The cards above are the short version: one line, one job. The pages behind them are where the mechanics live. Local tools — merge, split, rotate, organize, sign, JPG to PDF, and the image exports — run in the browser on the file you picked. Compress, lock, and unlock also run in the browser, but they rebuild pages as JPEGs, so the download is not the same object stream you started with. Translate, summarize, chat, OCR, and the career writers call /api/ai or /api/ocr on the Cloudflare Worker. That Worker forwards text (capped at 30,000 characters) or a page image to a model and returns the completion. It does not write the prompt into a database.

The site itself is served on https://pdfswift.cc. HTTP and the www host 301 to that HTTPS URL, so the page and the script tags travel under TLS. TLS protects the connection. It is not a second password on your PDF. If a tool never POSTs the file, there is no copy on a PDFSwift disk to delete later.

Picking a tool without guessing

If you can drag a highlight across a sentence, the PDF has a text layer. Merge, split, rotate, and organize keep that layer because they copy page objects with pdf-lib. PDF to Word can read it. If the highlight draws a box around a picture, you have a scan: Word will come back empty until OCR, and chat will be chatting with nothing.

Need a smaller email attachment and you can live without selectable text? Compress, and keep the uncompressed file. Need a password on a file people only have to view? Lock, knowing the pages become pictures. Need the original text after you already know the password? Open it in a reader that decrypts in place, or accept that Unlock here photographs the pages.

AI buttons are for text you are willing to send. Merge is not. The logo is one brand. The buttons are two pipelines. Read the tool page before you drop a client file, and use the one-line card only as a label.

What the Worker will and will not keep

Text sent to /api/ai is cut at 30,000 characters. A question is cut at 4,000. The completion is requested with a ceiling around 1,800 tokens. OCR posts the page image to /api/ocr instead. In both cases the Worker returns JSON and does not write the body into a database or a file bucket. That is not the same sentence as “nobody else saw it.” The model that answered saw the slice you sent. Local tools never construct that request.

There is no account, so there is no dashboard that lists yesterday’s contracts. The download folder on your machine is the archive. Name files for the step: -merged, -email, -locked, -unlocked-working. A folder of document.pdf copies is how a JPEG stack gets mailed as the original.

If a page looks empty of explanation, it is the wrong page. Every tool route under this list carries the mechanism, the limits, and the questions for that button. The cards stay one line so you can find the button. The route is where the behavior is written down.