When the agent is logged in from a Freshdesk account, you might want to fetch some information like their agent ID, the source page from where the bot was initiated, ticket ID, etc, and display it in the bot conversation. The parameters for such information may not be readily available as a placeholder. The Custom Params feature helps to fetch this information.
Configuration :
1. Log into your Freshdesk account and navigate to Freddy Assist. In the bot builder, click on the Bot list icon from the left pane which displays the list of all the bots in the account. Then choose the Bot in which you would like to add the custom parameters. 
2. Make sure to choose the correct Bot Version from the drop-down at the top right corner. 
3. Now select the ‘Custom Parameters’ option available on the right pane. 
4. Then from that page, we would have the option ‘New Parameter’. 
5. From the window that slides from the right, proceed to enter the details necessary details and click on Save. 
How to use Custom Params?
1. Navigate to the dialog where you would like to use this value, click on the content picker and choose Custom Params.
2. Pick the param that you are looking for from the list (only API source custom params will be displayed here).
The Source field corresponds to the location from where the value of the param is pulled which could either be JS or API.
A. When JS is chosen and saved, the script that is generated upon clicking 'Generate Script' button contains this param as a key whose value can either be hardcoded or a variable from the website JS can be assigned to it.
B. Picking API in source opens a dynamic field API Response where you could use the content picker to select the API from the list and use one of its response headers to initialize the param. Once this API is called in a flow the param assumes the value of the response headers that are mapped with it.
Note:
* Make sure that the API related to a custom param is called before using it in a dialog.
* If a JS type custom param is marked mandatory, make sure that it’s not removed from the script that’s hosted else the bot will not load.