LLM Reference

Claude Mythos Preview vs Phi-4 Reasoning Vision 15B

Claude Mythos Preview (2026) and Phi-4 Reasoning Vision 15B (2026) are frontier reasoning models from Anthropic and Microsoft Research. Claude Mythos Preview ships a 1m-token context window, while Phi-4 Reasoning Vision 15B ships a not-yet-sourced context window. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads. It focuses on practical selection signals rather than broad model-family marketing.

Claude Mythos Preview is safer overall; choose Phi-4 Reasoning Vision 15B when vision-heavy evaluation matters.

Decision scorecard

Local evidence first
SignalClaude Mythos PreviewPhi-4 Reasoning Vision 15B
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsmultimodal apps
Decision fitCoding, RAG, and AgentsVision
Context window1m
Cheapest output$125/1M tokens-
Provider routes2 tracked0 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose Claude Mythos Preview when...
  • 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 Reasoning, Function calling, and Tool use in local model data.
  • Local decision data tags Claude Mythos Preview for Coding, RAG, and Agents.
Choose Phi-4 Reasoning Vision 15B when...
  • Local decision data tags Phi-4 Reasoning Vision 15B for Vision.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Claude Mythos Preview

$51,250

Cheapest tracked route/tier: Anthropic

Phi-4 Reasoning Vision 15B

Unavailable

No complete token price in local provider data

Cost delta unavailable until both models have sourced input and output token prices.

Switch friction

Claude Mythos Preview -> Phi-4 Reasoning Vision 15B
  • No overlapping tracked provider route is sourced for Claude Mythos Preview and Phi-4 Reasoning Vision 15B; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Reasoning, Function calling, and Tool use before moving production traffic.
Phi-4 Reasoning Vision 15B -> Claude Mythos Preview
  • No overlapping tracked provider route is sourced for Phi-4 Reasoning Vision 15B and Claude Mythos Preview; plan for SDK, billing, or endpoint changes.
  • Claude Mythos Preview adds Reasoning, Function calling, and Tool use in local capability data.

Specs

Specification
Released2026-05-012026-03-12
Context window1m
Parameters15B
ArchitectureDecoder Only-
LicenseProprietaryMITOSI-approved
OpennessProprietaryOpen source
Commercial useCommercial use: conditionalCommercial use: permitted
Knowledge cutoff2025-122025-03

Pricing and availability

Pricing attributeClaude Mythos PreviewPhi-4 Reasoning Vision 15B
Input price$25/1M tokens-
Output price$125/1M tokens-
Providers-

Capabilities

CapabilityClaude Mythos PreviewPhi-4 Reasoning Vision 15B
VisionYesYes
MultimodalYesYes
ReasoningYesNo
Function callingYesNo
Tool useYesNo
Structured outputsYesNo
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark scores are currently available for this pair.

Deep dive

The capability footprint differs most on reasoning mode: Claude Mythos Preview, function calling: Claude Mythos Preview, tool use: Claude Mythos Preview, structured outputs: Claude Mythos Preview, and code execution: Claude Mythos Preview. Both models share vision and multimodal input, 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 Phi-4 Reasoning Vision 15B 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 Phi-4 Reasoning Vision 15B 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. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.

FAQ

Is Claude Mythos Preview or Phi-4 Reasoning Vision 15B open source?

Claude Mythos Preview is listed under Proprietary. Phi-4 Reasoning Vision 15B is listed under MIT. 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 Phi-4 Reasoning Vision 15B?

Both Claude Mythos Preview and Phi-4 Reasoning Vision 15B expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.

Which is better for multimodal input, Claude Mythos Preview or Phi-4 Reasoning Vision 15B?

Both Claude Mythos Preview and Phi-4 Reasoning Vision 15B 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 Phi-4 Reasoning Vision 15B?

Claude Mythos Preview has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for function calling, Claude Mythos Preview or Phi-4 Reasoning Vision 15B?

Claude Mythos Preview has the clearer documented function calling signal in this comparison. If function calling is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run Claude Mythos Preview and Phi-4 Reasoning Vision 15B?

Claude Mythos Preview is available on Anthropic and Microsoft Foundry. Phi-4 Reasoning Vision 15B 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: 2026-06-15. Data sourced from public model cards and provider documentation.