PubMed/NCBI (ESearch→ESummary/EFetch pipeline; count is string; ELink broken 2026; CollectiveName branch),
CrossRef (title/container-title always lists; abstract has JATS XML tags; type=proceedings-article not conference-paper),
OpenAlex (abstract_inverted_index reconstruction; cursor >10K pages; group_by not group-by; concepts deprecated use topics),
FRED (fredgraph.csv timeouts headlessly; API needs free key; BLS/WorldBank/AlphaVantage as keyless alternatives),
MusicBrainz (Mozilla/5.0 gets 403; recording length in ms; CAA front flag vs types array differ).
sauravpanda