STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Claude Opus 5.5 vs Crouton Alpha

Claude Opus 5.5 leads Crouton Alpha by 24.6 points on StealthMark, 72.6 to 48.0. It leads on all 9 benchmarks. Claude Opus 5.5 scores higher on Newton's Mirror, with its largest category advantage in reflections.

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Model guide ↗

Overall StealthMark

72.6/100Overall rank 2/56
48.0/100Overall rank 23/56

General Intelligence

71.3/100
43.5/100

Visual Intelligence

75.0/100
56.0/100

Reasoning efficiency

How many reasoning tokens a model needs for the quality it delivers.

Single-step reasoning How much it reasons to understand a task

Multi-step reasoning How much it keeps reasoning as a task goes on

  • Claude Opus 5.5

Cost efficiency

How much Performance you get for your money.

  • Crouton AlphaNot measured

Open or local

BENCHMARK BY BENCHMARK

Where each model leads

  • Claude Opus 5.5
  • Crouton Alpha
  • Other models
  • Median

DATASHEET

Specs and pricing

  • Claude Opus 5.5
  • Crouton Alpha
  • Other models
  • Median
PricePer 1M output tokens, input below
Claude Opus 5.5: $20$4 inputCrouton Alpha: No list price
Context windowTokens per request, max output below
Claude Opus 5.5: 1M128K max outputCrouton Alpha: Not published
Output speedTokens per second, our measurement
Claude Opus 5.5: 166Tiedtokens/sCrouton Alpha: 175Tiedtokens/s
Developer
AnthropicNot published
Released
22 Sep 2026Not published
Origin
United StatesNot published
Input → output
Text, image → textNot published

Full datasheets, every price and sourceClaude Opus 5.5 ↗

Anticipating threats and planning ahead. Collect coins while avoiding ghosts. Ghosts move before the player each turn, and collisions cost a life. 3 levels in sequence, up to 66 turns in total. Earlier moves and outcomes carry forward, testing learning across levels.

Claude Opus 5.5 66.3/100Rank 5/52

Survived 3 of 3
Foresight: complete playing field
Level 39 ptsTurn 20 / 20

Crouton Alpha 32.3/100Rank 29/52

Survived 1 of 3
Foresight: complete playing field
Level 39 ptsTurn 20 / 20

Points per level

LevelClaude Opus 5.5Crouton Alpha
Level 1Second Thoughts
27 ptsSurvived
3 ptsOut of lives
Level 2Pressure Pot
11 ptsSurvived
7 ptsOut of lives
Level 3Hide or Flight
9 ptsSurvived
9 ptsSurvived

Cooperative planning and learning from experience. Coordinate two robots to push numbered cores onto matching sockets. Pressure plates hold doors open; moving either robot uses one turn. 5 levels in sequence, up to 152 turns in total. Earlier moves and outcomes carry forward, testing learning across levels.

Claude Opus 5.5 87.6/100Rank 1/53

Cleared 5 of 5
Latch: complete playing field
Level 520.6 ptsTurn 27 / 40

Crouton Alpha 59.5/100Rank 24/53

Cleared 4 of 5
Latch: complete playing field
Level 520.2 ptsTurn 29 / 40

Points per level

LevelClaude Opus 5.5Crouton Alpha
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
10.2 ptsClearedFinished early · 1 beacon left
9.4 ptsCleared
Level 3Relay vault
19.2 ptsCleared
11.2 ptsFinished early
Level 4Passing bay
18.2 ptsClearedFinished early · 3 beacons left
18.2 ptsClearedFinished early · 3 beacons left
Level 5Second thoughts
20.6 ptsCleared
20.2 ptsCleared

Newton's Mirror

Same task instructions

Physics, perspective and recursive reflections, tested together. Explore the test ↗

The judgment

Claude Opus 5.5

Open lateral sightlines, first reflected silhouettes and near-field planar panel placement are convincing. Missing outer chains, truncated repetitions and absent nested spherical room and emitter imagery remain the main weaknesses.

Crouton Alpha

The artwork establishes approximate central placement, a separate airborne black blob, and basic wall and floor sphere images. Its defining weaknesses are the largely absent recursive reflection system, missing emitter mappings, satin steel appearance and unresolved paint interaction. The black lateral wedges do not establish a separate viewport, and the hidden floor contact does not establish a gap. The category values remain unchanged.

Score breakdown

CategoryClaude Opus 5.5Crouton Alpha
State at 600 ms24.0/2519.0/25
Camera and placement15.0/1511.0/15
Reflections55.0/12021.5/120
Materials and scale9.0/106.0/10
Floor-damage reward0.0/100.0/10

Benchmark task

A spinning metal sphere and paint in a mirrored room test physical reasoning, perspective and consistency across repeated reflections.

Selfie

Different task instructions

Visual construction and creative interpretation.

The judgment

Claude Opus 5.5

The centered coral squid has a friendly, restrained expression and a balanced radial silhouette within a cream arch. Smooth curves and soft shading give it an appealing matte finish. The mantle is more elongated than compact, the upper arms are visually ambiguous, and the two hanging tentacles read somewhat like legs. Clean execution supports a strong stylized illustration.

Crouton Alpha

A cheerful, readable cartoon captures the crouton's signature expression and many specific accessories. Coherent cube geometry and foreground foreshortening support the selfie. Simple construction and flat material treatment limit its sophistication, while the tipping raft, advancing soup and unnoticed soaking remain insufficiently clear.

Score breakdown

CategoryClaude Opus 5.5Crouton Alpha
Task & likeness8.0/106.5/10
Anatomy & construction7.5/105.5/10
Space & placement8.0/106.5/10
Light & reflections7.5/105.5/10
Purposeful detail7.0/107.0/10
Artistry & character7.0/105.0/10
Materials & effects7.0/105.5/10
Visual integrity8.5/107.5/10

Benchmark task

Claude Opus 5.5

A coral squid with spreading arms tests connected anatomy, balanced composition and soft surface shading.

Crouton Alpha

Character scenes test expression, anatomy, materials and coherent visual construction.

Mona Lisa

Same task instructions

Precise visual recall and portrait reconstruction.

The judgment

Claude Opus 5.5

The portrait preserves the recognizable composition, dark veil, folded hands and distant landscape. Replication is limited by the elongated face and neck, conspicuous eyes and simplified smile. Hands remain connected but their rounded fingers and wrists lack convincing anatomy. Restrained colors create cohesion; shallow modeling and pervasive mottling weaken volume and painterly subtlety.

Crouton Alpha

A recognizable, coherent simplification with readable eyes, a restrained smile and modest facial volume. Frontal symmetry, an oversized head, capsule-like hands and geometric scenery substantially limit likeness, anatomy and depth. Clean contours preserve basic integrity but do not establish sophisticated construction or finish.

Score breakdown

CategoryClaude Opus 5.5Crouton Alpha
Task & likeness6.5/104.5/10
Anatomy & construction5.5/104.0/10
Space & placement6.5/104.5/10
Light & reflections6.5/105.0/10
Purposeful detail6.5/104.0/10
Artistry & character6.0/104.5/10
Materials & effects7.0/104.0/10
Visual integrity7.0/106.0/10

Benchmark task

An SVG interpretation of the Mona Lisa tests facial likeness, anatomy and the composition of a familiar portrait.

Beach

Same task instructions

Creativity, perspective and visual beauty.

The judgment

Claude Opus 5.5

A lively, well-composed beach illustration with rich sunset colors, recognizable animals and appealing accessories. The sun reflection establishes a strong central focus. Clean silhouettes and small details reward inspection, though simplified animal construction, uneven contact shadows and mostly flat materials limit depth and realism.

Crouton Alpha

A colorful, readable sunset beach scene with playful subjects and a clear central reflection. Purposeful equipment and animal details reward inspection, and the principal attachments remain intact. Basic geometric anatomy, mixed viewpoints and sparse directional shadows limit its construction and depth; smooth gradients provide atmosphere with little material differentiation.

Score breakdown

CategoryClaude Opus 5.5Crouton Alpha
Task & likeness8.5/108.5/10
Anatomy & construction7.5/105.0/10
Space & placement7.0/105.5/10
Light & reflections7.5/105.5/10
Purposeful detail7.5/107.0/10
Artistry & character8.0/105.0/10
Materials & effects6.5/105.5/10
Visual integrity8.0/107.0/10

Benchmark task

A busy shoreline at sunset tests scene composition, animal forms and the relationship between light and water reflections.

Ground Truth

Same task instructions

Physical reasoning, light and visual reconstruction.

The judgment

Claude Opus 5.5

This benchmark has not been assessed yet.

Crouton Alpha

This benchmark has not been assessed yet.

Benchmark task

A plank, computer mouse and blueberry in a steel room test physical stability, spatial relationships, materials and lighting.

Raccoon

Same task instructions

Scene composition and interacting subjects.

The judgment

Claude Opus 5.5

The masked raccoon clearly rides the dog's back, and the dog's forward paw reaches the steering grip. Expressive faces, vivid colors and sweeping wakes create an appealing illustration. Connected limbs remain schematic, as does the small steering assembly. The broad hull and flat foam weaken water contact; the glowing sun lacks a corresponding reflection or convincing cast shadows.

Crouton Alpha

A readable cartoon with expressive faces, purposeful markings and clear water motion. Hull shading and an underside shadow establish modest depth. The dog contacts the controls, but the raccoon's frontal pose leaves its seated weight unresolved. Simple anatomy and limited shared perspective constrain the drawing.

Score breakdown

CategoryClaude Opus 5.5Crouton Alpha
Task & likeness8.5/107.0/10
Anatomy & construction7.5/105.0/10
Space & placement7.5/106.0/10
Light & reflections6.0/106.0/10
Purposeful detail8.5/106.5/10
Artistry & character7.0/105.0/10
Materials & effects7.0/105.5/10
Visual integrity8.0/106.0/10

Benchmark task

A jet-ski scene pairs a canine driver with a raccoon passenger. It tests the placement and contact of interacting subjects, along with vehicle construction.

Pelican

Same task instructions

Subject construction and spatial relationships.

The judgment

Claude Opus 5.5

The recognizable pelican, orderly bicycle wheels and harmonious sunset create an appealing illustration. Both legs connect to the body and reach pedals; no clear detached or inverted parts appear. Steering contact and seating support are less convincing, while the drivetrain remains schematic. Crisp outlines give a clean finish, but limited shading and flat surfaces leave the scene with modest depth.

Crouton Alpha

A recognizable, expressive pelican cyclist with purposeful feather and bicycle detail. Readable steering reach, connected machinery and modest body shading earn additional credit. Jointless legs, uncertain pedal engagement and unclear seated support keep the central action only partially resolved; shallow space and simple materials further limit the illustration.

Score breakdown

CategoryClaude Opus 5.5Crouton Alpha
Task & likeness8.5/107.0/10
Anatomy & construction8.0/105.0/10
Space & placement7.0/105.5/10
Light & reflections6.0/105.5/10
Purposeful detail8.0/106.5/10
Artistry & character7.5/105.5/10
Materials & effects6.0/105.0/10
Visual integrity8.5/106.0/10

Benchmark task

A cycling pelican tests anatomy, riding posture and contact between the bird and the bicycle.