The test that matters most
Everything needed to check the Redline page yourself.
Compare a document with itself
A tool that compares contracts has one unforgivable failure: reporting a change that is not there. So the first test is to feed it the same file twice. The answer must be exactly zero changes — not "almost none".
| pair | changes reported |
|---|---|
| a research paper against itself (527 lines) | 0 |
| a tax form against itself (144 lines) | 0 |
Real revisions, revised by people
The other four pairs are genuine versions of the same document: two research papers whose authors published later revisions, and two tax forms a year apart — the hard case, because a revised contract changes two lines, not a hundred.
| pair | changed | removed | added | untouched |
|---|---|---|---|---|
| paper, v1 → v5 | 105 | 54 | 85 | 368 |
| paper, v1 → v2 | 250 | 448 | 577 | 36 |
| tax form, 2025 → 2026 | 47 | 0 | 11 | 86 |
| tax form, 2024 → 2026 | 4 | 0 | 0 | 65 |
Full output: medicao.jsonl. The second pair is the honest embarrassment: only 36 lines survive untouched, because that document was re-typeset between versions and almost every line moved. Redline says so on screen instead of pretending the document was rewritten.
Repeat it
sh buscar.sh ./pares # fetches the eight documents npm install playwright node banco.js path/to/app.html ./pares