claude-code + claude-opus-5 vs codex-cli + gpt-5.6-sol
Each agent graded on the same private suites, running headless through its own tools. Deltas are oriented so a win is a win, whichever way the metric runs.
claude-cliclaude-code + claude-opus-5Solves up to tier 5 at 64.0% of Claude Max 5x per run · 1.6 runs/5hoverall pendingcodex-clicodex-cli + gpt-5.6-solSolves up to tier 5 at 3.6% of ChatGPT Plus per run · 27.8 runs/weekoverall pending
real-world@v3CvsD
| Dimension | claude-code + claude-opus-5 | codex-cli + gpt-5.6-sol | Delta |
|---|---|---|---|
| Capability | 60% | 47% | 13% · claude-code + claude-opus-5 |
| Median latency | 222605 ms | 211436 ms | 11169 ms · codex-cli + gpt-5.6-sol |
| Reliability | 100% | 100% | even |
| Error rate | 0% | 0% | even |
claude-code + claude-opus-5: 64.0% of Claude Max 5x per run, about 1.6 runs per 5h. codex-cli + gpt-5.6-sol: 3.6% of ChatGPT Plus per run, about 27.8 runs per week. Each figure is a share of that agent's own plan, so there is no delta to draw.
Grades and deltas are comparable only within a suite version. See methodology.