2. A system, comprising: one or more processors; and memory storing instructions that, if executed by the one or more processors, cause the system to: receive user input corresponding to operations on a document, the one or more operations causing a change to an overlay of the document, the overlay containing user annotations to the document; transmit an application programming interface call to upload the overlay for the document having an identifier specified in the application programming interface call; receive, from a document management and collaboration system, a second document identifier corresponding to a version of the document which corresponds to the overlay; receive a request for collaboration on the document; obtain the document and the overlay by transmitting a second application programming interface call that specifies the second document identifier; and transmit the obtained document and the overlay to one or more collaborators for collaboration.
2. A system, comprising: one or more processors; and memory storing instructions that, if executed by the one or more processors, cause the system to: receive user input corresponding to operations on a document, the one or more operations causing a change to an overlay of the document, the overlay containing user annotations to the document; transmit an application programming interface call to upload the overlay for the document having an identifier specified in the application programming interface call; receive, from a document management and collaboration system, a second document identifier corresponding to a version of the document which corresponds to the overlay; receive a request for collaboration on the document; obtain the document and the overlay by transmitting a second application programming interface call that specifies the second document identifier; and transmit the obtained document and the overlay to one or more collaborators for collaboration. 11. The system of claim 2 , wherein the instructions further comprise instructions that, if executed by the one or more processors, cause the system to transmit another application programming interface call that specifies text and document coordinates corresponding to a location of the text in the document to be inserted into the document by the document management and collaboration system.