The deciding difference is operational: Hermes Agent can run on infrastructure you control, Codex CLI cannot. If that constraint is real for you, it settles the choice before anything else is considered.
Self-improving agent from Nous Research — writes its own skills from experience and carries them forward.
The learning loop is the point: it creates skills after complex tasks and searches its own past sessions. Runs anywhere from a $5 VPS to Modal or Vercel Sandbox.
OpenAI's terminal coding agent.
| Hermes Agent | Codex CLI | |
|---|---|---|
| Licence | Open source | Open source |
| Pricing | open source | paid |
| Self-hostable | Yes | No |
| Languages | Any language | Any language |
| Install | curl -fsSL https://hermes-agent.nousresearch.com/install.sh | bash | npm install -g @openai/codex |
| Keys required | None | OPENAI_API_KEY |
The deciding difference is operational: Hermes Agent can run on infrastructure you control, Codex CLI cannot. If that constraint is real for you, it settles the choice before anything else is considered. Hermes Agent: Self-improving agent from Nous Research — writes its own skills from experience and carries them forward. Codex CLI: OpenAI's terminal coding agent.
Hermes Agent can run on your own infrastructure. Codex CLI is a hosted service only.
Hermes Agent is open source (open source). Codex CLI is open source (paid).
Every page here answers to Accept: text/markdown and returns the same content at roughly a tenth the tokens. No separate site, no toggle — same URL.
curl -s -H "Accept: text/markdown" https://newagent.build/compare/hermes-agent-vs-codex-cli