Skip to content

Agent field guideCoding harness

Grok Build

situational

SpaceXAI · beta · osi-open-source

Open-source terminal coding harness with TUI, headless automation, ACP, plugins, and sandbox controls.

Visit docs.x.ai →Open in NoemiumSource verified 2026-08-19

ledger entry · observed by @whysanesanders

The harness is broad, open, and no longer just a thin model wrapper. It is a credible alternative when Grok access or its headless mode fits the job, but it still has the normal high-risk coding-agent surface and needs sandbox and permission rules before unattended use.

layer

Coding harness

maturity

beta

deployment

local · hybrid

evidence

Source verified

Install

command · macOS, Linux, WSL, or Git Bash

curl -fsSL https://x.ai/cli/install.sh | bash
official install source →

command · Windows PowerShell

irm https://x.ai/cli/install.ps1 | iex
official install source →

Best for

  • Terminal-first repository work with Grok models
  • Headless coding jobs and CI-friendly structured output
  • Teams that need ACP, plugins, MCP, worktrees, and explicit permission rules

Requirements

  • macOS, Linux, WSL, Git Bash, or Windows PowerShell
  • Browser authentication for an eligible Grok account, or XAI_API_KEY for headless use
  • A repository or working directory the harness is allowed to inspect and modify

Real cost scenarios

Open-source harness only

$0/mo

Binary and source are free; model access is excluded.

SuperGrok subscription route

$30/mo

Current SuperGrok monthly price; actual Build limits depend on the plan.

API or custom endpoint

$0+/mo

Pay-as-you-go total depends on the selected model, token volume, and endpoint.

Models and providers

Grok subscriptionxAI APIcustom OpenAI-compatible endpoint

Channels and surfaces

interactive terminal TUIheadless CLI and CIACP-compatible editors

Security boundary

high privilege

Source code and tool results stay local until sent to the configured model or remote tools.

  • Keep --always-approve and equivalent YOLO modes out of persistent environments.
  • Use allow and deny rules plus a sandbox profile for unattended or untrusted repositories.
  • Review plugin, MCP, hook, and marketplace sources before enabling them.

Known limitations

  • Model usage is not free merely because the harness source is Apache-2.0.
  • Custom endpoints can differ materially in tool-calling quality and privacy.
  • Local shell, plugin, hook, and MCP access create a large supply-chain surface.

Typed evidence

  1. 1Availabilitydocs.x.ai/build/overviewchecked 2026-08-19
  2. 2Installdocs.x.ai/build/overviewchecked 2026-08-19
  3. 3Requirementsdocs.x.ai/build/overviewchecked 2026-08-19
  4. 4Pricingx.ai/pricingchecked 2026-08-17
  5. 5Licensegithub.com/xai-org/grok-build/blob/main/LICENSEchecked 2026-08-19
  6. 6Security / threat modeldocs.x.ai/build/cli/referencechecked 2026-08-19

Edit this guide on GitHub