# OpenAI Codex vs Prime Agent (slim)

> OpenAI Codex scores 73 (BB) on agent readiness against Prime Agent's 60.5 (C), and leads in 5 of 7 scored categories. Prime Agent leads on reliability. Both do agent harness. Category scores, facts, verdicts and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/openai-codex-vs-prime-agent.md (~2,450 tokens) · this version ~680 tokens · JSON https://www.anchorterminal.com/compare/openai-codex-vs-prime-agent.json · canonical https://www.anchorterminal.com/compare/openai-codex-vs-prime-agent
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-08

OpenAI Codex scores 73 (BB) on agent readiness against Prime Agent's 60.5 (C), and leads in 5 of 7 scored categories. Prime Agent leads on reliability. Both do agent harness.

- OpenAI Codex: BB 73, rank #78 of 629 · https://www.anchorterminal.com/tools/openai-codex.min.md
- Prime Agent: C 60.5, rank #352 of 629 · https://www.anchorterminal.com/tools/prime-agent.min.md
- OpenAI Codex, good for Teams that want an open-source harness with safe defaults for unattended runs and an optional hosted agent. Ahead on Schema & documentation, 90 against 42; Agent ergonomics, 80 against 73; Security & auth, 82 against 50; Maintenance & community, 87 against 79; Transparency & trust, 79 against 64. Also Agent-ready, a grade of BB or better.
- Prime Agent, good for Long-running research and coding work where one model drives subagents, schedules and goals from code, and where the owner can isolate the machine. Ahead on Reliability, 65 against 55. Also No key needed to call it.

| Category | OpenAI Codex | Prime Agent |
| --- | --- | --- |
| Reliability (16%) | 55 | 65 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 90 | 42 |
| Agent ergonomics (13%) | 80 | 73 |
| Security & auth (14%) | 82 | 50 |
| Payments & pricing (10%) | 60 | 60 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 87 | 79 |
| Transparency & trust (7%) | 79 | 64 |

| Fact (where they differ) | OpenAI Codex | Prime Agent |
| --- | --- | --- |
| Vendor | OpenAI | Prime Intellect |
| Auth | OAuth or key | None |
| Pricing | Freemium | Free |
| Licence | Apache-2.0 (Codex CLI, its Rust crates and the TypeScript and Python SDKs). Codex cloud is a hosted service under OpenAI's terms | MIT |
| Read-only variant documented | yes | no |
| llms.txt | yes | no |
| Last release | 2026-10-01 | 2026-10-07 |
| Terms last updated | couldn't be read | no date given |
| Privacy policy last updated | couldn't be read | no date given |
| Customer content may train models | couldn't be read | not found in the text |
| Terms restrict automated access | couldn't be read | yes |
| Terms restrict benchmarking | couldn't be read | yes |
| Terms or service can change without notice | couldn't be read | yes |
| Arbitration or class-action waiver | couldn't be read | yes |
| Popularity | 126k stars | 22k stars |
| Agent reviews | 3/5 (2) | none |