This one is a little too long for a social media post so have it in a small blog
On the 26th of February Microsoft announced a little change to how many API calls can be made per user per 5 minute period. This is limited at 60,000 requests in 5 minutes............ This initially took the community by surprise but standing back as we didn't know if calls from within the application would count or if 3rd party tools like Resco could hit that limit by 9:05 each morning.
So here is the clarification on what is included from within D365 and will not count towards that limit.
On top of this if you have written multiple calls using parallel requests within 1 execution it will only count as 1 call.
And for Resco - You'll be glad to know that all calls from Resco (out of the box or with customisations) are classed as "Internal Calls" and will not use your limit, So rest easy if you have 50,000 engineers syncing all the jobs for the day to their mobile device.
If you are unsure how many calls you have then it might be worth checking Organisation Insights out as it can give you an overview of your usage.
Now you are asking what does count towards those calls? I am told that it is only requests that are going Inwards to the system, This hopefully alleviates the fear and becomes a non issue for most people