Agent CLI comparison (2026): six terminal coding agents

What this page compares, and how a cell is decided

Six coding agents that live in a terminal: Claude Code, Codex CLI, Grok Build, Kimi Code CLI, OpenCode and Cursor CLI. Every figure below was read from the vendor’s own documentation, repository or registry entry on 22 September 2026, and nothing here is sourced from a roundup, a forum post or another comparison page.

One convention matters more than any individual cell. Where a vendor does not document a capability, this page prints a dash, never a no. A dash means we could not find the vendor saying it — it is a statement about the documentation, not about the product. Several dashes below almost certainly hide a feature that exists and is simply unwritten, and turning them into a no would be the most common way these comparisons get things wrong.

The six in one line each

• Claude Code — Anthropic’s agent, subscription-gated: the free claude.ai plan does not include it. Deepest worktree and session tooling of the six. Covered in the Claude Code introduction.
• Codex CLI — OpenAI’s agent, Apache-2.0 and Rust, driven by a ChatGPT sign-in or an API key. Strong sandbox and approval configuration; see the Codex CLI workflow guide.
• Grok Build — xAI’s agent, what people search for as “Grok CLI”. Apache-2.0, first-class worktrees, a kernel sandbox that ships off by default. See the Grok CLI guide.
• Kimi Code CLI — Moonshot’s agent, what people search for as “Kimi CLI”. MIT, million-token model, AGENTS.md only. See the Kimi CLI guide.
• OpenCode — the open-source one, MIT, now published by Anomaly, and now shipping two incompatible major versions at once. See the OpenCode guide.
• Cursor CLI — Cursor’s terminal agent, installed as agent, closed source, with Cursor brokering all inference. See the Cursor CLI guide.

Capability matrix

Install, auth and version

Platform support is close to uniform and the caveats are where the differences live. Claude Code documents macOS Ventura or newer, Windows 10 1809 or Server 2019 and newer, Ubuntu 20.04, Debian 10 or Alpine 3.19 and newer, with 4 GB of RAM on x64 or ARM64. Grok Build calls its Windows builds best-effort and tells you to run the installer under Git for Windows or MSYS2 Bash. Kimi Code needs Git for Windows present because it uses the bundled Git Bash as its shell. OpenCode v1 recommends WSL over native Windows; OpenCode v2 states that Windows package managers are not supported. Cursor documents macOS, Linux and WSL together, plus a separate native Windows installer, and does not express a preference between them.

What each one costs

Three metering models are in play and they are not comparable. Anthropic and OpenAI meter in opaque units over time windows. OpenCode Go meters in dollars, which is the only one you can reason about arithmetically. Cursor meters in two pools split by model family. If you are trying to work out whether a second subscription pays for itself, the AI subscription audit is that question written down as a procedure, and the usage limits guide covers what actually happens when a window closes mid-task.

Models and context windows

One structural difference cuts across the table. OpenCode treats the context window as configuration you assert about a model you chose; Cursor treats the model list as something it hands you. Everyone else sits in between. That is the same axis as bring-your-own-key in the matrix above, and it decides how much of your agent setup survives changing vendors.

Instruction files: AGENTS.md is winning

The most useful thing you can know about running several of these at once is which file each of them reads. Five of the six read AGENTS.md. One of them reads it exclusively. Three also read CLAUDE.md, one of them reads only CLAUDE.md, and one dropped CLAUDE.md deliberately in its second major version.

Sessions and resume

Every one of the six persists sessions locally, and every one of them uses a different layout to do it. That is precisely why supervising several at once is harder than running any one of them — managing multiple sessions covers the problem for a single agent, and it compounds per additional CLI.

Two renames, one org move, and a name collision

Half of this comparison changed identity during 2026. None of these are cosmetic: each one changes the repository you should be reading, the package you should be installing, or both.

• Grok CLI is Grok Build. The repository is xai-org/grok-build and the docs are under docs.x.ai/build. The binary is still grok, which is why the rename is easy to miss. Separately, an unaffiliated community project at superagent-ai/grok-cli also uses the name and publishes as grok-dev; it has had no commit or release since May 2026. The Grok CLI guide separates the two.
• Kimi CLI is Kimi Code CLI. The Python MoonshotAI/kimi-cli is archived — read-only, no further releases, fixes or security updates, and existing installations stated to be unsupported and due to stop working. The replacement is MoonshotAI/kimi-code, and the binary is still kimi. The Kimi CLI guide has the migration path.
• OpenCode moved organisation. github.com/sst/opencode now redirects to github.com/anomalyco/opencode, and the sst organisation bio says so directly. The publisher is Anomaly.
• OpenCode shipped a second, separate distribution. v1 and v2 use different npm packages, install scripts, Homebrew formulae and documentation sites, and cannot be installed side by side by default. Both lines are live.
• A different project was also called OpenCode. opencode-ai/opencode is archived and became Crush under the Charm team — while opencode-ai is simultaneously the npm package name of the surviving OpenCode v1. Anything written about “opencode” before that split may be about the wrong product. The OpenCode guide untangles all three.
• Cursor’s binary is now agent. cursor-agent survives only as a legacy symlink the installer still creates, so most existing third-party guides still name it. The Cursor CLI guide covers what changed around it.

Running more than one of them at once

Most people end up with two or three of these rather than one, because the plans are not interchangeable and neither are the strengths. Claude Code vs Codex is the comparison with benchmarks and cost-per-task figures attached, and running them in parallel is the worktree-based setup that keeps two agents from editing the same files.

The mechanics generalise across all six. Give each agent its own worktree, keep one written brief and one verification command, and never paste one agent’s output into another’s trial if you want an independent result. Four of the six ship a worktree flag; for Codex and Kimi Code you prepare the checkout yourself with git worktree add.

git worktree add -b trial/claude ../trial-claude HEAD
git worktree add -b trial/codex  ../trial-codex  HEAD
git worktree add -b trial/grok   ../trial-grok   HEAD

(cd ../trial-claude && claude --version)
(cd ../trial-codex  && codex --version)
(cd ../trial-grok   && grok --version)

CmdBrief is the Mac workspace built for exactly that: it runs Claude Code, Codex, Grok CLI, Kimi CLI, OpenCode and Cursor CLI in named per-product workspaces (Claude, Codex, Grok and Cursor can lead), shows working, needs-input and done states per pane, and reads each agent’s own session store so history stays attached to the product it belongs to. Usage windows appear where the provider exposes them — five-hour and weekly for Claude Code and Codex, weekly credits for Grok CLI, rolling, weekly and monthly for OpenCode Go plans, and monthly Cursor Models and Other Models pools for Cursor CLI. Kimi exposes none, so none is shown.

If the question is which workspace to run them in rather than which agent to run, the tool comparisons cover that side, including CmdBrief against Cursor.

Primary sources

Provider terms and product behavior can change. Confirm plan, pricing, model, and permission details in the current official documentation.

• 01Claude Code documentationcode.claude.com
• 02Claude Code CLI referencecode.claude.com
• 03Claude pricingclaude.com
• 04Codex CLI documentationlearn.chatgpt.com
• 05ChatGPT and Codex pricinglearn.chatgpt.com
• 06Grok Build overviewdocs.x.ai
• 07Grok Build CLI referencedocs.x.ai
• 08Kimi Code CLI repositorygithub.com
• 09Kimi Code CLI: the kimi commandmoonshotai.github.io
• 10OpenCode documentation (v1)opencode.ai
• 11OpenCode documentation (v2)opencode.ai
• 12Cursor CLI overviewcursor.com
• 13Cursor CLI parameter referencecursor.com
• 14Cursor pricingcursor.com
• 15Git worktree documentationgit-scm.com