Is Codex or Gemini CLI more reliable?

Based on StupidLLM's incident database, Codex has 3 documented failures (avg severity 5.8/10) while Gemini CLI has 4 (avg severity 9.4/10). Codex shows better reliability.

What are the main differences between Codex and Gemini CLI failures?

Codex's most common failure mode is Destructive Action, while Gemini CLI most commonly fails via Destructive Action. Codex has 0 critical incidents vs Gemini CLI's 3.

Which has more critical-severity failures?

Gemini CLI has more critical failures (3 vs 0), indicating a higher likelihood of severe, production-impacting incidents.

Should I use Codex or Gemini CLI for production code?

Codex has a lower average failure severity (5.8/10 vs 9.4/10), making it the statistically safer choice for production environments. However, both agents have documented critical incidents — no AI coding agent is risk-free.

How many verified incidents does each agent have?

Codex has 2 verified incidents out of 3 total, while Gemini CLI has 4 verified out of 4. Verified incidents are confirmed against source evidence.

Head to head

Codex vs Gemini CLI

Comparing 3 documented Codex incidents against 4 for Gemini CLI.

Full Codexreport →Full Gemini CLIreport →

Verdict

Codex has the lower average failure severity (5.8/10 vs 9.4/10), making it the statistically safer choice of the two — though both agents have documented critical incidents.