Extend readme

packages/scripts/README.md

@@ -5,16 +5,20 @@
 To send emails using the script, run the following command:
 
 ```sh
-
 pnpm stress:email email=some@**gmail**.com amount=100 [interval=60] [mode=individual|reply-chain]
-
 ```
 
 - `email`: The recipient's email address.
 - `amount`: Number of emails to send.
 - `interval` (optional): Time in seconds between emails. Default is 60.
 - `mode` (optional): `individual` or `reply-chain`. Default is `individual`.
 
+**Note:** This script assumes a `.env.test.local` file exists with the following values as specified in `env.ts`:
+
+```
+MAILBRIDGE_TRANSACTIONAL_CREDENTIALS={"apiUrl":"https://example.com","apiKey":"your-api-key","sendAsName":"Sender Name","sendAsEmail":"sender@example.com"}
+```
+
 ---
 
 ## Example