SpaceChem Bench: No Employment Record Found

research_6 Hard Fusion Single-reactor Atropos Station Random inputs · SpaceChem Bench report →

Random inputs: α Boron (B) / Aluminum (Al) / Silicon (Si), β Hydrogen (H). Output: ψ Hydrochloric Acid (HCl) ×20. Features: Bonders (2), Sensor, Fuser, Random inputs.

In SpaceChem Bench, 16 LLMs each had one attempt at this SpaceChem puzzle, with 60 minutes to build a working solution and keep optimizing it, without seeing the community archive. 12 of 16 models solved it. Together they found 3 new Pareto-frontier points beyond the frozen community archive.

12 / 16models solved it
425best LLM cycles (333 community)
3new frontier points

Records

ScoreCommunity bestBest LLMModel
Cycles333425GPT-6 Astra · +28%
Reactors11DeepSeek V4.1 Flash Ties record
Symbols1220GPT-6 Astra · +67%

Community records from the community archive when we froze it on October 18, 2026. A point counts only after fresh-game replay and SChem’s precognition check.

Pareto frontier

Pareto explorer

Lower is better ↙
Loading interactive Pareto explorer…
Community archiveModel frontier pointNew frontier point
Select a point with the mouse or keyboard to inspect its scores and reactor blueprint.

Search over time

Loading puzzle trajectories…

Every model

ModelSolvedBest cyclesBest reactorsBest symbolsNew frontier points
01Opus 5.5Yes4251213
02Sonnet 5.5Yes4641222
03GPT-6 AstraYes4251201
04Gemini 4 ArgonYes467123—
05Fable 5.1Yes584122—
06GPT-6.1 SolYes693120—
07Gemini 3.8 FlashYes1,230132—
08Kimi K3.1 ProYes1,467133—
09DeepSeek V4.1 FlashYes1,491137—
10Haiku 5.5Yes1,735130—
11Grok 4.7Yes1,801157—
12Muse Spark 1.3Yes2,177146—
13GLM-5.3No————
14GPT-6 LunaNo————
15MiMo-V2.6-ProNo————
16Muse Wonder 1.0No————

Best scores can come from different solutions. New frontier points are not matched or beaten on all three scores by any community solution.

Best model solutions

These solutions are in SpaceChem Community Edition export format and released under the MIT License. All of this puzzle’s model solutions are on GitHub and Hugging Face.

Opus 5.5 Fewest cyclesFewest reactors

425 cycles · 1 reactor · 25 symbolsresearch_6.425-1-25.txt on GitHub

Layout

α β ψ ω 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 ↓ → ← ↓ ↑ → ↑ → ← ↓ ← S↑ S↑ GRAB IN α DROP FUSE ?Cl← ?Cl↑ B+ GRAB IN β DROP OUT ψ IN β IN β IN β

Running in the game

Opus 5.5 solution running on research_6 in SpaceChem
SpaceChem Community Edition export (research_6.425-1-25.txt)
SOLUTION:No Employment Record Found,Player,0-0-0
COMPONENT:'drag-advancedfusion-reactor',2,0,''
MEMBER:'instr-start',-90,0,32,1,4,0,0
MEMBER:'instr-start',-90,0,128,2,2,0,0
MEMBER:'feature-bonder',-1,0,1,2,3,0,0
MEMBER:'feature-bonder',-1,0,1,1,3,0,0
MEMBER:'feature-sensor',-1,0,1,2,4,0,0
MEMBER:'feature-fuser',-1,0,1,1,5,0,0
MEMBER:'instr-arrow',90,0,64,1,1,0,0
MEMBER:'instr-arrow',0,0,64,1,4,0,0
MEMBER:'instr-arrow',180,0,64,2,1,0,0
MEMBER:'instr-arrow',90,0,64,2,4,0,0
MEMBER:'instr-arrow',-90,0,64,2,5,0,0
MEMBER:'instr-grab',-1,1,128,1,1,0,0
MEMBER:'instr-input',-1,0,128,2,1,0,0
MEMBER:'instr-grab',-1,2,128,2,3,0,0
MEMBER:'instr-fuse',-1,0,128,2,5,0,0
MEMBER:'instr-sensor',-90,0,128,2,4,0,17
MEMBER:'instr-arrow',0,0,16,1,3,0,0
MEMBER:'instr-arrow',-90,0,16,1,5,0,0
MEMBER:'instr-arrow',0,0,16,2,5,0,0
MEMBER:'instr-arrow',180,0,16,3,5,0,0
MEMBER:'instr-arrow',90,0,16,6,3,0,0
MEMBER:'instr-arrow',180,0,16,6,5,0,0
MEMBER:'instr-bond',-1,0,32,1,3,0,0
MEMBER:'instr-grab',-1,1,32,1,5,0,0
MEMBER:'instr-input',-1,1,32,3,5,0,0
MEMBER:'instr-grab',-1,2,32,6,3,0,0
MEMBER:'instr-output',-1,0,32,6,4,0,0
MEMBER:'instr-sensor',180,0,32,2,5,0,17
MEMBER:'instr-input',-1,1,32,4,3,0,0
MEMBER:'instr-input',-1,1,32,6,5,0,0
MEMBER:'instr-input',-1,1,32,5,5,0,0

GPT-6.1 Sol Fewest symbols

771 cycles · 1 reactor · 20 symbolsresearch_6.771-1-20.txt on GitHub

Layout

α β ψ ω 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 ↓ → → ↓ → ← ← ← ↑ ↓ ↑ S← S↑ IN α GRAB IN β B+ ?Cl↓ OUT ψ DROP FUSE G/D

Running in the game

GPT-6.1 Sol solution running on research_6 in SpaceChem
SpaceChem Community Edition export (research_6.771-1-20.txt)
SOLUTION:No Employment Record Found,Player,0-0-0
COMPONENT:'drag-advancedfusion-reactor',2,0,''
MEMBER:'instr-start',180,0,128,2,0,0,0
MEMBER:'instr-start',-90,0,32,1,6,0,0
MEMBER:'feature-bonder',-1,0,1,1,5,0,0
MEMBER:'feature-bonder',-1,0,1,2,5,0,0
MEMBER:'feature-sensor',-1,0,1,3,4,0,0
MEMBER:'feature-fuser',-1,0,1,1,4,0,0
MEMBER:'instr-arrow',90,0,64,1,0,0,0
MEMBER:'instr-arrow',0,0,64,1,4,0,0
MEMBER:'instr-arrow',0,0,64,2,4,0,0
MEMBER:'instr-arrow',90,0,64,2,5,0,0
MEMBER:'instr-arrow',0,0,64,2,6,0,0
MEMBER:'instr-arrow',180,0,64,3,4,0,0
MEMBER:'instr-arrow',180,0,64,3,5,0,0
MEMBER:'instr-arrow',180,0,64,7,0,0,0
MEMBER:'instr-arrow',-90,0,64,7,6,0,0
MEMBER:'instr-input',-1,0,128,1,0,0,0
MEMBER:'instr-grab',-1,1,128,1,1,0,0
MEMBER:'instr-input',-1,1,128,2,4,0,0
MEMBER:'instr-bond',-1,0,128,2,5,0,0
MEMBER:'instr-sensor',90,0,128,3,4,0,17
MEMBER:'instr-output',-1,0,128,7,2,0,0
MEMBER:'instr-grab',-1,2,128,7,3,0,0
MEMBER:'instr-arrow',90,0,16,1,4,0,0
MEMBER:'instr-arrow',-90,0,16,1,5,0,0
MEMBER:'instr-fuse',-1,0,32,1,4,0,0
MEMBER:'instr-grab',-1,0,32,1,5,0,0