Claude Fable 5.2 vs Muse Spark Open
Claude Fable 5.2 leads Muse Spark Open on coding, 87.8 to 43.4 on the Vibe Coding Index, and Muse Spark Open costs 9.4x less per output token ($4.25 vs $40.00 per million). Updated November 14, 2026; 40 benchmarks have a result for both.
Claude Fable 5.2 or Muse Spark Open: which to pick
Pick Claude Fable 5.2 for coding: it scores 87.8 on the Vibe Coding Index against 43.4 for Muse Spark Open.
Pick Muse Spark Open for output tokens 9.4x cheaper ($4.25 vs $40.00 per million) and a larger context window (1.05M against 1M tokens).
- Shared results
- 40
- Claude Fable 5.2 only
- 28
- Muse Spark Open only
- 7
- Like-for-like categories
- 8 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, six public coding benchmarks
Claude Fable 5.2
Claude Fable 5.2 scores 87.8 against 43.4.
4 benchmarks behind each score
Intelligence
AA Intelligence Index
Claude Fable 5.2
Claude Fable 5.2 leads, 64.6 against 24.9.
Same board, both measured
Web design
Design Arena: websites
Claude Fable 5.2
Claude Fable 5.2 leads, 1351 against 1306.
Same board, both measured
General
Vals Index
Claude Fable 5.2
Claude Fable 5.2 leads, 71.3% against 48.6%.
Same board, both measured
Long documents
Listed context window
Muse Spark Open
Muse Spark Open takes 1.05M tokens against 1M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Muse Spark Open
Claude Fable 5.2 $0.028, Muse Spark Open $0.0034 per turn.
List prices
At a glance
- Coding index
- Claude Fable 5.2 87.8 from 4 benchmarks, Muse Spark Open 43.4 from 4 benchmarks.
- Widest category
- Math, 57.2 points apart on average over 1 shared benchmark.
- Widest single gap
- Terminal-Bench 4 (Vals AI): Claude Fable 5.2 65.2% against Muse Spark Open 6.6%, 78.1 points apart on a 0 to 100 scale.
- Output price
- Claude Fable 5.2 $40.00 against Muse Spark Open $4.25 per million output tokens, 9.4x apart.
- Context window
- Claude Fable 5.2 takes 1M tokens, Muse Spark Open 1.05M.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | Claude Fable 5.2 | Bars | Muse Spark Open | Ties |
|---|---|---|---|---|
| Coding | 11 | 0 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 6 | 1 | ||
| Reasoning | 7 | 0 | ||
| Math | 1 | 0 | ||
| Knowledge | 1 | 1 | ||
| Web design | 6 | 0 | ||
| General | 4 | 0 | ||
| All shared boards | 38 | 2 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index110
| Benchmark | Claude Fable 5.2 | Muse Spark Open | Leader |
|---|---|---|---|
| LiveBench coding | 79.2% | 55.1% | Claude Fable 5.2 |
| LMArena WebDev | 1838 | 1526 | Claude Fable 5.2 |
| Terminal-Bench 4 (Vals AI) | 65.2% | 6.6% | Claude Fable 5.2 |
| Vibe Code Bench (Vals AI) | 93.8% | 76.2% | Claude Fable 5.2 |
| Code migration (Vals AI) | Not measured | 21.2% | Only Muse Spark Open measured |
| ProgramBench (Vals AI) | 19.0% | Not measured | Only Claude Fable 5.2 measured |
| SWE-bench Multimodal (Vals AI) | 62.3% | Not measured | Only Claude Fable 5.2 measured |
| SciCode | 67.7% | 58.4% | Claude Fable 5.2 |
| Terminal-Bench 4.0 (Artificial Analysis run) | 61.6% | 8.1% | Claude Fable 5.2 |
| FrontierCode 2.0 | 49.1% | 7.6% | Claude Fable 5.2 |
| FrontierSWE | 69.9% | Not measured | Only Claude Fable 5.2 measured |
| ALE-Bench | 2509.8 | 1590.1 | Claude Fable 5.2 |
| LMArena WebDev: React | 1915 | 1523 | Claude Fable 5.2 |
| LMArena WebDev: HTML | 1738 | 1475 | Claude Fable 5.2 |
| SWE-Bench Pro V2 | Not measured | 95.0% | Only Muse Spark Open measured |
| GameBench 2 | 99.1 | 59.3 | Claude Fable 5.2 |
| CursorBench 4.0 | 60.0% | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 35 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Fable 5.2 | Muse Spark Open | Leader |
|---|---|---|---|
| AA Intelligence Index | 64.6 | 24.9 | Claude Fable 5.2 |
| Epoch Capabilities Index | 173.4 | 155.4 | Claude Fable 5.2 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index61
| Benchmark | Claude Fable 5.2 | Muse Spark Open | Leader |
|---|---|---|---|
| Design Arena: agents building full-stack apps | 1402 | Not measured | Only Claude Fable 5.2 measured |
| Design Arena: agents building mobile apps | 1325 | Not measured | Only Claude Fable 5.2 measured |
| Design Arena: spreadsheets | 1434 | Not measured | Only Claude Fable 5.2 measured |
| LiveBench research | 94.5% | 82.7% | Claude Fable 5.2 |
| LiveBench browser | 86.9% | 26.2% | Claude Fable 5.2 |
| LiveBench long agentic | 82.9% | 12.1% | Claude Fable 5.2 |
| Finance Agent (Vals AI) | Not measured | 61.3% | Only Muse Spark Open measured |
| Tax Agent Bench (Vals AI) | 32.1% | 26.3% | Claude Fable 5.2 |
| Legal Research Bench (Vals AI) | 46.1% | 38.5% | Claude Fable 5.2 |
| Harvey's Legal Agent Benchmark (Vals AI) | 5.0% | 25.0% | Muse Spark Open |
| Excel Modeling Benchmark (Vals AI) | Not measured | 53.7% | Only Muse Spark Open measured |
| BioMysteryBench (Vals AI) | 83.7% | Not measured | Only Claude Fable 5.2 measured |
| Terminal-Bench-Science (Vals AI) | 55.7% | Not measured | Only Claude Fable 5.2 measured |
| Vals Science Index | 63.7% | Not measured | Only Claude Fable 5.2 measured |
| APEX-Agents | 80.1% | 33.4% | Claude Fable 5.2 |
| Remote Labor Index | 41.3% | Not measured | Only Claude Fable 5.2 measured |
| SpireClimb | 15.5% | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 27 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index70
| Benchmark | Claude Fable 5.2 | Muse Spark Open | Leader |
|---|---|---|---|
| LiveBench reasoning | 88.8% | 73.7% | Claude Fable 5.2 |
| MysteryMechanism (Vals AI) | 51.8% | Not measured | Only Claude Fable 5.2 measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 89.0% | Only Muse Spark Open measured |
| Humanity's Last Exam (Artificial Analysis run) | 74.3% | 43.9% | Claude Fable 5.2 |
| HLE-Diamond (Artificial Analysis run) | 80.2% | 26.3% | Claude Fable 5.2 |
| CritPt v2, hard subset (Artificial Analysis run) | 76.5% | 29.5% | Claude Fable 5.2 |
| GPQA Diamond (Epoch AI run) | 93.9% | Not measured | Only Claude Fable 5.2 measured |
| ARC-AGI | 98.5% | 89.0% | Claude Fable 5.2 |
| ARC-AGI-2 | 93.8% | 57.5% | Claude Fable 5.2 |
| SimpleBench | 94.9% | Not measured | Only Claude Fable 5.2 measured |
| Chess puzzles | 79.0% | Not measured | Only Claude Fable 5.2 measured |
| Mystery game puzzles | 90.0% | Not measured | Only Claude Fable 5.2 measured |
| EBR-bench | 90.5% | Not measured | Only Claude Fable 5.2 measured |
| Humanity's Last Exam (Scale run) | 72.4% | 28.0% | Claude Fable 5.2 |
| GoBench | 2566 | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 11 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Fable 5.2 | Muse Spark Open | Leader |
|---|---|---|---|
| OTIS Mock AIME | 99.7% | Not measured | Only Claude Fable 5.2 measured |
| FrontierMath, tiers 1 to 3 | 95.1% | Not measured | Only Claude Fable 5.2 measured |
| FrontierMath, tier 4 | 100.0% | Not measured | Only Claude Fable 5.2 measured |
| ProofBench | 100.0% | Not measured | Only Claude Fable 5.2 measured |
| MathArena | 82.8% | 25.6% | Claude Fable 5.2 |
| Neither model has a result on the other 9 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index11
| Benchmark | Claude Fable 5.2 | Muse Spark Open | Leader |
|---|---|---|---|
| AA-Omniscience | 66.8 | 25.8 | Claude Fable 5.2 |
| SimpleQA Verified | 94.0% | Not measured | Only Claude Fable 5.2 measured |
| PRBench Finance | 47.1% | Not measured | Only Claude Fable 5.2 measured |
| PRBench Legal | 49.0% | 59.8% | Muse Spark Open |
| Neither model has a result on the other 17 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Fable 5.2 | Muse Spark Open | Leader |
|---|---|---|---|
| Design Arena: websites | 1351 | 1306 | Claude Fable 5.2 |
| Design Arena: UI components | 1371 | 1312 | Claude Fable 5.2 |
| Design Arena: game dev | 1396 | 1265 | Claude Fable 5.2 |
| Design Arena: 3D | 1517 | 1247 | Claude Fable 5.2 |
| Design Arena: all code categories | 1373 | 1301 | Claude Fable 5.2 |
| LiveBench design | 85.1% | 58.1% | Claude Fable 5.2 |
| Neither model has a result on the other 3 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Fable 5.2 | Muse Spark Open | Leader |
|---|---|---|---|
| Vals Index | 71.3% | 48.6% | Claude Fable 5.2 |
| LiveBench data analysis | 81.5% | 60.2% | Claude Fable 5.2 |
| SAGE (Vals AI) | Not measured | 85.8% | Only Muse Spark Open measured |
| Long context reasoning (AA-LCR) | 83.3% | 78.3% | Claude Fable 5.2 |
| GDPval-AA | 1831 | 1401 | Claude Fable 5.2 |
| DTBench | 99.2% | Not measured | Only Claude Fable 5.2 measured |
| LMCA | 70.6% | Not measured | Only Claude Fable 5.2 measured |
| Furniture assembly | 90.0% | Not measured | Only Claude Fable 5.2 measured |
| MultiChallenge | Not measured | 74.2% | Only Muse Spark Open measured |
| Neither model has a result on the other 40 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Fable 5.2 | Muse Spark Open | Leader |
|---|---|---|---|
| Neither model has a result on 5 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
Muse Spark Open costs less
Repository review
50K input + 3K output tokens
Muse Spark Open costs less
Agent loop
200K input + 10K output tokens
Muse Spark Open costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | Anthropic Claude Fable 5.2 | Meta Muse Spark Open |
|---|---|---|
| Maker | Anthropic | Meta |
| Weights | No public weights listed | Open weights |
| Released | November 9, 2026 | October 15, 2026 |
| Context window | 1M | 1.05M |
| Input $/Mtok | $8.00 | $1.25 |
| Output $/Mtok | $40.00 | $4.25 |
| Coding index | 87.8 | 43.4 |
| Independent measurements behind it | 4 | 4 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Fable 5.2 better than Muse Spark Open for coding?
Pick Claude Fable 5.2 for coding: it scores 87.8 on the Vibe Coding Index against 43.4 for Muse Spark Open. Pick Muse Spark Open for output tokens 9.4x cheaper ($4.25 vs $40.00 per million) and a larger context window (1.05M against 1M tokens).
Which is cheaper, Claude Fable 5.2 or Muse Spark Open?
Claude Fable 5.2 costs $8.00 per million input tokens and $40.00 per million output tokens; Muse Spark Open costs $1.25 and $4.25. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Fable 5.2 or Muse Spark Open?
Muse Spark Open, with 1.05M tokens against 1M.
How many benchmarks is the Claude Fable 5.2 vs Muse Spark Open comparison based on?
40 benchmarks have a result for both models as of November 14, 2026. Claude Fable 5.2's coding index rests on 4 independent benchmarks and Muse Spark Open's on 4. Where only one model has a result, the page says so instead of naming a winner.