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Pyyan / Compare / Muse Spark 1.3 vs Claude Fable 5

Muse Spark 1.3 vs Claude Fable 5

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Language Models · verified 5 Sept 2026

Muse Spark 1.3Metacurrent
Claude Fable 5Anthropiccurrent
3 slots left
SpecificationMuse Spark 1.3Claude Fable 5
SummaryA quarter fewer tokens than 1.2 for the same work, which is the figure on the bill.Most capable widely released model, for the hardest reasoning and long-horizon agentic work.
Context1M1M
Input ($/Mtok)$1.25$10
Output ($/Mtok)$4.25$50
LicenceProprietaryProprietary
Max outputNot published128K
ParametersNot published—
Released2 Sep 2026—
Model IDmuse-spark-1.3claude-fable-5
CategoryLanguage ModelsLanguage Models
Official—Anthropic ↗

Highlighted rows are where these differ.

Muse Spark 1.3

  • About 20% fewer tool calls and 25% fewer tokens than 1.2 to reach the same result
  • 75.4 on DeepSWE v1.1 and 98.5 on MRCR long context between 256K and 512K
  • A Contributor tier costs $0.10 in and $0.20 out for the same model, in exchange for letting Meta train on your prompts

Best for long running agentic coding.

Full spec sheet →

Claude Fable 5

  • Thinking is always on — the `thinking` param is rejected
  • Raw chain of thought is never returned
  • Requires 30-day data retention; unavailable under ZDR

Best for the hardest problems.

Full spec sheet →