The OpenAI API lets businesses and developers access all of OpenAI's AI models to build their own products. In 2025, OpenAI also launched AgentKit — a toolkit for enterprises to visually design, deploy, and manage multi-step AI agent workflows. More than 80% of Fortune 500 companies use ChatGPT Enterprise.

The API provides access to all current OpenAI models including GPT-5.x, Codex, Whisper, and image generation through a standardized Responses API. AgentKit includes four components: Agent Builder (a drag-and-drop visual canvas for designing multi-agent workflows), ChatKit (an embeddable chat interface), Connector Registry (a central admin panel for managing data sources), and built-in Evals (tools for testing and optimizing AI prompts). Built-in tools available to agents include web search, file search, computer use, and code execution. Developer SDKs are available for Python, Node.js, and Go.