The SpaceXSI API is the developer API for the Grok AI models. It is sold by SpaceX Super Intelligence LLC on the x.ai website, and its address, SDK and key names still use "xai". An API (application programming interface) here means that a program sends a request over HTTP and receives the model's output in the reply.
A developer signs up at console.x.ai, creates an API key and sends requests to https://api.x.ai/v1, with the official xai_sdk, the AI SDK, the OpenAI SDK or plain curl. The flagship model, grok-4.7, handles code, reasoning and agentic tool calling, with a context window of 500,000 tokens (a token is a short piece of text, often part of a word). The documentation also covers image understanding, structured outputs, function calling, live web and X search, and search over uploaded files. The Imagine API generates and edits images and video, and the Voice API does speech-to-speech, text-to-speech and speech-to-text. A Playground in the Console tests models without code.
Use is billed per token, image, second or minute, from prepaid credits or, for enterprises, by invoice.