update readme

readme.md

@@ -1,3 +1,28 @@
 # Inviter
 
-Discord bot that allows users to set up personalized invite links for their servers and have rotating invite codes
+Discord bot that allows users to set up personalized invite links for their servers and have rotating invite codes.
+
+
+# Technical information
+
+## Get invite
+
+path: `/invite/{discordGuildId}`
+method: `GET`
+
+behavior: Requesting this endpoint without headers will return bodyless redirect (307) response that directs to the
+discord invite link if successful. Error screens will be shown if there's an error. You can use `Accept` header to get
+the invite link in different formats for automation purposes.
+
+### Accepted headers
+
+#### `Accept`
+
+- `application/json` - Returns status 200 along with json object with `url` key that contains full discord invite link.
+If response is not 200, json will contain `error` key with error message.
+- `text/plain` - Returns status 200 along with plain text containing full discord invite link. Error responses will not have body.
+
+
+# Self-hosting
+
+There's Dockerfile and docker-compose.yml in the repository, I'm sure you can figure it out.