
+
+    $this->assertStringContainsString('deleted', $result);
+})->group('working');
+
+it('should handle create conversation', function () use ($open_ai) {
+    $result = $open_ai->createConversation([
+        'metadata' => ['topic' => 'demo'],
+    ]);
+
+    $this->assertStringContainsString('"object": "conversation"', $result);
+    $this->assertStringContainsString('id', $result);
+})->group('working');
+
+it('should handle retrieve and delete conversation', function () use ($open_ai) {
+    $created = $open_ai->createConversation();
+    $id = json_decode($created, true)['id'];
+
+    $retrieved = $open_ai->retrieveConversation($id);
+    $this->assertStringContainsString('"object": "conversation"', $retrieved);
+
+    $deleted = $open_ai->deleteConversation($id);
+    $this->assertStringContainsString('deleted', $deleted);
+})->group('working');
+
+it('should handle create and list conversation items', function () use ($open_ai) {
+    $created = $open_ai->createConversation();
+    $id = json_decode($created, true)['id'];
+
+    $items = $open_ai->createConversationItems($id, [
+        'items' => [
+            ['type' => 'message', 'role' => 'user', 'content' => 'Hello.'],
+        ],
+    ]);
+    $this->assertStringContainsString('"object": "list"', $items);
+
+    $list = $open_ai->listConversationItems($id, ['limit' => 10]);
+    $this->assertStringContainsString('"object": "list"', $list);
+    $this->assertStringContainsString('data', $list);
+
+    $open_ai->deleteConversation($id);
+})->group('working');
+
+it('should handle create and delete vector store', function () use ($open_ai) {
+    $created = $open_ai->createVectorStore([
+        'name' => 'test-vs',
+    ]);
+    $this->assertStringContainsString('"object": "vector_store"', $created);
+    $id = json_decode($created, true)['id'];
+
+    $deleted = $open_ai->deleteVectorStore($id);
+    $this->assertStringContainsString('deleted', $deleted);
+})->group('working');
+
+it('should handle list vector stores', function () use ($open_ai) {
+    $result = $open_ai->listVectorStores(['limit' => 5]);
+
+    $this->assertStringContainsString('"object": "list"', $result);
+    $this->assertStringContainsString('data', $result);
+})->group('working');