Muse Spark 1.2vsKimi K2.5
Muse Spark 1.2 | Kimi K2.5 | |
|---|---|---|
| Specifications | ||
Parameters | — | 1T |
Context window | 1M | 256k |
| Benchmarks | ||
Nonsense detection BullshitBench v2Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. | — | 52% |
Coding SWE-Bench VerifiedReal coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better. | — | 76.8% |
Agentic coding CursorBench v3.1Cursor's own test of harder, real-world coding tasks inside a code editor. Higher is better. | — | 31.9% |
Agentic coding DeepSWE 1.1Artificial Analysis' independent test of deep, agentic software-engineering work — the AI has to plan and carry out substantial coding tasks end to end. (Version 1.1 of the test.) Higher is better. | 59.3% | — |
Next.js coding Next.js EvalsVercel's open eval of how well AI coding agents build and migrate real Next.js apps — measured as the share of tasks the agent completes successfully. Higher is better. | — | 21% |
Competitive coding LiveCodeBenchCoding problems published so recently the AI can't have seen them in training — a contamination-free test of raw programming skill. Higher is better. | — | 85% |
Agentic terminal coding Terminal-Bench 2.1Can the AI work in a command-line terminal — running commands and finishing technical setup tasks the way a developer would? Higher is better. | 82.9% | — |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | — | 87.6% |
Community preference (code) Arena Elo (Code)Like the text arena, but people vote on which AI writes better code. The votes become a chess-style Elo rating on arena.ai. Higher is better. | — | 1433 |
| Overview | ||
| Company | Meta | Moonshot AI |
| Release date | Aug 5 2026 | Jan 27 2026 |
| Access | Proprietary | Open Weight |
Which is better: Muse Spark 1.2 or Kimi K2.5?
Muse Spark 1.2 and Kimi K2.5 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Kimi K2.5 shipped 190 days before Muse Spark 1.2, so benchmark comparisons should account for the intervening progress.
Context windows are 1M (Muse Spark 1.2) vs 256k (Kimi K2.5). Muse Spark 1.2 is proprietary, while Kimi K2.5 is open weight.
Direct benchmark comparisons are unavailable — Muse Spark 1.2 and Kimi K2.5 don't publish scores on any of the same benchmarks.
Frequently asked questions
Muse Spark 1.2 was released by Meta on Aug 5 2026.
Kimi K2.5 was released by Moonshot AI on Jan 27 2026.
Muse Spark 1.2 has a 1M context window; Kimi K2.5 has 256k.
Muse Spark 1.2 is a proprietary model released by Meta. Kimi K2.5 is an open weight model released by Moonshot AI.