· Harness/ Head to head

Prime Agent vs Codex CLI

The deciding difference is operational: Prime 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.

Prime Agent

Prime Intellect's recursive-language-model harness — a persistent IPython kernel is the only tool, sub-agents are function calls.

Open source · can be self-hosted

Drops fixed tool schemas and context compaction: the agent writes programs over its own context, and can CRUD its own prompts, skills and sub-agents mid-run.

Codex CLI

OpenAI's terminal coding agent.

Open source · paid · hosted service only

· Side by side/ 4 of 6 differ
Prime AgentCodex CLI
LicenceOpen sourceOpen source
Pricingopen sourcepaid
Self-hostableYesNo
LanguagesAny languageAny language
Installcurl -fsSL https://app.primeintellect.ai/prime-agent/install.sh | shnpm install -g @openai/codex
Keys requiredNoneOPENAI_API_KEY
· Common questions/ FAQ

What is the difference between Prime Agent and Codex CLI?

The deciding difference is operational: Prime 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. Prime Agent: Prime Intellect's recursive-language-model harness — a persistent IPython kernel is the only tool, sub-agents are function calls. Codex CLI: OpenAI's terminal coding agent.

Can Prime Agent and Codex CLI be self-hosted?

Prime Agent can run on your own infrastructure. Codex CLI is a hosted service only.

Are Prime Agent and Codex CLI open source?

Prime Agent is open source (open source). Codex CLI is open source (paid).

Build a stack with Prime AgentAll harness options
· For agents/ This page, machine-readable

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/prime-agent-vs-codex-cli