Grok Build is xAI's official command-line coding agent, written in Rust and open-sourced under Apache 2.0 on July 15, 2026, with the repository at xai-org/grok-build. It belongs to the same category as Claude Code and Codex CLI: it understands a repository, edits code and runs commands in the terminal.
Capabilities and Extensions
It supports AGENTS.md, plugins, hooks, skills and MCP servers out of the box, so it plugs into the agent conventions you already use instead of requiring a separate set of configuration habits.
Two changes in September 2026:
- Memory is generally available: it remembers project conventions, decisions and facts across sessions so work resumes with context, and you can see what it has recorded in the read-only
/memorybrowser. - Grok 4.7: released September 21 with a 500K-token context window, it is xAI's recommended model for coding. According to third-party compilations, the faster Grok 4.7 Fast is available only in Cursor and Grok Build, billed at twice the token rate, and isn't included in the free tier.
Getting Started
- Install it with the single curl command from the official announcement (the install script lives at
x.ai/cli/install.sh); documentation is at docs.x.ai. - Sign in with your xAI account, or configure an xAI API key for unattended use.
- Put an AGENTS.md in the repository root describing the project structure, test commands and directories it must not touch; the same file works with other tools that support AGENTS.md.
- Start with small tasks and review the diff before accepting.
Open-Sourcing Came With Backstory
The context is worth stating plainly: on July 10, 2026, reports showed that early versions of the CLI uploaded entire Git repositories — including secrets in .env files — to a cloud storage bucket. xAI disabled the behavior and open-sourced the codebase under Apache 2.0 on July 15, with the project lead saying the goal was to let developers "audit what the tool actually does."
If you ran an old version against a repository containing secrets before July 13, 2026, treat API keys, database passwords, cloud credentials and webhook secrets as leaked and rotate them. That matters more right now than deciding whether to install the new version.
It's a reminder for every coding agent: keep secrets out of the repository, add .env to your ignore list, and block the agent from reading secret files in its permission settings. See our permissions checklist for how.
Who It's For
If you already use Grok and spend your day in the terminal, it's worth a try; if you're just looking for a CLI agent, the ecosystems around Claude Code and Codex are more mature for now. Being open source is a real plus for anyone who needs to audit tool behavior inside a company.
How It Compares
- The most mature ecosystem, with the most documentation and third-party material: Claude Code.
- If you already pay for ChatGPT: OpenAI Codex.
- In Google's ecosystem: the CLI (
agy) in Google Antigravity. The original Gemini CLI stopped serving individual free users and AI Pro and Ultra subscribers on June 18, 2026.
Pricing and Access From China
The CLI itself is open source. According to third-party compilations, as of late August 2026 Grok Build is available on every tier including Free; paid subscriptions such as SuperGrok raise usage limits, and an xAI API key is billed per token. xAI doesn't publish fixed request counts per tier, so rely on what your account shows and the current official pages. Accessing x.ai and related services from mainland China requires your own network arrangements.