Inverse IFEval
Models follow 1,012 Chinese and English instructions that conflict with habits learned in fine-tuning, such as writing code without comments. A model judge scores compliance.
Eight challenge types across 23 domains. It is a different test from IFEval.
- Made by
- ByteDance Seed and collaborators (Zhang et al.)
- Released
- September 2025
- Kind
- Following precise instructions
- Level
- Everyday
- Scored
- Graded by a model
- Answers
- Open-ended
- Last in a launch post
- October 2026, dropped before it saturated
- Last model added
- October 2026
In the authors’ words
Large Language Models (LLMs) achieve strong performance on diverse tasks but often exhibit cognitive inertia, struggling to follow instructions that conflict with the standardized patterns learned during supervised fine-tuning (SFT). To evaluate this limitation, we propose Inverse IFEval, a benchmark that measures models Counter-intuitive Abilitytheir capacity to override training-induced biases and comply with adversarial instructions. Inverse IFEval introduces eight types of such challenges, including Question Correction, Intentional Textual Flaws, Code without Comments, and Counterfactual Answering. Using a human-in-the-loop pipeline, we construct a dataset of 1012 high-quality Chinese and English questions across 23 domains, evaluated under an optimized LLM-as-a-Judge framework. Experiments on existing leading LLMs demonstrate the necessity of our proposed Inverse IFEval benchmark. Our findings emphasize that future alignment efforts should not only pursue fluency and factual correctness but also account for adaptability under unconventional contexts. We hope that Inverse IFEval serves as both a diagnostic tool and a foundation for developing methods that mitigate cognitive inertia, reduce overfitting to narrow patterns, and ultimately enhance the instruction-following reliability of LLMs in diverse and unpredictable real-world scenarios.
Seed1.8 leads with 80.3%
Best score per model as labs report them in their own cards. Labs pick their own settings, so these compare less cleanly than independent runs.
- 1
Seed1.8 80.3%
- 2
Seed2.0 Pro 78.9%
- 3
Nemotron 3.5 Bolt E4B 45.3%
Source: Labs’ model cards
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | | 80.3% | Dec 2025 | Lab model card | |
| 2 | | 78.9% | Feb 2026 | Lab model card | |
| 3 | | 45.3% | Oct 2026 | Lab model card |
Number one over time
Lab claims count from the day the card came out, independent runs from the model’s release.
Source: Labs’ model cards
Scores over time
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Source: Labs’ model cards
Labs headline it less often now, last in October 2026
Launch posts from every lab that has listed it, one tick per post. Tall colored ticks include it, and short gray ones leave it out.
| Date | Launch post | Score | As the post writes it |
|---|---|---|---|
| Oct 23, 2026 | 45.3 | InverseIFEval | |
| Feb 14, 2026 | 78.9 | Inverse IFEval | |
| Dec 18, 2025 | 80.3 | Inverse IFEval |
3 system cards report it, from 2 labs
Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.
| Date | Document | Score | As the document writes it | Section |
|---|---|---|---|---|
| Oct 23, 2026 | | 45.3 | InverseIFEval, released Q4_K_M imatrix checkpoint (Table 5). BF16 46.84 (Table 3) | Capabilities |
| Mar 21, 2026 | | 80.3 | Inverse IFEval (Table 1) | Capabilities |
| Feb 14, 2026 | | 78.9 | Inverse IFEval (Table 3) | Capabilities |
More in Instructions and chat
- IFEval In use Models answer about 500 prompts containing verifiable instructions such as word limits or required keywords. Code checks each instruction for strict and loose accuracy.
Gemma 4 31B IT 98.9%
- IFBench In use 58 new out-of-domain verifiable output constraints. Scored by programmatic constraint checks (strict or loose).
Nemotron-Cascade 2 30B-A3B 82.9%
- MultiChallenge In use Multi-turn conversations testing instruction retention, inference memory, versioned editing and self-coherence. Graded by LLM judge with rubrics. GPT-6.1 Sol 82%
- Multi-IF In use Models follow verifiable instructions over three-turn conversations in eight languages, extending IFEval. Scored by instruction accuracy at each turn. LFM3-1.7B 89.1%
- AdvancedIF In use Models respond to over 1,600 prompts with complex, multi-turn, and system-level instructions. A judge model checks each response against expert-written rubrics.
MAI-Thinking-1 85%
- IFStruct In use Models generate JSON or YAML that must follow a requested schema and phrasing constraints, without constrained decoding. A response passes only if every structural constraint holds.
Gemma 4 31B IT 95.9%