Oral at three NeurIPS 2026 workshops: NEmo, VLM4RWD, BabyVLM

MindTopo Can Foundation Models Reason in Topological Space?

Models can recognize topological relations in static scenes, but struggle to maintain or act on them reliably across a sequence of actions.

Yunfei Ge1*Anbang Liu1*Qineng Wang1*†Johnalbert Garnica1*Jianwen Lyu1Zihan Wang1Reuben Tan2Jianfeng Gao2Ruohan Zhang1,3Yining Hong3Jiajun Wu3Manling Li1

1Northwestern University2Microsoft Research3Stanford University *Equal contribution · †Project lead

topological properties
5
cognitive levels
2
procedural tasks
13
Core instances
3,900
MLLMs evaluated
13
video generators probed
7

The Extended Set adds 8,780 instances with no exact-input overlap with the Core Set. Explore both sets and download the manifests.

03Play the benchmark

Try the planning environments

These demos run MindTopo's own engines on input-hash-verified boards selected directly from the Core manifest. Core Easy and Core Hard use the same instances, rules, initial states, and action budgets as the primary evaluation.

Loading the gym…

Reasoning examples · reference scores on Core Easy

2D Maze

Continuity
2D Maze example scene

Which points are connected to point A?

View full-size images Scene

Humans 98%Best model 99%

3D Maze

Continuity
3D Maze example scene

Which points are connected to point E?

View full-size images Scene

Humans 95%Best model 87%

Assembly

Separation
Assembly example scene

Which pair of subassemblies exactly reconstructs the complete object? Choose A, B, C, D, or E.

Core Easy example

View full-size images Scene Option AOption BOption COption DOption E

Humans 83%Best model 75%

Bead

Order
Bead example scene

Start at the bead circled in white, follow the indicated direction along the string, and list all bead colours in order.

Core Easy example

View full-size images Scene

Humans 93%Best model 52%

Origami Point

Order
Origami Point State 1Origami Point State 14

Track the marked point from state 1 to state 14 of the fold.

View full-size images State 1State 14

Humans 96%Best model 83%

Sheep

Enclosure
Sheep example scene

How many sheep cannot escape to the outside?

View full-size images Scene

Humans 96%Best model 59%

Hole

Enclosure
Hole example scene

How many holes are visible in the top board?

View full-size images Scene

Humans 100%Best model 67%

Knots

Knots
Knots example scene

Which type is this scene?

View full-size images Scene

Humans 92%Best model 89%

04The action gap

Planning lags behind topology recognition

Results on the 3,900-instance Core Set: reasoning accuracy against planning success for every model. Across the evaluated models, identifying topological relations is more successful than acting on them. All Core combines 150 Easy and 150 Hard instances per task. Extended results are reported separately.

Difficulty

13 of 13 models plan worse than they reason

Averages over 8 reasoning and 5 planning tasks. GPT-6 Astra drops from 59.5% to 49.8%; no open-weight model plans above 0.6%.

GPT-6 Astra −9.7
GPT-5.6-Sol −4.5
Claude-Haiku-5.5 −14.5
Gemini-3.1-Pro −15.0
GPT-5.5 −10.6
Gemini-3.1-Flash-Lite −8.8
GPT-5.4-mini −6.6
Llama-4-Maverickopen −6.4
Qwen3.5-397Bopen −6.4
InternVL3.5-241Bopen −6.5
Ministral-3-14Bopen −5.6
Nemotron-Nano-12Bopen −5.4
Gemma-4-31Bopen −3.9
Random chance −7.4
Show data table

Full leaderboard

Select a column to sort.

Average ContinuitySeparationOrderEnclosureKnots
GPT-6 Astra 59.549.870.781.354.771.070.753.369.351.335.333.351.762.020.7
GPT-5.6-Sol 24.319.833.014.011.036.09.318.79.740.331.326.335.325.33.0
Claude-Haiku-5.5 19.95.41.013.30.030.00.011.04.30.042.325.322.031.75.0
Gemini-3.1-Pro 19.24.210.714.00.027.00.06.03.01.030.320.713.741.76.3
GPT-5.5 18.68.08.77.70.033.00.07.310.319.723.727.312.730.77.7
Gemini-3.1-Flash-Lite 9.40.76.71.30.024.30.06.32.70.014.31.70.318.03.0
GPT-5.4-mini 7.30.77.72.70.022.70.05.32.30.05.00.30.012.33.3
Llama-4-Maverickopen 6.90.58.03.70.024.00.04.73.00.02.00.00.010.02.7
Qwen3.5-397Bopen 6.60.26.74.70.022.30.04.71.30.00.31.70.711.00.3
InternVL3.5-241Bopen 6.50.02.03.30.020.30.03.03.70.04.30.30.014.70.0
Ministral-3-14Bopen 6.20.65.02.00.024.00.07.01.70.01.30.00.08.73.0
Nemotron-Nano-12Bopen 5.60.14.01.30.021.70.02.70.30.03.30.30.011.00.7
Gemma-4-31Bopen 4.30.42.33.30.013.00.00.00.00.07.00.01.38.70.7
Random chance 7.90.54.33.70.020.00.07.12.20.05.56.70.014.02.7

05Core & Extended

Core and Extended are evaluated separately

Core is the balanced primary evaluation set. Extended adds exact-input-disjoint instances from the same generators. Scores from the two sets are reported separately and are never pooled.

Core Set

3,900

13 tasks, each with 150 Easy and 150 Hard instances. In total, 2,400 reasoning questions and 1,500 planning episodes.

13-model Core leaderboard · Core manifest (.jsonl.gz)

Extended Set

8,780

Additional instances after removing 2,250 Core overlaps and 5 repeated Swap inputs from the original pool.

11-model Extended results · Extended manifest (.jsonl.gz)

Paper and release files

Current manuscript (PDF) · Composition and deduplication record · Extended result counts (JSON)

The manifests identify each input, its source location, and its content hash. Use them with the benchmark source files to select the evaluation instances; the manifests do not contain the full inputs or rendered images.

arXiv v1 and the Hugging Face snapshot describe earlier dataset compositions. The current manuscript and manifests above define the Core / Extended split used on this page.

Per-task composition of both sets
Evaluation instances per task
TaskCoreExtended
2D Maze300850
3D Maze300846
Pipe300450
Assembly300890
One Stroke300450
Bead300850
Origami Point3001,000
Swap300445
Sheep300700
Hole300699
Chat Noir300450
Knots300850
Untangle300300
Total3,9008,780
Extended results for 11 models

Percent correct or successful. Reason and Plan are unweighted means over the eight reasoning and five planning tasks. Coverage follows the manuscript's Extended table, which excludes GPT-6 Astra and Claude-Haiku-5.5.

Extended Set performance (%)
ModelReasonPlan2D Maze3D MazePipeAssemblyOne StrokeBeadOrigami PointSwapSheepHoleChat NoirKnotsUntangle
GPT-5.6-Sol73.3959.7788.7170.9260.0060.6741.1164.7177.0086.7478.2980.1170.6766.7140.33
GPT-5.560.9330.0067.2951.182.8957.4213.1139.8860.0050.1167.2979.5439.5664.8244.33
Gemini-3.1-Pro58.8826.2736.1258.277.3353.824.4451.8841.1022.4778.4376.1145.1175.2952.00
Gemini-3.1-Flash-Lite45.4811.3633.7636.050.0045.730.0039.7642.2011.6963.1431.628.4471.5336.67
Qwen3.5-397B-A17B30.367.8314.0038.650.0044.830.0021.8842.6012.369.4334.9111.7836.5915.00
GPT-5.4-mini26.7213.3417.5322.340.2236.180.0032.4727.2013.7125.7123.758.4428.5944.33
InternVL3.5-241B22.912.8617.1811.820.0012.700.0027.2919.505.6222.8622.031.3349.887.33
Llama-4-Maverick-17B-128E22.824.5125.6517.970.0035.730.0030.9417.107.4215.573.722.4435.8812.67
Ministral-3-14B-Instruct-251220.986.2320.3512.410.0028.760.0016.4718.405.1716.297.305.3347.8820.67
Nemotron-Nano-12B-VL-v220.081.5614.1211.820.0028.880.0020.4726.701.5720.439.870.2228.356.00
Gemma-4-31B-IT11.837.6730.3518.680.0019.100.009.411.601.359.290.0017.336.2419.67

Scroll sideways to see every task.

06Against humans

Even the strongest model trails humans on most tasks

Easy level, where five professional annotators solved the same instances under the same instructions (inter-annotator agreement 0.89).

Compare humans with
Radar chart of per-task scores on the Easy level for humans and the selected model. 255075100 ●2D Maze ●3D Maze ●Pipe ●Assembly ●One Stroke ●Bead ●Origami Point ●Swap ●Sheep ●Hole ●Chat Noir ●Knots ●Untangle

Reasoning avg

76.3 vs 94.2

-17.9 pts from humans

Planning avg

81.9 vs 99.9

-18.0 pts from humans

Largest gaps to humans

  1. Untangle −82.0
  2. Bead −41.0
  3. Sheep −37.0
  4. Hole −32.9

GPT-6 Astra reaches human level (within 1 point) on 2D Maze, Pipe, Swap.

Show data table

07Training

Training teaches visual patterns, not plans

Qwen3-VL-2B-Instruct trained on the Easy level of each task. Answer supervision lifts reasoning sharply; planning success barely moves, and gains on held-out tasks are uneven.

Single-task runs split Easy data into 80% training, 10% validation, and 10% test. Planning predicts a complete action sequence from the initial observation and executes it without further model feedback. Bead uses a simplified variant. These test scores use a different protocol from the Core leaderboard's closed-loop evaluation.

Training method

Reasoning avg (5 tasks)

14.2% 51.5%

+37.3 pts

Planning avg (4 tasks)

0.2% 6.3%

+6.1 pts

Reasoning tasks

2D Maze not evaluated 13.5 +4.3
Knots not evaluated 79.6 +68.4
Assembly not evaluated 53.4 +21.3
Bead not evaluated 53.0 +43.6
Sheep not evaluated 58.2 +48.8

Planning tasks

One Stroke not evaluated 0.5 +0.5
Untangle not evaluated 17.4 +16.6
Pipe not evaluated 0.0 +0.0
Swap not evaluated 7.4 +7.4
Show data table

08Failure modes

Reasoning fails at seeing. Planning fails at acting.

910 failures of Gemini-3.1-Pro and InternVL3.5-241B, sampled uniformly and labeled with the earliest stage that explains them, from following the instruction to planning the action.

Model

Reasoning n = 560

33.8%5.9%47.5%1.4%11.4%0.0%0.0%

Planning n = 350

12.9%14.3%22.0%0.0%10.6%14.9%25.4%
Show data table

09Visual imagination

Solved endpoints do not certify valid rollouts

Can image or video generation act as the world model that planning lacks? We let generators render the next state, or a whole plan, and then check sampled states and transitions.

Probing uses 105 episodes per task, 35 from each of three generator difficulty settings, including instances outside the Core levels. The video verifier uses a separate sample of 1,890 rollouts. It parses 41 evenly spaced frames, checks static constraints on four frames and dynamics between adjacent sampled frames, and requires every check to pass. Its human validation mainly confirms rejections; it is a strict screen for invalid rollouts.

35.2%

best rate of a solved final frame (LTX-2.5, Pipe)

0.0%

of 1,890 audited rollouts pass all process-validity checks on sampled frames and transitions

Manual audit of 119 Wan2.2-I2V-A14B rollouts

Illegal dynamics 116/119
Topology broken 93/119
Inconsistent frames 90/119

A generated next frame helps only where a local cue suffices

Planner
Knots +31.1
Sheep +38.2
2D Maze +39.7
Untangle +5.7
One Stroke −2.9
Pipe −9.5
Show data table

Manual audit of 464 GPT-Image-2 frames

Illegal dynamics 95/464
Topology broken 92/464
Inconsistent frames 68/464

A solved last frame is not a solved task

One Stroke

LTX-2.3 0.0 0.0
LTX-2.5 0.0 0.0
Veo-3.1-Lite 0.0 0.0
Wan2.2-I2V-A14B 0.0 0.0
MiniMax-H3 0.0 0.0
Seedance-2.5 0.0 0.0

Pipe

LTX-2.3 3.8 0.0
LTX-2.5 35.2 0.0
Veo-3.1-Lite 5.7 0.0
Wan2.2-I2V-A14B 13.3 0.0
MiniMax-H3 19.0 0.0
Seedance-2.5 16.2 0.0

Untangle

LTX-2.3 32.4 0.0
LTX-2.5 6.7 0.0
Veo-3.1-Lite 1.0 0.0
Wan2.2-I2V-A14B 2.9 0.0
MiniMax-H3 5.7 0.0
Seedance-2.5 3.8 0.0

10Citation

Cite MindTopo

@article{ge2026mindtopo,
  title   = {MindTopo: Can Foundation Models Reason in Topological Space?},
  author  = {Yunfei Ge and Anbang Liu and Qineng Wang and Johnalbert Garnica and Jianwen Lyu and Zihan Wang and Reuben Tan and Jianfeng Gao and Ruohan Zhang and Yining Hong and Jiajun Wu and Manling Li},
  journal = {arXiv preprint arXiv:2609.11900},
  year    = {2026},
  url     = {https://mind-topo.github.io/},
}