grok-build

xAI‘s open-source terminal coding agent, grok — a full-screen TUI written in Rust that “understands your codebase, edits files, executes shell commands, searches the web, and manages long-running tasks.” The repo is synced periodically from xAI’s internal monorepo. It is the agentic-coding-harness pattern shipped first-party by a frontier model lab — a direct peer to Claude Code and Gemini CLI, now with a Grok-branded entrant.

What it is

• A grok CLI/TUI: mouse-interactive, full-screen, for AI-assisted coding.
• Three run modes — interactive TUI, headless scripting / CI integration, or embedded in editors via the Agent Client Protocol (ACP).
• Tools for file editing, shell/terminal execution, and search; web search built in; long-running task management.
• Extensible through MCP servers and plugins.
• Cross-platform: macOS, Linux, Windows.

Architecture (modular Rust crates)

The repo splits the harness into single-concern crates — an architecture that mirrors the agent-middleware “compose from small pieces” bet, done at the crate level:

• xai-grok-pager — TUI rendering and interaction.
• xai-grok-shell — the agent runtime loop.
• xai-grok-tools — tool implementations (file edit, terminal exec, search).
• xai-grok-workspace — workspace management (filesystem, version control, execution).

Why it routed here

grok-build is squarely the agentic coding harness as a product: the scaffolding wrapped around a code-writing model (task selection, editing, shell, web, durable tasks) — “everything else” beyond generating tokens agentic-coding-harness. What distinguishes it from the many community harnesses here (claw-code, oh-my-pi, easy-agent) is provenance: it is vendor-first-party, the model lab shipping its own open harness rather than a third party re-implementing one. That it is Rust and open-source places it beside claw-code (the community Rust CLI harness) on the systems-language end of the spectrum, but with xAI’s weight behind it. Its ACP editor-embedding mode and MCP + plugin extensibility are the same interop surfaces (agent↔editor, agent↔tool) the rest of this spoke tracks — evidence the harness layer is converging on shared protocols regardless of which lab ships it.

Cross-wiki: the Grok model / xAI as a provider lives in ../llm-providers-wiki (xai-grok); this page is the harness/tooling face. The model is the substrate; the value here is the wrapping — the recurring structure-over-capability thesis, now instantiated by the lab that makes the model.

Related

agentic-coding-harness · claw-code · oh-my-pi · easy-agent · model-context-protocol · agent-middleware · xai-grok