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+### What is it
+Userinfo is a size-limited buffer for storing and exchanging information about client settings in `\key\value` format.
+
+### Registered prefixes
+`*` - Protected engine keys that can not be changed by console.
+<br>`_` - Private keys that will not be transmitted to other clients.
+
+| Key | Value type | Important | Usage on server | Usage on other clients | Comment |
+|------ |-----|-----|-----|--------|------|
+| name | string | :heavy_check_mark: | Holding player's name. | Holding player's name. |
+| model | string | :heavy_check_mark: | Holding player's model. | Holding player's model. | Can be blocked and replaced by using modelindex (See [#342](https://github.com/dreamstalker/rehlds/issues/342)) |
+| topcolor | integer | :heavy_check_mark: | :x: | Top color of player's model. Used in Half-Life. | Does not supported in Counter-Strike and many other mods. In this case you can block transmitting of this key.
+| bottomcolor | integer | :heavy_check_mark: | :x: | Bottom color of player's model. Used in Half-Life. | Does not supported in Counter-Strike and many other mods. In this case you can block transmitting of this key. |
+| rate | integer | :heavy_check_mark: | Maximum packets rate from the server to client in bytes/sec.  | :x: |
+| cl_updaterate | integer | :heavy_check_mark: | Maximum game world update packets rate from the server to client in packets/sec. | :x: |
+| cl_lw | integer | :heavy_check_mark: | Enable client-side weapon firing prediction. | :x: |
+| cl_lc | integer | :heavy_check_mark: | Enable/disable lag compensation. | :x: |
+| *hltv | integer | :heavy_check_mark: | Flag of HLTV proxies. | :x: |
+| *sid | int64 | :heavy_check_mark: | :x: | Showing steam avatars in the scores tab. | Don't try to hide steamid's by blocking this key. There are many other open places to get it: steam profile info, various webstats, forums, etc... |
+| _cl_autowepswitch | integer | :x: | :x: | :x: | Switch automatically to picked up weapons. There is no need to transfer this key. |
+| _vgui_menus | integer | :heavy_check_mark: | Enable/disable new style (gui) menus. | :x: |
+| _ah | integer | :x: | Enable/disable showing help messages. | :x: |
+| cl_dlmax | integer | :x: | Wanted fragment size when downloading files directly from the server.  | :x: |
+| hslots | integer | :x: |  HLTV number of slots. | :x: |
+| hdelay | integer | :x: | HLTV broadcasting delay. | :x: |
+| hspecs | integer | :x: | HLTV number of spectators. | :x: |
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