xAI unveils Grok Code Fast 1, a fast model for programming

xAI has just unveiled grok-code-fast-1, a model designed to speed up programming workflows where tool calls and reasoning loops are usually slow.

Can you imagine an assistant inside your IDE that has already made several tool calls before you finish reading the problem? (x.ai)

What is Grok Code Fast 1 and why it matters

grok-code-fast-1 is a new model built from scratch with an architecture focused on agentic coding tasks. It was trained on a predominantly technical corpus and fine-tuned with datasets that simulate pull requests and real development tasks.

The goal was for it to understand and use common tools like grep, the terminal, and file editing naturally within workflows. (x.ai)

So what does that mean for your day-to-day? If you work on prototypes, quick fixes, or integrations where you iterate a lot, speed and familiarity with real tools change how productive you feel.

Speed and techniques behind the performance

The xAI team applied inference and supercomputing optimizations to deliver faster responses. They also invested in prompt caching, reaching cache hit rates above 90% with their launch partners.

In practice that means more immediate replies and less latency when the model repeats common patterns. (x.ai)

Their internal metrics show high Tokens per Second and comparisons against other models, noting those tests called each corresponding API. They also report a 70.8% score on a verified subset of SWE-Bench using their own evaluation harness. (x.ai)

Price and initial access

xAI positions grok-code-fast-1 as an economical option for everyday development tasks:

• $0.20 per 1M input tokens
• $1.50 per 1M output tokens
• $0.02 per 1M cached input tokens

They also offer limited-time free access through selected partners during the launch. (x.ai)

Where to try it and the ecosystem

Since the stealth launch under the codename sonic, xAI has worked with partners to integrate the model into agentic coding platforms. Launch partners include GitHub Copilot, Cursor, Cline, Roo Code, Kilo Code, opencode and Windsurf, letting you try the model free for a limited time. (x.ai)

Grok Code Fast is intended to be a daily driver: fast, efficient, and low-cost for common engineering tasks.

Practical recommendations to get started

1. If you already use assistants in your editor, try breaking large tasks into smaller subtasks. The creators note that with faster responses it's better to give shorter instructions and iterate. (x.ai)

2. Take advantage of the model's ability to handle real tools. Ask for concrete steps that involve terminal commands or file changes, and verify each step in a controlled environment.

3. Review xAI's Prompt Engineering guide and the model card to understand limitations, best practices, and how to leverage caching in your workflow. (x.ai)

What to expect soon

xAI announces frequent updates with short turnaround times, and they're already working on variants that support multimodal input, parallel tool calls, and extended context.

If you're curious to experiment, the community feedback phase is open and they plan to iterate quickly on comments. (x.ai)

Think of this as a tool meant to reduce technical friction on repetitive tasks and speed up your development cycles. Want to try a workflow where the assistant has already explored files and run commands before you finish describing the problem? That's exactly what this model aims for.