DeepSeek: DeepSeek V3.1 Terminus
Provided by OpenRouter
DeepSeek-V3.1 Terminus is an update to [DeepSeek V3.1](/deepseek/deepseek-chat-v3.1) that maintains the model's original capabilities while addressing issues reported by users, including language consistency and agent capabilities, further optimizing the model's performance in coding and search agents. It is a large hybrid reasoning model (671B parameters, 37B active) that supports both thinking and non-thinking modes. It extends the DeepSeek-V3 base with a two-phase long-context training process, reaching up to 128K tokens, and uses FP8 microscaling for efficient inference. Users can control the reasoning behaviour with the `reasoning` `enabled` boolean. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#enable-reasoning-with-default-config) The model improves tool use, code generation, and reasoning efficiency, achieving performance comparable to DeepSeek-R1 on difficult benchmarks while responding more quickly. It supports structured tool calling, code agents, and search agents, making it suitable for research, coding, and agentic workflows.
Specifications
163,840 tokens$0.210/M$0.790/MAbout DeepSeek: DeepSeek V3.1 Terminus
DeepSeek-V3.1 Terminus is an update to [DeepSeek V3.1](/deepseek/deepseek-chat-v3.1) that maintains the model's original capabilities while addressing issues reported by users, including language consistency and agent capabilities, further optimizing the model's performance in coding and search agents. It is a large hybrid reasoning model (671B parameters, 37B active) that supports both thinking and non-thinking modes. It extends the DeepSeek-V3 base with a two-phase long-context training process, reaching up to 128K tokens, and uses FP8 microscaling for efficient inference. Users can control the reasoning behaviour with the `reasoning` `enabled` boolean. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#enable-reasoning-with-default-config) The model improves tool use, code generation, and reasoning efficiency, achieving performance comparable to DeepSeek-R1 on difficult benchmarks while responding more quickly. It supports structured tool calling, code agents, and search agents, making it suitable for research, coding, and agentic workflows.
Strengths
- •Large context window (164k tokens) for long conversations
Use Cases
- •Content creation and writing assistance
- •General conversations and Q&A
Limitations
Performance may vary based on query complexity, context length, and task type. Consider using higher-tier models for production-critical applications.
Sample Prompts
Try these prompts to explore DeepSeek: DeepSeek V3.1 Terminus's capabilities:
Explain quantum computing in simple terms like I'm 10 years old
Write a compelling email asking for a meeting to discuss a project proposal
Help me brainstorm creative solutions for improving team productivity
Tip: Customize these prompts to fit your specific needs and use cases.
Premium Model
This model requires credits to use. DeepSeek: DeepSeek V3.1 Terminus offers advanced capabilities and high-performance features for production-grade applications.
Credits required for premium models. Free models are available without credits.
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