BibTeX (.bib) or XML exported from EBSCO. Select several files to combine them; duplicates (same DOI, or same title) are removed. UTF-8, up to 10 MB in total. Your entries are kept for one hour so you can re-rank and export, then deleted.

One keyword: weight per line. Keywords match whole words; add * to match a prefix (steel* also matches "steelmaking"). Negative weights push entries down.

One sentence, English works best. Each entry's title and abstract get a similarity score from 0 to 1, which finds relevant papers even when they don't use your keywords. Up to 300 entries per file; the first run on a file can take a while.