Why is OpenAI deprecating the Assistant API?

OpenAI is consolidating its developer tools and promoting the Responses API as the preferred, more performant alternative. The Assistant API is scheduled for sunset in the first half of 2026.

What’s the main advantage of using the Responses API over the Assistant API?

Responses API delivers significantly lower latency (~50ms vs. 2–3s), more control over assistant behavior, and is actively supported by OpenAI for future enhancements like memory, retrieval, and tool use.

How do I migrate my Assistant-based project to the Responses API using Predictable Dialogs?

Visit https://predictabledialogs.com/docs/providers/openai/create-resource to create a new OpenAI resource. You can configure your model, memory, file search, and tools in just a few guided steps.

Can I add file search (RAG) and function calling with the Responses API?

Yes. Predictable Dialogs supports file search (also known as RAG) out of the box for Responses API resources. Function calling support is in development and will be available soon.

Do I need to be a technical user to make this switch?

No. Predictable Dialogs is built for non-technical users and guides you step-by-step. If you used developers before, they can assist, but you’ll find the platform intuitive and easy to use on your own too.

Why It's Time to Migrate from OpenAI Assistant

As an entrepreneur or business owner leveraging OpenAI Assistant through custom-built APIs or via our platform, it's crucial to stay informed about key changes to OpenAI’s offerings. OpenAI has announced plans to sunset the OpenAI Assistant API by the first half of 2026, with a detailed deprecation plan expected later this year.

In its place, OpenAI strongly recommends migrating to its new Responses API. This new API offers significant performance advantages over both the deprecated Assistant API and the previously used Chat Completions API. For instance, while typical round-trip times for interactions with the OpenAI Assistant API are approximately 2-3 seconds, the Responses API significantly reduces this latency to around 50 milliseconds, providing a noticeably faster and smoother user experience.

If you're currently using PD, or if you've invested in custom development for the Assistant API, migrating to the Responses API is straightforward and seamless. Here’s how you can make this transition easily using Predictable Dialogs:

Step 1: Create a New OpenAI Resource

First, you'll need to set up an OpenAI resource based on the Responses API. Then attach the OpenAI resource created to your agent in the Agent AI screen. Detailed steps for doing this are clearly outlined at Predictable Dialogs Documentation. The process is intuitive and designed specifically for ease of use by non-technical users.

Step 2: Enable Advanced Capabilities like File Search (RAG)

Predictable Dialogs also makes it simple to integrate powerful capabilities such as file search or Retrieval-Augmented Generation (RAG). Using OpenAI’s vector store, documents are uploaded directly to OpenAI without needing to store them on the Predictable Dialogs platform, thus maintaining security and compliance.

In the near future, Predictable Dialogs plans to introduce automated document updates, which might require storing documents temporarily on the platform for enhanced efficiency. This will provide even more streamlined management of your resources.

Detailed guidance on enabling file search within Predictable Dialogs is available here.

Step 3: Incorporate Function Calling (Coming Soon)

Predictable Dialogs is actively developing the capability for function calling within the Responses API. This enhancement, anticipated to arrive shortly, will offer even greater flexibility and functionality for your OpenAI resource.

If You Have Your Own Development Team

Even businesses with in-house development teams, currently managing their OpenAI Assistant integrations independently, can leverage Predictable Dialogs to simplify their transition to the Responses API. Predictable Dialogs offers expert assistance and welcomes the opportunity to support your migration, regardless of your current setup.

We Value Your Feedback

We are committed to making your migration experience as smooth and beneficial as possible. Your insights and feedback about this transition are important to us. Please feel free to reach out and share your thoughts on the new Responses API and how Predictable Dialogs can further assist you in leveraging its capabilities.

By moving early to the Responses API, your business can enjoy enhanced performance and continued support from OpenAI, ensuring you remain ahead in leveraging AI capabilities effectively.