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readme.MD

@@ -60,20 +60,31 @@ which is necessary for continuous integration (CI).
 - _Worker_ [limits](https://developers.cloudflare.com/workers/platform/limits/#worker-limits)
 
 ## How to use
+If you open your newly-deployed site in a browser, you will only see a `404 Not Found` message. This is expected, as the API is not designed for direct browser access.
+To utilize it, you should enter your API address and your Gemini API key into the corresponding fields in your software settings.
 
 > [!NOTE]
-> Not all tools allows overriding the OpenAI endpoint, but many do
+> Not all software tools allow overriding the OpenAI endpoint, but many do
 > (however these settings can sometimes be deeply hidden).
 
-Use the endpoint address wherever you can specify it.
+Typically, you should specify the API base in this format:  
+`https://my-super-proxy.vercel.app/v1`
+
+However, some software may expect it without the `/v1` ending:  
+`https://my-super-proxy.vercel.app`
+
 The relevant field may be labeled as "_OpenAI proxy_".
 You might need to look under "_Advanced settings_" or similar sections.
-Or in some config file.
-
-For some command-line tools, you may need to set an environment variable, _e.g._:  
-`set OPENAI_BASE_URL=https://my-super-proxy.vercel.app/v1`  
-_..or_:  
-`set OPENAI_API_BASE=https://my-super-proxy.vercel.app/v1`
+Alternatively, it could be in some config file (check the relevant documentation for details).
+
+For some command-line tools, you may need to set an environment variable, _e.g._:
+```sh
+set OPENAI_BASE_URL=https://my-super-proxy.vercel.app/v1
+```
+_..or_:
+```sh
+set OPENAI_API_BASE=https://my-super-proxy.vercel.app/v1
+```
 
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