The Task (T) 5.1 of the CRAFT-OA project addresses the topic of the academic publications indexing from the point of view of the publishers, especially the Open Access Diamond Journals (OADJs). OADJs do not always match the requirements of the main indexing services, either because of their own technical capacities, or because of the biases of the indexes. The task’s objective is to help OADJs to know more about the indexes’ requirements and to better understand the global landscape of academic publications indexing. The main output of the task will be a synthetic documentation about a large set of indexing services, containing structured and comparable information, alongside useful links to more in-depth technical documentation. In this way, the T5.1 documentation will help OADJs to improve both their knowledge of technical requirements and their awareness of all the indexing possibilities for their contents. In particular, the documentation will bring a clearer identification of the different types of services concretely operating academic publications indexing (e.g., search engines, catalogues, directories, etc.). Furthermore, the extensive documentation will describe the indexing services based not only on prestige criteria, but also, for instance, on interoperability, additional services, or bibliodiversity criteria. In order to build the documentation, the T5.1 started with the analysis of existing academic indexes lists to extract useful analytical categories. This work resulted in a Knowledge Base (KB) about a first series of indexes, using an identical structure for all the indexes. This set of organized information served then as a source for the creation of the documentation itself. The documentation aims at presenting the information stored in the KB in a more user-friendly and explicit way, corresponding to either explanation of the KB content, or selection within this content. The current work represents a first version of the documentation, which will be refined and finalized until the end of the project. The documentation, and potentially the KB, are meant to be integrated in the Living handbook that is being currently developed by CRAFT-OA Work Package (WP) 7. This deliverable is currently under review by the EC.