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OpenCode Integrates Tencent Hy3 Preview for Low Cost Reasoning and Long Context

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OpenCode Integrates Tencent Hy3 Preview for Low Cost Reasoning and Long Context
OpenCode, an open-source AI coding agent, integrated the Hy3 preview model from Tencent. This text-only reasoning model features a 256K context window (the data a model processes at once) and uses a Mixture-of-Experts architecture (where only specific sub-networks activate per task) with 295B total and 21B active parameters.

This follows a trend of OpenCode adding models like Opus 4.7 for massive context and Xiaomi's MiMo-V2 for agentic optimization. By adding Hy3, OpenCode provides a reasoning-heavy alternative that prioritizes AI economics. The 21B active parameter count enables frontier-level logic without the high token costs of dense models.

Use Hy3 preview within OpenCode to handle complex debugging and codebase-wide refactoring. The 256K context window is sufficient for most repositories. Access is free for a two-week preview period, allowing you to test the model's reasoning capabilities in autonomous workflows before it moves to standard pricing.

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Frequently asked questions

What is the Tencent Hy3 preview model?
Tencent Hy3 preview is the latest and most capable model in the Hunyuan series, specifically designed for complex reasoning tasks. It is a text-only model that supports a 256K context window, allowing it to process large amounts of information like entire codebases. It is currently available as a preview through the OpenCode agent platform.
How can I access Tencent Hy3 for free?
Users can access the Tencent Hy3 preview model for free through the OpenCode platform for a two-week period starting from the announcement date. This promotional window allows developers to test the model's reasoning and long-context capabilities in their coding workflows without incurring API costs before the model eventually transitions to standard pricing.
What are the technical specs of the Tencent Hy3 model?
The Hy3 preview is a large-scale model with 295 billion total parameters. It utilizes a Mixture of Experts architecture where only 21 billion parameters are active during any single request. This design allows the model to maintain high performance and reasoning capabilities while significantly reducing the computational resources and token costs required for inference.
Does Tencent Hy3 support images or multimodal input?
No, the Tencent Hy3 preview is a text-only model. While it is the strongest entry in the Hunyuan series to date and features advanced reasoning capabilities with a 256K context window, it does not currently support multimodal inputs like images, audio, or video. It is optimized specifically for text-based tasks and agentic coding workflows.
Why is Tencent Hy3 considered cost-effective?
The Hy3 model achieves lower token costs through its Mixture of Experts architecture, which features 295 billion total parameters but only 21 billion active parameters. By only activating a fraction of the model for each task, it delivers strong performance and reasoning capabilities with much higher efficiency than traditional dense models of a similar size.