System Analysis // Reference ID: 294-C

Anthropic: Claude Fable 5.1
vs the field

A forensic evaluation of today's LLM leaderboard. We pressure-test reasoning density, coding, and instruction adherence across five Tier-1 AI models — pulled live from the same aggregated feed the homepage uses.

The contenders

Primary Subject

Anthropic: Claude Fable 5.1

State of the ArtAnthropictextimagefile

Claude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work: long code refactors, front-end and visual...

Contender 02 · Google

Google: Gemini 4 Argon

Arena Elo1638
Contender 03 · xAI

SpaceXAI: Grok 4.7

Arena Elo1634
Contender 04 · Meta

Meta: Muse Wonder

Arena Elo1629
Contender 05 · Moonshot

MoonshotAI: Kimi K3

Arena Elo1621

Cross-Model Capability Matrix

v2.04.14

Best value in each row highlighted in accent. Blank cells mean the provider hasn't reported that benchmark yet.

BenchmarkAnthropic: Claude Fable 5.1Google: Gemini 4 ArgonSpaceXAI: Grok 4.7Meta: Muse WonderMoonshotAI: Kimi K3
Arena Elo
Human blind-vote Elo from LMArena — the closest proxy to 'which model feels smarter'.
16441638163416291621
AA Index
Artificial Analysis' composite Intelligence Index across reasoning, math and coding.
71.071.069.068.066.0
LiveBench
Contamination-resistant benchmark refreshed monthly — a strong signal of raw capability.
89.189.387.986.885.7
GPQA
Graduate-level science QA. Above 70% is frontier reasoning territory.
93.6%94.0%92.8%91.9%90.7%
MMLU-Pro
Broad knowledge across 57 subjects — the classic capability floor.
91.3%92.1%90.6%90.8%89.4%
SWE-Bench
Real-world GitHub bug-fixing. The single best proxy for agentic coding.
84.1%80.4%79.8%78.2%77.4%
Terminal-Bench
End-to-end shell tasks. Measures tool-use and long-horizon execution.
69.2%66.8%67.5%65.1%63.8%
ARC-AGI
Abstract reasoning puzzles. Historically brutal — even small gains matter.
45.8%49.5%43.7%42.8%39.1%
Aider Polyglot
Multi-language code editing benchmark. Signals practical dev-loop quality.
89.1%85.7%86.4%84.9%86.8%
Context
Maximum input tokens. Bigger unlocks whole-codebase and long-doc workflows.
1.0M1.0M500K1.0M1.0M
Speed (tok/s)
Output tokens per second. Matters for interactive UIs and long generations.
4872865043
Input $/1M
Cost per million input tokens.
$10.00$2.00$2.00$4.00$0.24
Output $/1M
Cost per million output tokens.
$50.00$10.00$6.00$20.00$11.94

Analysis // Model by model

Entry 01 · Anthropic

Anthropic: Claude Fable 5.1

Claude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work: long code refactors, front-end and visual...

Key Telemetry
Arena Elo
1644
GPQA
93.6%
SWE-Bench
84.1%
Context
1.0M
Entry 02 · Google

Google: Gemini 4 Argon

Gemini 4 Argon is Google's flagship reasoning model, built for complex software engineering, deep mathematical and scientific problem solving, and autonomous multi-step agents. Google trained it to keep context across...

Key Telemetry
Arena Elo
1638
GPQA
94.0%
SWE-Bench
80.4%
Context
1.0M
Entry 03 · xAI

SpaceXAI: Grok 4.7

Grok 4.7 is SpaceXAI's flagship model for coding, agentic tasks, and knowledge work, succeeding Grok 4.6. It is particularly strong at long-running software engineering tasks, verifying its own work, and...

Key Telemetry
Arena Elo
1634
GPQA
92.8%
SWE-Bench
79.8%
Context
500K
Entry 04 · Meta

Meta: Muse Wonder

Muse Wonder is a frontier reasoning model from Meta, designed for complex personal and professional agentic tasks. It accepts text, images, video, audio, and PDF documents and returns text, with...

Key Telemetry
Arena Elo
1629
GPQA
91.9%
SWE-Bench
78.2%
Context
1.0M
Entry 05 · Moonshot

MoonshotAI: Kimi K3

Kimi K3 is a 2.8T parameter open-weight multimodal reasoning model from Moonshot AI. It is suited for complex coding, knowledge work, and long-horizon agentic workflows, and is particularly strong at...

Key Telemetry
Arena Elo
1621
GPQA
90.7%
SWE-Bench
77.4%
Context
1.0M

Decision Protocol // Which to pick

01

Agentic coding

Optimize for SWE-Bench and Terminal-Bench. Aider Polyglot is the tiebreaker for real dev-loop quality.

02

Hard reasoning & research

GPQA and ARC-AGI matter more than MMLU. A high Arena Elo helps for open-ended prompts.

03

Long-context work

Filter by context window first (200K+ for full-repo work), then compare LiveBench to avoid quality drop-off.

04

Price-sensitive production

Input and output $/1M dominate at scale. Sort by price, then take the highest AA Index still in budget.