xAI API offers programmatic access to the Grok series foundational models, supporting both text and image inputs with a context length of 128,000 tokens, along with function calls and system prompts. This API is fully compatible with OpenAI and Anthropic APIs, simplifying the migration process. Background information indicates that xAI is currently in public beta testing until the end of 2024, during which each user can receive $25 worth of free API credits per month.