Claude Opus 5.5 vs Muse Spark 1.3
Claude Opus 5.5 scores higher on the Models at Work leaderboard (91 vs 72 out of 100). Muse Spark 1.3 is about 10× cheaper per blended million tokens ($0.78 vs $8, one figure an Artificial Analysis estimate). On Artificial Analysis' independent Intelligence Index, Claude Opus 5.5 leads 58 to 48.
| Claude Opus 5.5 · Anthropic | Muse Spark 1.3 · Meta | |
|---|---|---|
| Leaderboard rank | #1 | #8 |
| Score (0–100) | 91 | 72 |
| Tier | Frontier | Workhorse |
| Price per 1M tokens | $4 in · $20 out | $0.78 blended (estimate) |
| Context window | 1M | Not verified |
| Open weights | No | Not verified |
| Artificial Analysis Intelligence Index | 58 | 48 |
| Arena text score | 1507 | 1494 |
| Humanity's Last Exam, Diamond (Scale) | 55.0 | — |
| Epoch Capabilities Index | 167 | — |
| DistressBench (Scale) | — | 84.88 |
| Best for | Agentic coding, Long-running agents, Enterprise knowledge work | Latency-first products, Customer-facing chat, Meta-ecosystem teams |
Choose Claude Opus 5.5 if…
- you need agentic coding
- you need long-running agents
- you need enterprise knowledge work
The model people actually ship agents on: top of the independent index, a price that does not need a budget meeting, and a community that complains mainly about how much it has to be used.
Caveats: Arena puts Gemini 4 Argon ahead on chat preference; the gap is inside two scores' error bars.
Choose Muse Spark 1.3 if…
- you need latency-first products
- you need customer-facing chat
- you need meta-ecosystem teams
The fastest thing in the table by a distance, and the one to beat on the stress benchmark nobody else talks about.
What practitioners say
Claude Opus 5.5: The launch thread was the biggest Claude thread of the year on Hacker News, a port of the TypeScript compiler to Rust credited the model with a working build in ten hours, and a Vals AI materials-discovery run used it for agentic simulation. A 'has it been nerfed yet' tracker is the most-upvoted scepticism.
Questions people ask
Which is better, Claude Opus 5.5 or Muse Spark 1.3?
Claude Opus 5.5 scores higher on the Models at Work leaderboard (91 vs 72 out of 100). Muse Spark 1.3 is about 10× cheaper per blended million tokens ($0.78 vs $8, one figure an Artificial Analysis estimate). On Artificial Analysis' independent Intelligence Index, Claude Opus 5.5 leads 58 to 48.
When should I choose Claude Opus 5.5 over Muse Spark 1.3?
Choose Claude Opus 5.5 for agentic coding, long-running agents, enterprise knowledge work. The model people actually ship agents on: top of the independent index, a price that does not need a budget meeting, and a community that complains mainly about how much it has to be used.
When should I choose Muse Spark 1.3 over Claude Opus 5.5?
Choose Muse Spark 1.3 for latency-first products, customer-facing chat, meta-ecosystem teams. The fastest thing in the table by a distance, and the one to beat on the stress benchmark nobody else talks about.
Which is cheaper, Claude Opus 5.5 or Muse Spark 1.3?
Claude Opus 5.5 costs $4 per million input tokens and $20 per million output tokens on Anthropic's list price (Claude pricing, read Oct 10, 2026). Meta does not publish a simple list price for Muse Spark 1.3; Artificial Analysis estimates a blended $0.78 per million tokens (three input to one output).
Scores come from the Models at Work leaderboard: Score is 0 to 100: 50% independent evals normalised within this table, 20% price-performance, 15% practitioner sentiment from Signals and community threads, 15% operational fit (context, speed, availability, open weights). Models within three points are a tie in practice. Vendor-published figures are labelled as such and never counted as independent. Prices are vendor list prices where published; blended figures assume three input tokens per output token.