Keyline: An AI Reading Assistant for Your PDFs and Docs

Keyline is an AI reading assistant for your PDFs and Office documents. Upload a file and Keyline reads every page as an image, taking in the figures, diagrams, and tables along with the text. Ask a question and the answer comes back cited to the block it came from, with the page number and a cropped image of that block.

Keyline is built for the moments when you need an answer from inside a document, or from across a whole library of documents, faster than reading page by page.

Two ways in

One engine reads your documents, and there are two ways to reach it. Every page in this documentation is written for one of them, and says which at the top.

• The Keyline app is the hosted interface you sign in to. You upload files into a library, read them in the PDF view, and ask questions in a conversation panel beside the page. Keyline renders the answer, the page it came from, and the cropped block behind it. The product page for teams covers what it is and how teams put it to work.
• The Keyline API is the same retrieval engine over HTTP, with no interface of its own. Your agent, your application, or your internal tool makes the call and receives text, page numbers, and image crops to render inside the interface you already ship. Keyline for developers carries that argument.

The two share a corpus rather than holding separate ones: an API call is scoped by a project id you copy out of the app's project settings page. Where the app says library, the API says project.

What Keyline can do

• Read a single document deeply. Keyline understands page layout, figures, diagrams, and tables, so a question about a chart gets a real answer.
• Answer with citations. Every claim comes back with its page number and a cropped image of the block behind it, so you can verify it in seconds.
• Search across many files at once. A multi-file search index lets you ask a question once and get results pulled from every relevant document in your library.
• Stay organized. Libraries and bundles keep your uploaded files grouped so you can find and reuse the right set later.

Using the app

• Getting started: upload your first document and see what happens next.
• Reading and analyzing PDFs: the PDF view, page navigation, and how Keyline reads figures and tables.
• Conversations and citations: asking questions and following an answer back to its source.
• Searching across multiple files: asking one question across your whole library.
• Organizing your library: libraries and bundles.

Building on the API

• Keyline API quickstart: your first cited answer over HTTP, and putting your own documents in.
• The agent runbook: the whole API contract on one page, written for a coding agent to read in a single pass.

Both surfaces

• FAQ: file types, size limits, sharing, languages, the API, and troubleshooting.