agentty vs Gemini CLI

agentty vs Gemini CLI: an honest comparison (2026)

Short answer: Gemini CLI is Google's open-source agent with a generous free tier and huge context windows. agentty also runs Gemini, plus Claude, GPT, Copilot, Kimi and local models, and is ready to type in 47 ms instead of 3.0 s, idling at 21 MB instead of 441 MB.

Both are open-source terminal coding agents. Gemini CLI is Google's agent, written in TypeScript and running on Node.js. agentty is a C++26 agent harness shipped as one static binary that works with any provider, Gemini included.

Measured

Both installed the official way on the same machine, fresh home directory, no login. Gemini CLI's disk figure includes the Node.js runtime it needs. Median of 10 launches, measured 2026-11-09 against Gemini CLI 0.67.0.

launch → ready to type lower is better
  1. agentty47 ms
  2. Gemini CLI3.0 s65×
memory while idle lower is better
  1. agentty21 MB
  2. Gemini CLI441 MB21×
on disk, with runtime lower is better
  1. agentty23 MB
  2. Gemini CLI197 MB8.6×

median of 10 launches · same machine · fresh install, no login · method & all numbers

At a glance

agentty Gemini CLI
Built with C++26, one static binary TypeScript on Node.js
Ready to type 47 ms 3.0 s
Memory while idle 21 MB 441 MB
On disk 23 MB 197 MB
Models Gemini, Claude, GPT, Copilot, Kimi, DeepSeek, Grok, Mistral, Groq, OpenRouter, local Ollama Gemini; local Gemma
Sign in with a plan Claude Pro/Max, ChatGPT, GitHub Copilot, Kimi Google account
Shell sandbox On by default, enforced by the OS Optional (--sandbox)
Editors Zed and JetBrains over ACP ACP; VS Code companion
License MIT Apache-2.0

Where Gemini CLI is ahead

  • Free tier. Sign in with a Google account and get a generous free daily quota.
  • Context window. Gemini models take very large inputs, handy for reading big codebases in one go.
  • Google integrations. Search grounding and Google's own tooling built in.

Where agentty is ahead

  • Speed and footprint. 65× faster to a usable prompt, 21× less memory while idle, with no Node.js to install.
  • Any model. Use Gemini with an API key, and switch to Claude, GPT or a local model mid-thread.
  • Sandboxed by default. No flag to remember; credentials like ~/.ssh and .env are masked.
  • Retrieval. A local search engine sends only the code that matters, instead of relying on a huge context.

Which should you choose?

  • Gemini CLI if you want Google's free tier and only use Gemini.
  • agentty if you want a fast, light agent that can use Gemini and everything else.

Install in one line

bash
curl -fsSL https://agentty.org/install.sh | sh

Ready to try it? One line, no Node or Python.

curl -fsSL https://agentty.org/install.sh | sh
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