In a Winter '14 Developer Edition and Spring '14 Pre-release I have noticed that using the Developer Console uses API calls. It looks like this affects third party tools like MavensMate as well. The limit for a Developer Edition is 5,000 / 24 hours and I've used about 125 in a 20 minute period. This is without running unit tests. Running unit tests burns through the API calls even quicker.
Add in another developer, code that uses the API, and frequent unit test execution and the limit can be hit without much effort.
Is there any configuration that I can make to not use as many API calls with the Developer Console? Perhaps, some features that I can disable?
It's possible that it is related to this Idea about the Tooling API and limits.
Best Answer
You can reduce your API usage by allowing your developer console session to "idle". Once idle, you'll only incur one API call per incident (such as saving a class, running a test). While not idle, the current implementation polls the server once every 6 seconds, or 10 API calls per minute while doing absolutely nothing.
Also, using the Force.com IDE will drastically reduce your API calls, because you won't suffer from the "monitoring" API calls. Believe it, it makes a big difference.
For those interested, I asked this myself on the Salesforce Community:
Josh Kaplan (SFDC PM) had this to say:
Presumably this applies to Spring '14.