Hy4 preview vs Mouse-1: Features, Pricing & Which Is Better (2026)
A side-by-side comparison of Hy4 preview and Mouse-1 — features, pricing, and ideal use cases — to help you decide which AI tool fits your workflow.
Hy4 preview
Tencent
Tencent's open-weight Hy4 preview, a 770B-parameter Mixture-of-Experts model with 49B active parameters and a 1M-token context window.
Key features
- 770B Mixture-of-Experts Architecture: Holds 770 billion total parameters while activating only 49 billion per token, so capacity scales without proportional inference cost.
- 1M-Token Context Window: Accepts inputs exceeding one million tokens, allowing whole codebases, long document sets or extended agent traces in a single prompt.
- Apache 2.0 Open Weights: Released under a permissive licence that allows commercial use, modification and redistribution with no separate agreement.
- Productivity Task Focus: Tuned for real-world coding, office work and scientific research rather than narrow benchmark optimisation.
- Multi-Product Availability: Accessible globally through Tencent's WorkBuddy, CodeBuddy, Yuanbao and ima applications in addition to the raw weights.
- API Access via TokenHub and OpenRouter: Can be called through Tencent Cloud TokenHub or OpenRouter for teams that prefer hosted inference over self-hosting.
Best for
- Whole-Repository Code Work: Load an entire codebase into the million-token context to reason about refactors and cross-file dependencies at once.
- Long-Horizon Agent Tasks: Drive multi-step agent workflows where the full history of tool calls and intermediate results must stay in context.
- Self-Hosted Deployment: Run a frontier-scale open-weight model on private infrastructure where data cannot leave the organisation.
- Scientific Literature Analysis: Ingest large collections of papers or experimental logs and synthesise findings without chunking the input.
- Office Document Processing: Summarise, draft and restructure long reports, contracts and spreadsheets in enterprise workflows.
- Commercial Fine-Tuning: Adapt the weights for a proprietary product under the Apache 2.0 licence without negotiating a model licence.
Mouse-1
Mouse
Mouse-1 is a fast, low-cost decision model that plugs into agent harnesses to handle routing, gating and verification.
Key features
- Decision Layer for Agents: Takes agent state and options and returns probabilities so the harness can route, gate and verify.
- About 100 ms Latency: Answers faster than a chat model's first token.
- Batch Decisions: One request answers up to 128 questions.
- Prompt-Injection Resistance: Chooses only from supplied options; planted instructions changed 0% of decisions in vendor tests.
- Zero Data Retention: Requests are scored and dropped, never stored or used for training.
- Image and Document Classification: Handles content moderation, document routing and browser-state detection.
Best for
- Agent Routing: Deciding which model or tool an agent should use next.
- Action Gating: Approving or blocking risky agent actions cheaply.
- Content Moderation: Classifying images or text as safe or unsafe.
- Document Routing: Sending invoices, contracts and IDs to the right workflow.
- Browser Agents: Detecting screen state such as login required or error.
- Cost Reduction: Offloading small decisions from expensive frontier models.
