Agnes 3.0 Flash vs GPT-5.3 Codex
Agnes 3.0 Flash 
GPT-5.3 Codex Verdict
- GPT-5.3 Codex (xhigh) leads on quality: 65.4 vs 62.3.
- Agnes 3.0 Flash is stronger in composite.
- GPT-5.3 Codex (xhigh) is stronger in agents & tools, knowledge, long context, reasoning, coding, instruction following, multimodal.
- Agnes 3.0 Flash is 64× cheaper ($0.075 vs $4.81 per 1M blended).
| Metric | Agnes 3.0 Flash | GPT-5.3 Codex (xhigh) |
|---|---|---|
| BenchLeader Index | 62.3 | 65.4 |
| Agents & tools score | 76.8 | 79.8 |
| Composite score | 74.0 | 70.2 |
| Knowledge score | 59.1 | 69.4 |
| Long context score | 67.0 | 68.2 |
| Reasoning score | 71.1 | 74.4 |
| Coding score | – | 61.7 |
| Instruction following score | – | 73.4 |
| Multimodal score | – | 63.0 |
| Blended price $/M | $0.075 | $4.81 |
| Output speed | – | 125 tok/s |
| Time to first answer | – | 50.8 s |
| Context window | 1M | 400k |
| WeirdML | – | 77.9% |
| AA Intelligence Index | 35.5 | 32.5 |
| IFBench | – | 75.4% |
| AA-LCR | 81.0% | 83.3% |
| MMMU-Pro | – | 78.5% |
| AA-Omniscience | -10.6 | 10.9 |
| Terminal-Bench Hard | – | 53.0% |
| GPQA Diamond (AA) | 92.4% | 91.5% |
| Humanity's Last Exam (AA) | 38.5% | 42.5% |
| SciCode (AA) | 51.6% | – |
| τ²-Bench Telecom (AA) | – | 86.0% |
| LiveCodeBench | – | 87.3% |
| IOI | – | 53.8% |
| SWE-bench (Vals) | – | 78.0% |
| CritPt | 15.1% | 16.9% |
| GDPval (AA) | 53.7% | – |
| τ²-Bench Banking (AA) | 47.6% | – |
| Vibe Code Bench v1.1 | – | 61.8% |
| ALE-Bench | – | 1655.2 |
Data as of 2026-09-19. Best configuration of each model; every score links to its source on the model pages.
Agnes 3.0 Flash vs GPT-5.3 Codex: questions
- Is Agnes 3.0 Flash better than GPT-5.3 Codex?
- GPT-5.3 Codex (xhigh) leads on quality: 65.4 vs 62.3. The BenchLeader Index combines every independent quality benchmark; GPT-5.3 Codex (xhigh) is ahead overall as of 2026-09-19, but check the category scores for your use.
- Is Agnes 3.0 Flash better than GPT-5.3 Codex for agentic tasks?
- GPT-5.3 Codex scores higher in agentic tasks (80 vs 77 on the category index, where 50 is average).
- Which is cheaper, Agnes 3.0 Flash or GPT-5.3 Codex?
- Agnes 3.0 Flash is cheaper: $0.075 against $4.81 per million tokens, blended at three input tokens per output token.
- Which has the larger context window?
- Agnes 3.0 Flash accepts more context: 1M against 400k tokens.