Claude Mythos Preview vs Muse Spark
Claude Mythos Preview (2026) and Muse Spark (2026) are frontier-tier reasoning models from Anthropic and AI at Meta. Claude Mythos Preview ships a 1M-token context window, while Muse Spark ships a not-yet-sourced context window. On SWE-bench Verified, Claude Mythos Preview leads by 16.5 pts. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing.
Muse Spark is safer overall; choose Claude Mythos Preview when coding workflow support matters.
Decision scorecard
Local evidence first| Signal | Claude Mythos Preview | Muse Spark |
|---|---|---|
| Decision fit | Coding, RAG, and Agents | Coding, Agents, and Vision |
| Context window | 1M | — |
| Cheapest output | $125/1M tokens | - |
| Provider routes | 2 tracked | 0 tracked |
| Shared benchmarks | SWE-bench Verified leader | 2 rows |
Decision tradeoffs
- Claude Mythos Preview leads the largest shared benchmark signal on SWE-bench Verified by 16.5 points.
- Claude Mythos Preview has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Claude Mythos Preview has broader tracked provider coverage for fallback and procurement flexibility.
- Claude Mythos Preview uniquely exposes Structured outputs and Code execution in local model data.
- Local decision data tags Claude Mythos Preview for Coding, RAG, and Agents.
- Local decision data tags Muse Spark for Coding, Agents, and Vision.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output prices on this page.
Claude Mythos Preview
$51,250
Cheapest tracked route: Anthropic
Muse Spark
Unavailable
No complete token price in local provider data
Cost delta unavailable until both models have sourced input and output token prices.
Switch friction
- No overlapping tracked provider route is sourced for Claude Mythos Preview and Muse Spark; plan for SDK, billing, or endpoint changes.
- Check replacement coverage for Structured outputs and Code execution before moving production traffic.
- No overlapping tracked provider route is sourced for Muse Spark and Claude Mythos Preview; plan for SDK, billing, or endpoint changes.
- Claude Mythos Preview adds Structured outputs and Code execution in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-04-07 | 2026-04-08 |
| Context window | 1M | — |
| Parameters | — | — |
| Architecture | decoder only | decoder-only-transformer |
| License | Proprietary | Proprietary |
| Knowledge cutoff | 2025-12 | - |
Pricing and availability
| Pricing attribute | Claude Mythos Preview | Muse Spark |
|---|---|---|
| Input price | $25/1M tokens | - |
| Output price | $125/1M tokens | - |
| Providers | - |
Capabilities
| Capability | Claude Mythos Preview | Muse Spark |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | Yes |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | No |
| Code execution | Yes | No |
Benchmarks
| Benchmark | Claude Mythos Preview | Muse Spark |
|---|---|---|
| SWE-bench Verified | 93.9 | 77.4 |
| Google-Proof Q&A | 94.6 | 89.5 |
Deep dive
On shared benchmark coverage, SWE-bench Verified has Claude Mythos Preview at 93.9 and Muse Spark at 77.4, with Claude Mythos Preview ahead by 16.5 points; Google-Proof Q&A has Claude Mythos Preview at 94.6 and Muse Spark at 89.5, with Claude Mythos Preview ahead by 5.1 points. The largest visible gap is 16.5 points on SWE-bench Verified, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint differs most on structured outputs: Claude Mythos Preview and code execution: Claude Mythos Preview. Both models share vision, multimodal input, reasoning mode, and function calling, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
Pricing coverage is uneven: Claude Mythos Preview has $25/1M input tokens and Muse Spark has no token price sourced yet. Provider availability is 2 tracked routes versus 0. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.
Choose Claude Mythos Preview when coding workflow support and broader provider choice are central to the workload. Choose Muse Spark when vision-heavy evaluation are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Is Claude Mythos Preview or Muse Spark open source?
Claude Mythos Preview is listed under Proprietary. Muse Spark is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, Claude Mythos Preview or Muse Spark?
Both Claude Mythos Preview and Muse Spark expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for multimodal input, Claude Mythos Preview or Muse Spark?
Both Claude Mythos Preview and Muse Spark expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Which is better for reasoning mode, Claude Mythos Preview or Muse Spark?
Both Claude Mythos Preview and Muse Spark expose reasoning mode. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Which is better for function calling, Claude Mythos Preview or Muse Spark?
Both Claude Mythos Preview and Muse Spark expose function calling. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Where can I run Claude Mythos Preview and Muse Spark?
Claude Mythos Preview is available on Anthropic and Microsoft Foundry. Muse Spark is available on the tracked providers still being sourced. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-16. Data sourced from public model cards and provider documentation.