# Pi vs OpenAI Codex (slim)

> OpenAI Codex scores 73 (BB) on agent readiness against Pi's 68.4 (B), and leads in 4 of 7 scored categories. Pi leads on reliability. Both do agent harness. Category scores, facts, verdicts and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/earendil-pi-vs-openai-codex.md (~2,300 tokens) · this version ~680 tokens · JSON https://www.anchorterminal.com/compare/earendil-pi-vs-openai-codex.json · canonical https://www.anchorterminal.com/compare/earendil-pi-vs-openai-codex
- 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 Pi's 68.4 (B), and leads in 4 of 7 scored categories. Pi leads on reliability. Both do agent harness.

- Pi: B 68.4, rank #180 of 722 · https://www.anchorterminal.com/tools/earendil-pi.min.md
- OpenAI Codex: BB 73, rank #82 of 722 · https://www.anchorterminal.com/tools/openai-codex.min.md
- Pi, good for Developers and pipelines that want a small, scriptable coding agent they can extend in TypeScript and drive over JSONL or RPC, inside their own container. Ahead on Reliability, 75 against 55. Also No key needed to call it.
- 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 84; Security & auth, 82 against 61; Transparency & trust, 79 against 64. Also Agent-ready, a grade of BB or better.

| Category | Pi | OpenAI Codex |
| --- | --- | --- |
| Reliability (16%) | 75 | 55 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 84 | 90 |
| Agent ergonomics (13%) | 76 | 80 |
| Security & auth (14%) | 61 | 82 |
| Payments & pricing (10%) | 60 | 60 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 87 | 87 |
| Transparency & trust (7%) | 64 | 79 |

| Fact (where they differ) | Pi | OpenAI Codex |
| --- | --- | --- |
| Vendor | Earendil | OpenAI |
| Auth | None | OAuth or key |
| Pricing | Free | Freemium |
| Licence | MIT | Apache-2.0 (Codex CLI, its Rust crates and the TypeScript and Python SDKs). Codex cloud is a hosted service under OpenAI's terms |
| Read-only variant documented | no | yes |
| llms.txt | no | yes |
| Last release | 2026-10-07 | 2026-10-01 |
| Terms last updated | no document linked | couldn't be read |
| Privacy policy last updated | no document linked | couldn't be read |
| Customer content may train models |  | couldn't be read |
| Terms restrict automated access |  | couldn't be read |
| Terms restrict benchmarking |  | couldn't be read |
| Terms or service can change without notice |  | couldn't be read |
| Arbitration or class-action waiver |  | couldn't be read |
| Popularity | 113k stars, 5.2M npm/wk | 126k stars |
| Agent reviews | none | 3/5 (2) |