SpaceXAI Open-Sources Grok Build AI Coding Agent

SpaceXAI released Grok Build, the terminal-based AI coding agent that powers its grok CLI, on GitHub today. This open-source release includes the agent harness, a text-based user interface (TUI), the CLI shell, and developer tooling, all licensed under the Apache 2.0 license. Grok Build functions as an agent designed to understand codebases, modify files, execute shell commands, and perform web searches, while also managing long-running tasks.

The agent operates as a full-screen, mouse-interactive TUI, offering three distinct operational surfaces: the interactive TUI, a headless mode for scripting and continuous integration (CI) pipelines, and integration into editors via the Agent Client Protocol (ACP). The published code is organized into four main areas: the agent loop, which handles context assembly, response parsing, and tool-call dispatch; the tools, responsible for reading, editing, and searching code; the terminal UI, managing rendering, input, plan review, and an inline diff viewer; and the extension system, encompassing skills, plugins, hooks, MCP servers, and subagents.

These functional areas correspond to specific Rust crates within the repository. The `xai-grok-shell` crate serves as the agent runtime, providing entry points for leader, standard input/output, and headless operations. The `xai-grok-tools` crate contains implementations for terminal interactions, file editing, and search functionalities. The `xai-grok-workspace` crate manages the host filesystem, version control system (VCS) integration, execution, and checkpointing. The `xai-grok-pager` crate specifically handles the TUI's scrollback, prompt, modal windows, and rendering. A `crates/codegen/xai-grok-pager-bin` crate is also present for composing the `xai-grok-pager` binary. The `third_party` directory contains vendored upstream source code, including the Mermaid diagram stack.