Codex CLI

OpenAI's own agent. Vendor-locked to OpenAI models; no bring-your-own-key across providers.

Codex CLI — specifications
GitHub stars126K (updated September 2026)
LanguageRust
LicenseApache-2.0
Bring your own keyNo
PricingOpenAI subscription or API billing; OpenAI models only
Footprintn/a
Sandboxn/a

Repository: openai/codex