Spring AI: First REST endpoint with OpenAI (2026)

Learn to create your first REST endpoint with Spring AI and OpenAI. Step-by-step tutorial with Java, ChatClient, and Spring Boot. Try it with curl!

miércoles, 1 de julio de 2026 • 4 min read • Q2BSTUDIO Team

Step-by-step guide to your first AI endpoint

The backend development ecosystem is undergoing a silent but profound transformation: the integration of large language models (LLMs) directly into enterprise REST APIs. Spring AI, the project that extends the Spring Boot ecosystem to work with providers like OpenAI, allows engineering teams to incorporate artificial intelligence capabilities without having to leave their familiar Java stack. What a few years ago required complex infrastructures and teams specialized in machine learning, today can be solved with a few beans and an endpoint configured with good cybersecurity practices and AWS and Azure cloud services.

The typical architecture of a conversational endpoint consists of a REST controller that receives a message from the client, sends it to a chat client configured with the desired model — for example gpt-4o-mini — and returns the response in JSON. However, the real value is not in the boilerplate code, but in how API keys are managed, how the transport layer is protected, and how the service scales when the number of requests grows. This is where the experience of a company like Q2BSTUDIO comes in, specialized in the development of custom applications that not only connect with OpenAI, but also integrate AI agents capable of orchestrating multiple calls, managing context, and delegating tasks to external systems.

Let's think of a real case: a company that needs an internal assistant to query sales databases, generate reports in Power BI, and answer questions in natural language. A developer could quickly create a prototype with Spring AI and a couple of annotations, but the production-ready version requires custom software that includes federated authentication, rate limiting, audit logging, and automated deployment on AWS and Azure cloud services. Furthermore, API Key security is critical: it should never appear in the repository, but rather be managed through secrets in cloud infrastructure or a corporate vault, an area where Q2BSTUDIO's cybersecurity services add value.

From a technical point of view, the ChatClient configuration allows defining a system prompt that shapes the assistant's behavior. But beyond that, the real power emerges when we combine that client with business intelligence services and real-time data pipelines. For example, an endpoint could receive a query, enrich it with data from a data warehouse, pass it to the model, and return not only the textual response but also embedded visualizations. This transforms AI for businesses from an experiment into a tangible productivity tool.

The next natural step is the implementation of AI agents that, instead of answering a single question, execute a multi-step plan: search for information in internal documents, calculate metrics, and format the response into an executive report. Spring AI already offers tools to build these flows, but robust orchestration and fault tolerance require a well-designed architecture. Here, the alliance with a technology partner like Q2BSTUDIO allows addressing both the business logic layer and the integration with legacy systems or ERPs.

For organizations that already use Power BI as a reporting tool, adding a conversational endpoint that allows asking questions in natural language about the same data unifies the user experience. The Q2BSTUDIO team has worked on projects where the assistant interacted directly with Power BI Embedded APIs, returning responses enriched with dynamic charts. All of this deployed on AWS and Azure cloud services with auto-scaling and load balancing policies, ensuring availability even during demand spikes.

The trend for 2026 is clear: more and more applications will incorporate conversational interfaces as the main interaction channel. From customer portals to internal management systems, artificial intelligence stops being a decoration to become a fundamental pillar. But that leap is only possible if you have custom software that respects security, performance, and maintainability standards. Therefore, trusting a company with proven experience in custom application development, such as Q2BSTUDIO, ensures that every integration with language models is carried out on solid foundations.

If your organization is evaluating taking the step towards intelligent APIs, remember that the path does not end with the first endpoint. True maturity comes when you manage to combine cybersecurity, AWS and Azure cloud services, and business intelligence services in a single solution. Spring AI is an excellent entry point; the rest is a matter of architecture, experience, and the right support from a team that understands both Java and business strategy.

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