> For the complete documentation index, see [llms.txt](https://doc.sysdevmobile.com/mss-extensibility/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.sysdevmobile.com/mss-extensibility/mss-5.1/functions-mss-to-kalipso/clients/100-clients-clients-module.md).

# 100 - Clients Module

100 - Clients Module

| Event   | Extension action set  | Description                                                                                                    |
| ------- | --------------------- | -------------------------------------------------------------------------------------------------------------- |
| Before  | EXT\_0100\_1\_Before  | Will be executed before MSS open the customers module;                                                         |
| Replace | EXT\_0100\_2\_Replace | Will replace MSS customers module (can be used to validate if normal MSS module opens using outOpenMSSModule); |
| After   | EXT\_0100\_3\_After   | Will be executed after closing the customers module;                                                           |

Output Parameters:

* outOpenMSSModule – Return code: 1 – Open MSS module / 0 – Don’t open MSS module;