Review Comment:
This manuscript addresses a relevant topic for the Semantic Web community, namely Semantic Artefact Catalogues (SACs), their technologies, disciplinary coverage, and their possible role in supporting FAIR semantic artefacts. I appreciate the effort involved in collecting a large number of SACs and in making an associated dataset available. However, I do not think the manuscript currently meets the expectations for a publishable survey article.
My main concern is that the manuscript is primarily an inventory of resources rather than a survey that offers substantial synthesis, critical analysis, or clear scientific insight. The work is extensive, but the contribution remains largely descriptive. After reading the manuscript, it is not sufficiently clear what new understanding the Semantic Web community gains beyond the observation that the SAC landscape is broad, fragmented, heterogeneous, and unevenly mature. These are useful observations, but they are not developed into strong, actionable, or conceptually significant conclusions.
1. Suitability as introductory text
As an introductory text for researchers, PhD students, or practitioners, the manuscript is only partially successful. It provides useful background and many examples, but it is too long, too descriptive, and not sufficiently structured around the needs of newcomers to the topic. A reader looking for an entry point into SACs may find the manuscript difficult to navigate because the core concepts, main system families, and practical implications are not sufficiently distilled.
A survey article should help readers understand the field, its conceptual structure, key debates, open problems, and decision points. In its current form, the manuscript mostly documents what exists. It does not sufficiently explain what lessons should be drawn from the inventory, what choices practitioners should make, or how the field should move forward.
2. Comprehensiveness and balance
The manuscript is comprehensive in the sense that it collects and classifies a large number of SACs. This is a strength. However, comprehensiveness alone is not enough for a survey article. The paper would need a more balanced and critical treatment of the material.
The review does not appear to follow a sufficiently systematic and reproducible protocol. The collection process relies substantially on author expertise, known sources, project networks, technology providers, and manual judgement. While this may be acceptable for an exploratory mapping exercise, it weakens the claim of a comprehensive scientific survey. The manuscript should not overstate the generality of its findings when the data collection and assessment procedures are partly informal and expert-driven.
This issue is particularly important for the FAIR-enabling assessment. The assessment is conducted only on a subset of active SACs, selected because the authors had direct expertise as providers, maintainers, or long-term users. This makes the results useful as informed observations, but not as a balanced or representative assessment of the whole landscape. The coarse-grained nature of the evaluation also limits the depth of the conclusions that can be drawn.
3. Readability and clarity
The manuscript is too long for the level of insight it provides. Several sections read like a project deliverable or technical report rather than a focused survey article. The historical background, technology descriptions, methodological details, and descriptive results could be substantially shortened or moved to supplementary material.
The main text does not sufficiently distinguish between essential findings and supporting details. The result is that the paper provides a large amount of information, but the argument remains diffuse. The conclusions mostly restate broad and expected points: fragmentation, heterogeneity, need for interoperability, and need for better FAIR support. These conclusions are valid, but not sufficiently novel or specific to justify the length and level of detail of the manuscript.
4. Importance to the broader Semantic Web community
The topic is important, but the manuscript does not yet demonstrate a sufficiently strong contribution to the broader Semantic Web community. The most valuable output appears to be the dataset, not the paper itself. The article should provide interpretation, conceptual framing, and actionable recommendations that go beyond the dataset. At present, the manuscript does not sufficiently answer the “so what?” question.
For example, the paper could have provided clearer answers to questions such as: Which SAC technologies are most sustainable and why? Which communities should consolidate rather than create new catalogues? What minimum FAIR-enabling capabilities should all SACs provide? Which forms of interoperability should be prioritised? Which types of duplication are harmful, and which are acceptable? Without stronger answers to such questions, the paper remains mainly descriptive.
Assessment of the data file provided under “Long-term stable URL for resources”
The authors provide a dataset through Zenodo, which is an appropriate repository for long-term preservation and discoverability. However, the data package appears insufficiently documented. I could not identify a separate README file explaining the structure of the spreadsheet, the meaning of the fields, the coding decisions, the assessment procedure, or the limitations of the data.
The spreadsheet is useful as an inventory, but it is not sufficient for replication. To reproduce the study, one would need a clearer protocol for identifying SACs, deduplicating entries, assigning status/type/discipline/technology labels, and performing the FAIR-enabling assessment. The FAIR-enabling evaluation especially depends on expert judgement, and the dataset should provide more provenance and justification for the assigned levels.
The data artifacts therefore appear incomplete. At minimum, the authors should provide a README, a data dictionary, a frozen version of the dataset used for the manuscript, scripts or notebooks used to generate the reported figures and statistics, and documentation of the assessment process.
| 
