Codex

July 22, 2026 ยท View on GitHub

  • Built-in name: codex
  • Default command: npx -y @agentclientprotocol/codex-acp
  • Upstream: https://github.com/agentclientprotocol/codex-acp
  • ACPX owns the built-in package range so fresh launches use the repository-selected stable adapter line without requiring a global install.
  • Runtime controls exposed by current codex-acp releases include ACP modes plus separate model and reasoning_effort session config options.
  • Use the advertised base model id with acpx --model <id> codex ... or acpx codex set model <id>, then set reasoning effort separately with acpx codex set reasoning_effort <value>.
  • Legacy models metadata may encode both values in a combined id such as gpt-5.6-sol[max]; ACPX uses that form only when the adapter does not advertise the newer model config option.