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Vespper Logo
Backed byY CombinatorCombinator

The AI for regulatoryand technical documents

Upload your source data. Get a first draft with tracked changes and source-linked citations; ready for review

Vespper document editor preview
From founders and investors that come from:
Viz.ai
Google
Y Combinator
Snyk
The Problem
Writing tools were not built for modern document work.
Professionals spend hours producing and updating documentsbuilt from scattered source material, but their tools have not caught up.

AI works on snippets, fails on real documents

Most AI assistants are not built for long documents. They lose context across sections, create contradictions, and fail to apply updates consistently in complex reports.

It’s hard to verify generated content

Existing solutions dont show end-to-end traceability.

Output of currently tools generate bad formatting & broken doc structure

You manually stitch changes across sections and versions.

It's hard to iteratively work on documents

Most AI tools do not give you clear, reviewable edits with full control

Solution
Intelligent document editor for serious work.
Supported by human-in-the-loop oversight.

Fetch any piece of content from your source material

Reduces prompt iteration by attaching granular source context directly to each instruction.

@
📎
OECD test guidelines 429.pdf
12656 tokens
📎
Research_Paper_2024.pdf
8432 tokens
📄
Laboratory_Protocol_v3.docx
5821 tokens
📊
Clinical_Trial_Data.xlsx
15234 tokens

Create standardised documents from examples

Upload previous reports and templates as examples. Vespper can generate standardised documents that match your standards automatically.

Motion to Compel ...
Template • Word Doc...
Defendant Discove...
PDF Document
Meet and Confer C...
PDF Document

Motion to Compel Further Discovery Responses

I. Introduction

Plaintiff TechStart Solutions, LLC ("Plaintiff"), by and through...

Run the AI block or start writing your content here...

Draft the introduction section for this Motion to Compel. State...

Full traceability with source-linked citations

Every statement can be traced back to the underlying evidence. Vespper generates citations that link directly to the exact source passage so outputs are defensible.

end of year invoices.xlsx
"$200"
end of yea..

Make changes to your document and see whats changed

Every change is clear and easy to review so teams can confidently verify edits before submitting, especially when accuracy and auditability matter.

Results

At T=24h, IL-6 measured 750 pg/mL525 pg/mL in treatment group (n=12). Mean AUC was 0.820.78 ± 0.04 µg·h/mL.

Control arm: IL-6 was 410 pg/mL385 pg/mL (n=11), AUC 0.610.58 ± 0.03 µg·h/mL.

Integrations

Connect your source data

Upload files directly or connect to cloud storage and knowledge bases

DOCX
XLSX
Markdown
Google DriveGoogle Drive
DropboxDropbox
SharePointSharePoint
S3S3
ConfluenceConfluence
NotionNotion
Document360Document360
BookStackBookStack
GitBookGitBook
MediaWikiMediaWiki
Security
Private by default. Flexible when you need it.
SOC 2 Type IISOC 2 Type II (In Progress)
GDPR CompliantGDPR Compliant

We do not train on your data

Your documents are never used to train AI models.

Private by default

Your documents stay private to your workspace.

Bring your own LLM

Use your preferred provider, including self-hosted models.

Private deployments

VPC and on-prem options available on request.

Audit-friendly history

Complete version history with tracked diffs.

Fastest setup

Cloud app + public LLMs

We use our cloud app together with public LLM vendors (OpenAI, Anthropic, etc.). Safe for many customers, but since the model sits with the vendor, this is not ideal for highly proprietary R&D data.

Balanced

Cloud app + private LLMs in your cloud

We use our cloud app and configure it to use LLM running inside your AWS/GCP/Azure account (Bedrock, Vertex, Azure OpenAI). Your data never leaves your environment when it hits the model. We also offer to help spinning those models ourselves as a service.

Maximum security

Fully self-hosted

We deploy both our app and the LLMs entirely inside your cloud. Nothing touches our infrastructure. Strongest option, but requires more setup time and resources.

Our cloud environment

Your Documents
Vespper

Editor + Diffs

OpenAI
Anthropic
Gemini

External LLM vendors

Third-party opinions
Don't take our word for it.
Pick your favorite AI and ask what it thinks about Vespper. No filter, no spin.

These links open the AI of your choice with a pre-filled question about Vespper.

Start editing with Vespper in minutes.
Write, revise, and review professional documents
with full visibility and control.
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The AI editor for professional documents