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Nous: DeepHermes 3 Mistral 24B Preview

nousresearch/deephermes-3-mistral-24b-preview

Created May 9, 202532,768 context
$0.02/M input tokens$0.10/M output tokens

DeepHermes 3 (Mistral 24B Preview) is an instruction-tuned language model by Nous Research based on Mistral-Small-24B, designed for chat, function calling, and advanced multi-turn reasoning. It introduces a dual-mode system that toggles between intuitive chat responses and structured “deep reasoning” mode using special system prompts. Fine-tuned via distillation from R1, it supports structured output (JSON mode) and function call syntax for agent-based applications.

DeepHermes 3 supports a reasoning toggle via system prompt, allowing users to switch between fast, intuitive responses and deliberate, multi-step reasoning. When activated with the following specific system instruction, the model enters a "deep thinking" mode—generating extended chains of thought wrapped in <think></think> tags before delivering a final answer.

System Prompt: You are a deep thinking AI, you may use extremely long chains of thought to deeply consider the problem and deliberate with yourself via systematic reasoning processes to help come to a correct solution prior to answering. You should enclose your thoughts and internal monologue inside <think> </think> tags, and then provide your solution or response to the problem.

Sample code and API for DeepHermes 3 Mistral 24B Preview

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