Easy Guide to Uploading Documents on Vellum AI

Any document that you want to query against should be uploaded ahead of time at

What is a Document Index?

Document indexes act as a collection of documents grouped together for performing searches against for a specific use case. For example, if you are creating a chatbot to query against OpenAI’s help center documents, the text files of each article in the help center would be stored in one index. Here’s how it looks in Vellum’s UI:

Document Details

How to upload documents?

You can manually upload files through the UI or via API.

Upload Documents

Each document has a Name and an External ID which are initially populated with the name of the file that you upload.

Name - Human readable text which is how the document will be visible in Vellum’s UI (in documents tab)

External ID - As the contents of a document change and the old documents becomes out of date, you can submit the updated document for reindexing re-uploading it and specifying the same External ID.

Supported File Types

In addition to sending plain strings via API, Vellum also supports uploading files of the following types:

  • .txt
  • .pdf
  • .doc
  • .docx
  • .png
  • .csv

For all but .txt files, we will apply an OCR process to convert the file to a text representation. If you need another file type, please reach out!

Document Size Limits

Each document can be up to 32MB and 2.5M characters

Out-of-box Chunking Strategy

Vellum currently uses a static chunking strategy.

Chunking strategy: Overlapping windows w/ sentence splitting

Min overlap: 50%

Max characters: 1000

This configuration has proven to work well for most use cases. These settings will become configurable in future updates. Please reach out to if this chunking strategy doesn’t work for you and we can work on a solution for you.