What Is Grok 4.3?
Grok 4.3 is xAI’s flagship model, now available to all API developers at dramatically reduced pricing: $1.25 per million input tokens and $2.50 per million output tokens — roughly 4x cheaper on input and 10x cheaper on output than competing frontier models. It features a 1-million-token context window, always-on reasoning, native function calling, and ranks #1 on the Artificial Analysis agentic tool-calling leaderboard.
What’s New in Grok Build?
Grok Build is a new coding agent and CLI for professional software engineering. Available in early beta for SuperGrok Heavy subscribers, it supports plan/approve workflows, clean diffs, MCP servers, and parallel subagents. It works with existing AGENTS.md files, plugins, hooks, and skills. A headless mode (-p) enables use inside scripts and automation pipelines.
How Do Grok Skills Work?
Grok Skills, announced May 18, let users define reusable instruction blocks — named capabilities with description and instruction fields — that Grok carries into every future conversation. Skills are importable as .zip, .skill, or .md files, making them shareable and version-controllable. This moves Grok beyond one-shot prompting into a programmable AI workspace with persistent expertise.
What Other Updates Came With Grok 4.3?
The model also supports native video input (up to 5 minutes in mp4, mov, or webm), document generation (PDF, PowerPoint, Excel, Word), and speech-to-text/text-to-speech APIs priced at $4.20 per million characters — 86-92% below OpenAI’s equivalent endpoints. xAI retired eight legacy models on May 15, consolidating around the 4.3 family.