More of your PDFs are now read by software before a person sees them: AI assistants summarising attachments, search tools answering questions over a document library, and agents filling in forms or comparing contracts. When those tools get a document wrong, the cause is usually the file, not the model.
The good news is that the habits that help AI are the same ones that make PDFs accessible to people using screen readers.
1. Export from the source, do not scan
A PDF exported from Word, Google Docs or a design tool contains real text. A scan contains a picture of text, which the AI must OCR first, adding errors. If you have the source file, export it. If you only have paper, scan at 300 DPI and run OCR. See scanning resolution for documents.
2. Use real headings
Headings created with heading styles become structure in a tagged PDF. Bold, larger text that only looks like a heading is just text. Structure helps AI tools split a long document into sensible sections instead of cutting across topics. See tagged vs untagged PDFs.
3. Keep tables simple
Merged cells, tables split across pages, and tables made from tab stops are where extraction breaks most often. Use one header row, no merged cells, and a real table object. If a table is critical, include the data in a spreadsheet as well. See extracting tables from PDFs with AI.
4. Fix reading order in multi-column layouts
Two-column layouts, sidebars and pull quotes can be read in the wrong order, so a sentence from the sidebar ends up in the middle of a paragraph. Tagged PDFs carry a reading order; check it. See reading order in tagged PDFs.
5. Write alt text for charts and diagrams
Multimodal models can look at images, but a one-sentence description of what a chart shows ("Revenue grew 18% in Q3, driven by Europe") removes guesswork. It helps screen reader users too. See how to add alt text to PDF images.
6. Do not hide text
White text, text behind images and hidden layers are read by software even when people cannot see them. Sometimes that is an innocent leftover from a template; sometimes it is prompt injection. Either way, the AI sees content the human reader did not.
7. Fill in the metadata
A real title, author and language in the document properties help search tools and assistants identify the file. "Microsoft Word - Document1" is not a title. See how to edit PDF metadata.
What about flattening?
Flattening form fields and annotations into the page makes a document look final, but some flattening tools turn text into images. Check that text is still selectable after flattening. If it is not, AI tools will need OCR again. See how to flatten a PDF.
A quick test
Before sending an important PDF, copy all the text and paste it into a plain text editor. If it reads cleanly, in the right order, with nothing unexpected, an AI tool will read it well too.
Takeaway
AI tools are only as good as the documents they are given. Real text, real headings, simple tables and honest content serve the models and your human readers at once. For editing tasks after export, Docento.app works in the browser without uploading your files.
