> ## Documentation Index
> Fetch the complete documentation index at: https://fastchat.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# FastChat

> FastChat is an open platform for training, serving, and evaluating large language model based chatbots

**The core features include:**

<Card title="The training and evaluation code" icon="code" iconType="duotone">
  Working with state-of-the-art models (e.g., Vicuna).
</Card>

<Card title="A distributed multi-model serving system" icon="gears" iconType="duotone">
  Includes web UI and OpenAI-compatible RESTful APIs.
</Card>

## News

* \[2023/08] 🔥 We released **Vicuna v1.5** based on Llama 2 with 4K and 16K context lengths. Download [weights](#vicuna-weights).

* \[2023/08] 🔥 We released **LongChat v1.5** based on Llama 2 with 32K context lengths. Download [weights](#longchat).

* \[2023/07] We released **Chatbot Arena Conversations**, a dataset containing 33k conversations with human preferences. Download it [here](https://huggingface.co/datasets/lmsys/chatbot_arena_conversations).

* \[2023/06] We introduced **MT-bench**, a challenging multi-turn question set for evaluating chatbots. Check out the blog [post](https://lmsys.org/blog/2023-06-22-leaderboard/).

* \[2023/06] We introduced **LongChat**, our long-context chatbots and evaluation tools. Check out the blog [post](https://lmsys.org/blog/2023-06-29-longchat/).

* \[2023/05] We introduced **Chatbot Arena** for battles among LLMs. Check out the blog [post](https://lmsys.org/blog/2023-05-03-arena).

* \[2023/03] We released **Vicuna: An Open-Source Chatbot Impressing GPT-4 with 90% ChatGPT Quality**. Check out the blog [post](https://vicuna.lmsys.org).

<Accordion title="More">
  - \[2023/06] We introduced **MT-bench**, a challenging multi-turn question set for evaluating chatbots. Check out the blog [post](https://lmsys.org/blog/2023-06-22-leaderboard/).
  - \[2023/06] We introduced **LongChat**, our long-context chatbots and evaluation tools. Check out the blog [post](https://lmsys.org/blog/2023-06-29-longchat/).
  - \[2023/05] We introduced **Chatbot Arena** for battles among LLMs. Check out the blog [post](https://lmsys.org/blog/2023-05-03-arena).
  - \[2023/03] We released **Vicuna: An Open-Source Chatbot Impressing GPT-4 with 90% ChatGPT Quality**. Check out the blog [post](https://vicuna.lmsys.org).
</Accordion>