14 open-source UI components for document-processing AI agents
Extend.ai has released 14 UI components — including PDF, Word, and Excel viewers — as free open-source software. They help developers build user-facing screens for document-processing AI agents much faster. The MIT license means anyone can use them commercially at no cost.
Extend.ai built these components for their own document processing service and decided to open-source them after customer demand. The kit includes viewers for PDF, DOCX, and XLSX files, plus file upload, e-signature, and bounding box citations — a feature that visually highlights exactly which part of a document an AI referred to when giving an answer. The team says they have fixed many tricky edge cases encountered while running millions of pages per day through their own system.
For anyone building AI agents that read or analyze documents, this kit removes the need to build file viewers from scratch. It is particularly useful for document intake flows (where users upload files for an agent to process) and internal tooling, cutting down development time significantly.
Key points
- 14 components covering PDF, Word, and Excel viewers released under MIT license (free for commercial use)
- Includes bounding box citations so users can see exactly where an AI sourced its answer in a document
- Also covers file upload and e-signature — common needs in document workflows
- Battle-tested at millions of pages per day in production
- Speeds up building the user-facing side of document-processing AI agents
Quick term guide
- components
- Ready-made, reusable pieces of a user interface — like a file viewer or upload button — that developers plug into their app.
- open-source software
- Software that is free for anyone to use, view, and change.
- open-source
- Software whose code is shared publicly so others can inspect, use, or change it.
- developers
- Developers are people who build software, apps, or websites.
- MIT license
- A permissive license that usually allows broad reuse if basic conditions are kept.
- bounding box citations
- A visual highlight (a rectangle) drawn on a document to show exactly which section an AI used when answering a question.
- edge cases
- Unusual or unexpected inputs that fall outside the normal, expected use of a product.
- production
- The live version of a service that real users use.