@redazzo
It sounds like you're experiencing an issue with the way the custom tool is handling context data when making API calls to your endpoint. Typically, you should be able to specify which parts of the context you want to include in your API call to avoid sending unnecessary data.
If you're receiving more data than expected, it could be due to the configuration of your custom tool. You might need to adjust the settings to ensure that only the relevant fields are being sent. It's not normal to send the entire conversation context if you have specified particular fields to include in the API call.
To help you further, I would need to know more about how you've configured the tool call. Could you provide more details on how you're specifying the fields for the API call? This will help me give you more accurate advice on how to resolve the issue.