STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Claude Fable 5.1 vs GPT 5.6 Terra

Claude Fable 5.1 scores 11.0 points higher overall (62.1 vs 51.1). Claude Fable 5.1 scores higher on Newton's Mirror, with its largest category advantage in reflections.

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Overall StealthMark

62.1/100
51.1/100

General Intelligence

54.3/100
31.1/100

Visual Intelligence

67.7/100
66.2/100

Newton's Mirror

Same prompt

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

Claude Fable 5.151.7/100

Claude Fable 5.1: Newton's Mirror SVG benchmark
Researcher observations

The broad paint sequence, bilateral near-field sphere arrangement, overlaps and diminishing panel repetitions are recognizable; crimson is slightly too low. Small paint scale and basic shading provide material cues, although the steel response remains soft. Inaccurate light projections, missing outer chains and incomplete nested room imagery remain the principal limitations.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

GPT 5.6 Terra23.3/100

GPT 5.6 Terra: Newton's Mirror SVG benchmark
Researcher observations

The real sphere and airborne black blob are substantially too low in the complete frame after accounting for aspect ratio. The first wall and floor reflections have incompatible placement, relative size or silhouette. Both lateral regions lack the references' receding lane-and-chain organization. The few recognizable mirror images provide limited optical structure. The main, side and floor spheres replace nested mirror imagery with smooth bands, while sparse planar light patches and broad spherical highlights fail to establish coherent repeated emitter mapping.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

Compare category scores
CategoryClaude Fable 5.1GPT 5.6 Terra
State at 600 ms24.0/2523.5/25
Camera and placement14.0/156.0/15
Reflections48.0/1207.0/120
Materials and scale7.0/105.5/10
Floor-damage reward0.0/100.0/10

Selfie

Different prompts

Claude Fable 5.169.0/100

Claude Fable 5.1: Selfie SVG benchmark
Researcher observations

The coral palette, friendly face, matte shading and cream arch create a coherent emblem. However, the mantle is elongated rather than compact, and the appendages spread mostly sideways and downward instead of forming an evenly spaced, flower-like starburst. Two thin hanging appendages weaken the thick-arm motif. Clean contours and balanced framing support the simple design.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

GPT 5.6 Terra73.0/100

GPT 5.6 Terra: Selfie SVG benchmark
Researcher observations

Six ivory heads and rounded lobes create a striking radial emblem around a clear hexagonal opening. Soft shading gives the bodies volume, but abrupt rectangular and diagonal band endings make the continuous alternating weave ambiguous. Repetitive scale lines and simplified faces convey an ornamental serpent more convincingly than living anatomy.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

Compare category scores
CategoryClaude Fable 5.1GPT 5.6 Terra
Prompt & likeness6.5/107.5/10
Anatomy & construction6.5/106.5/10
Space & placement7.5/107.5/10
Light & reflections6.5/107.5/10
Purposeful detail6.0/107.0/10
Artistry & character7.5/108.0/10
Materials & effects6.5/107.0/10
Visual integrity8.0/107.5/10

Beach

Same prompt

Claude Fable 5.175.0/100

Claude Fable 5.1: Beach SVG benchmark
Researcher observations

The colorful sunset, layered shoreline, animals, kite and beach toys fulfill the lively beach brief. Clean silhouettes and a balanced composition give the illustration character. Construction is simplified: the umbrella resembles a segmented fan, dolphins have weak water interaction, and the sun’s reflection forms a rigid widening wedge. Flat surfaces and sparse contact shadows limit depth.

Exact prompt

Create an SVG of a amazing beach scene. Sunset, animals, fun, birds, reflections Make it a masterpiece, no tools allowed

GPT 5.6 Terra73.3/100

GPT 5.6 Terra: Beach SVG benchmark
Researcher observations

Warm sunset gradients, framing palms and colorful beach activities create an appealing scene. Animals, birds and a sun reflection fulfill the brief. The dog and turtle remain schematic, foreground depth is shallow, and the reflection forms rigid bands. Clean silhouettes and readable accessories support a competent illustration, but limited anatomy, material variation and lighting keep it below exceptional.

Exact prompt

Create an SVG of a amazing beach scene. Sunset, animals, fun, birds, reflections Make it a masterpiece, no tools allowed

Compare category scores
CategoryClaude Fable 5.1GPT 5.6 Terra
Prompt & likeness8.5/108.5/10
Anatomy & construction7.0/107.0/10
Space & placement7.0/107.0/10
Light & reflections7.0/106.5/10
Purposeful detail7.5/107.0/10
Artistry & character8.0/107.5/10
Materials & effects6.5/106.5/10
Visual integrity8.0/108.0/10

Mona Lisa

Same prompt

Claude Fable 5.156.5/100

Claude Fable 5.1: Mona Lisa SVG benchmark
Researcher observations

The dark clothing, crossed hands and hazy landscape establish the Mona Lisa composition. Replication is limited by the frontal, elongated face, wide eyes and simplified smile. Rounded, parallel fingers and unclear wrist transitions weaken the hands. Warm facial shading gives some volume, but broad garment shapes and scattered crack marks substitute for convincing folds and painterly detail.

Exact prompt

Replicate mona-lisa as SVG Make it a masterpiece, no tools allowed

GPT 5.6 Terra49.5/100

GPT 5.6 Terra: Mona Lisa SVG benchmark
Researcher observations

The dark clothing, central portrait and restrained smile evoke the Mona Lisa, but replication is limited by the broad face, elongated neck, nearly frontal pose and indistinct landscape. Soft gradients give the face some volume. Crossed arms become rounded masses without readable fingers or wrists, and the expression lacks the original's subtlety. Clean framing and curves support an otherwise basic, uneven portrait.

Exact prompt

Replicate mona-lisa as SVG Make it a masterpiece, no tools allowed

Compare category scores
CategoryClaude Fable 5.1GPT 5.6 Terra
Prompt & likeness6.0/105.0/10
Anatomy & construction5.0/104.0/10
Space & placement6.0/105.5/10
Light & reflections6.0/106.0/10
Purposeful detail5.0/103.5/10
Artistry & character5.5/105.0/10
Materials & effects5.5/104.5/10
Visual integrity6.5/106.5/10

Raccoon

Same prompt

Claude Fable 5.170.8/100

Claude Fable 5.1: Raccoon SVG benchmark
Researcher observations

The raccoon rides on the dog's back, and the dog's extended foreleg reaches the jet ski controls. Expressive faces, a clear silhouette and sweeping spray make the action readable. Limb and handlebar overlaps weaken construction; broad shading provides limited volume, and the glowing sun has little corresponding reflection on the water. Clean vector shapes support an appealing but simplified illustration.

Exact prompt

Generate an SVG: A raccoon sits on a dog's back while the dog steers a jet ski Make it a masterpiece, no tools allowed

GPT 5.6 Terra72.0/100

GPT 5.6 Terra: Raccoon SVG benchmark
Researcher observations

Expressive faces, a recognizable raccoon perched on the dog, and a sweeping wake make an appealing cartoon. The principal weakness is the steering interaction: the dog's paw sits beside the control assembly without a convincing handlebar grip. Bold outlines and coherent layering provide polish, while simplified shading, compressed seating geometry and angular splashes limit depth and physical credibility.

Exact prompt

Generate an SVG: A raccoon sits on a dog's back while the dog steers a jet ski Make it a masterpiece, no tools allowed

Compare category scores
CategoryClaude Fable 5.1GPT 5.6 Terra
Prompt & likeness8.5/107.5/10
Anatomy & construction6.5/106.0/10
Space & placement7.0/107.5/10
Light & reflections5.5/106.5/10
Purposeful detail7.0/107.5/10
Artistry & character7.5/108.0/10
Materials & effects6.5/107.0/10
Visual integrity7.5/108.0/10

Pelican

Benchmax control

Outside General and Visual Intelligence.

Claude Fable 5.172.3/100

Claude Fable 5.1: Pelican SVG benchmark
Researcher observations

The pelican reads clearly, with an expressive face, prominent bill and appealing composition. Both legs connect to the body, but the far foot's pedal contact and the wing's steering grip remain unclear. Wheel alignment and background layers are coherent. Clean contours and feather lines give polish, while schematic machinery, limited surface texture and weak directional lighting constrain the finish.

Exact prompt

Generate an SVG of a pelican riding a bicycle Make it a masterpiece, no tools allowed

GPT 5.6 Terra70.5/100

GPT 5.6 Terra: Pelican SVG benchmark
Researcher observations

The oversized bill, expressive eye and balanced twilight palette make the cyclist immediately readable. Clean contours and wheel details support the illustration, but the rabbit-like head tufts weaken pelican likeness. The wing does not clearly grip the handlebar, pedal contact is uneven, and the drivetrain is incomplete. Lighting remains mostly decorative.

Exact prompt

Generate an SVG of a pelican riding a bicycle Make it a masterpiece, no tools allowed

Compare category scores
CategoryClaude Fable 5.1GPT 5.6 Terra
Prompt & likeness8.5/108.0/10
Anatomy & construction6.5/106.0/10
Space & placement7.5/107.0/10
Light & reflections6.0/106.5/10
Purposeful detail7.0/107.0/10
Artistry & character7.5/107.5/10
Materials & effects6.0/106.5/10
Visual integrity8.0/108.0/10