Codex (OpenAI)
Free tier available
- Free$0
- Go$8/mo
- Plus$20/mo

Codex (OpenAI)
GPT-5.2-Codex (default 2026-04-23) / GPT-5.5 / GPT-5.4
Our pickHermes Agent
Tier-list head-to-head. Hermes Agent takes the A-tier slot — here's the breakdown.
Spec sheet
| Tier | A-tier | A-tierwin |
| Overall score | 8.3 / 10 | 8.4 / 10win |
| Powered by | GPT-5.2-Codex (default 2026-04-23) / GPT-5.5 / GPT-5.4 | — |
| Free tier | Yes | Yes |
| Starting price | $0 | $0 |
| Best for | Developers already paying for ChatGPT Plus who want a coding agent at no extra cost. | Power users and technical teams who will actually use an agent daily, give it real work, and benefit from a… |
| Last reviewed | 2026-04-25 | 2026-05-05 |
Head-to-head
Rated 1-10 on the same rubric across all 130 tools we cover.
What you'll pay
Look past the headline number -- entry-tier limits drive most cost surprises.
Free tier available
Free tier available
GPT-5.2-Codex (launched 2026-04-23 -- SOTA on SWE-Bench Pro and Terminal-Bench 2.0; first-party scores below pending detailed third-party verification) benchmarks — Hermes Agent has no published benchmarks
| Benchmark | Description | Score |
|---|---|---|
| SWE-bench | Real GitHub issue fixing | 72% |
| HumanEval | Python code generation | 95% |
The decision
Use-case anchors and category strengths, side by side.
Developers already paying for ChatGPT Plus who want a coding agent at no extra cost. Especially good for parallel task execution -- assign multiple bug fixes or feature branches and let Codex work them simultaneously.
Visit Codex (OpenAI)Power users and technical teams who will actually use an agent daily, give it real work, and benefit from a learning loop. Teams running it on a real server with Docker or Modal sandboxing get the most out of it. Also the right pick if you care about model sovereignty -- it runs on anything.
Visit Hermes AgentBottom line
Codex (OpenAI) (A-tier, 8.3/10) and Hermes Agent (A-tier, 8.4/10) are within margin-of-error of each other on overall score. There's no decisive winner -- the right pick comes down to how you'll actually use the tool, not which scored higher in the abstract. We rate them on the same rubric (ease of use, output quality, value, features), and on this pair the rubric is calling it a draw.
Pricing-wise, both tools have a free tier (Codex (OpenAI) starts $0, Hermes Agent starts $0), so you can test either without committing. Compare what each free tier actually unlocks -- usage caps, model access, and feature gates differ a lot more than the headline price suggests, especially as both vendors have tightened limits in 2026.
By use case: pick Codex (OpenAI) when developers already paying for chatgpt plus who want a coding agent at no extra cost. Pick Hermes Agent when power users and technical teams who will actually use an agent daily, give it real work, and benefit from a learning loop. The two tools aren't fighting for the same person -- they're aiming at adjacent jobs that occasionally overlap. If you're squarely in Hermes Agent's lane, the tier-list ranking and the use-case fit point the same direction; if you're in Codex (OpenAI)'s lane, the score gap matters less than the fit.
Bottom line: this pair is a coin flip on raw scores. Choose by use-case fit, free-tier availability, and which one you can actually try without committing. Re-evaluate in 60-90 days -- both vendors are shipping fast in 2026.
Keep digging
Full Codex (OpenAI) review
Tier A · 8.3/10
Full Hermes Agent review
Tier A · 8.4/10
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Built from our daily AI-tool sweep, last touched May 5, 2026. Honest tier-list reviews — no affiliate-link pieces disguised as advice. See the rubric or how we review.