Make a POST request to the new /services/data/vXX.X/tooling/composite resource to improve the performance of development tools or apps built with Tooling API. This new resource minimizes the number of round trips needed between the client and server by executing a series of Tooling API requests in a single call.
You can use the output of one request as the input to a subsequent request. The requests’ response bodies and HTTP statuses are returned in a single response body. The entire request counts as a single call toward your API limits.