allow change model name

usage.md

@@ -35,6 +35,8 @@ module.exports = {
 
     （可选）如果需要，可以设置代理。
 
+    （可选）如果需要，可以修改使用的模型。但是仍然建议使用opus，因为其他未经测试。
+
 8. 启动 start.bat
 
 9. 酒馆中选择 Claude，反向代理地址填 http://127.0.0.1:8080/v1 **反代密码必须填, 同时打开流式传输**，随便什么都可以（除非你在第7步设置了PASSWORD）。
@@ -49,6 +51,27 @@ module.exports = {
 
 欲知详细代理格式，请查阅 https://www.npmjs.com/package/proxy-from-env
 
+# 修改模型
+
+修改`AI_MODEL`环境变量可以切换模型，支持的模型名字如下 (请参考官网获取最新模型):
+
+```
+gpt_4o
+gpt_4_turbo
+gpt_4
+claude_3_opus
+claude_3_sonnet
+claude_3_haiku
+claude_2
+llama3
+gemini_pro
+gemini_1_5_pro
+databricks_dbrx_instruct
+command_r
+command_r_plus
+zephyr
+```
+
 ## 注意事项
 
 出现 403 错误请重新抓 COOKIE 或者更换代理出口 IP。
@@ -91,6 +114,8 @@ module.exports = {
    
    (Optional) You can set the proxy in start.bat. See below.
 
+   (Optional) You may change the model to use, but only claude_3_opus is tested.
+
 8. Start start.bat
 
 9. Select Claude in the Tavern and put http://127.0.0.1:8080/v1 as the address of the reverse proxy. **Use any random string for password, also turn on Streaming** (unless you set PASSWORD in step 7).
@@ -101,6 +126,29 @@ module.exports = {
 
 Use the `https_proxy` env to set custom proxy. Refer to https://www.npmjs.com/package/proxy-from-env for detail.
 
+# Change model
+
+Change `AI_MODEL` env to switch between models.
+
+Supported model names (refer to you.com website for latest models):
+
+```
+gpt_4o
+gpt_4_turbo
+gpt_4
+claude_3_opus
+claude_3_sonnet
+claude_3_haiku
+claude_2
+llama3
+gemini_pro
+gemini_1_5_pro
+databricks_dbrx_instruct
+command_r
+command_r_plus
+zephyr
+```
+
 ## Caution
 
 If you get 403 errors, consider getting the cookie again or changing your IP.