Stop pasting confidential files into chatbots
Dec 18, 2025
🛑 Stop pasting confidential files into chatbots
Browser chatbots are amazing. They are also the fastest way to accidentally move confidential work onto someone else’s servers.
It happens every day:
A contract clause gets pasted “just to summarize”
A customer email thread gets uploaded “just to find the decision”
A spreadsheet screenshot gets shared “just to pull the numbers”
For most casual use, that risk is acceptable. For work, especially client work, finance, legal, and internal strategy, it is often not.
This article is a practical playbook for using AI at work without leaking confidential files. It covers what to avoid with tools like ChatGPT, Google Gemini, and Anthropic Claude, and what to do instead on a Mac when privacy actually matters.
If you want private AI that runs where your files live, Fenn is built for that. Find the moment, not the file.
The uncomfortable truth about browser chatbots
When you use ChatGPT, Gemini, or Claude in a browser or hosted app, the core architecture is the same:
Your prompt is sent to a remote server
The model runs there
The provider may store logs for safety, debugging, and product improvement
In legal disputes, providers can be asked to preserve, produce, or sample data under court orders, even with protections in place
That does not mean those companies are careless. It means your “conversation” is not physically on your Mac. It exists in infrastructure you do not control.
If you work with confidential data, the right question is not “do I trust them.” It is:
Do I want my client contracts and internal documents on any third party servers at all?
For many industries, the answer is no.
What counts as confidential, in real life
People often think “confidential” means secret government files. In business, it is much more common.
Examples:
Contracts, NDAs, DPAs, MSAs, SOWs
Pricing terms, discounts, renewal clauses
Customer lists, pipeline, revenue numbers
Board decks, investor updates, fundraising materials
Legal strategy notes, dispute timelines
Payroll, vendor agreements, bank statements
Product roadmaps and unreleased features
Internal incident reports, security reviews
Screenshots that show private dashboards or user data
If you would not want it forwarded outside your company, do not paste it into a cloud chatbot.
The three common ways people leak data to chatbots
1. Copy paste “just this one paragraph”
This is the most common. A clause, an email, a number.
The risk: it is still a disclosure, and it is stored and processed off device.
2. Uploading entire PDFs for analysis
Contracts, board decks, finance exports, research papers.
The risk: it is convenient, but you just moved a lot of sensitive context to a third party.
3. Screenshots and images
People forget images can contain:
Names, emails, phone numbers
Internal dashboards and metrics
Hidden context in the UI
Text that is easy for models to read
The risk: images feel “less searchable,” so people are less careful.
A safer AI workflow on Mac
You do not need to stop using cloud AI completely. You need a boundary.
A simple rule that works:
Use cloud chatbots for public knowledge, brainstorming, and generic questions
Use local AI for anything that touches confidential files
That boundary lets you keep the speed of AI while removing the biggest risk.
The rest of this guide shows how to do that.
What to use cloud AI for, safely
Cloud models are great when the prompt is not sensitive.
Safe examples:
Writing a first draft of a blog post with no internal data
Asking for help with a coding error message you can redact
Learning a concept, summarizing public articles, brainstorming ideas
Improving wording without pasting proprietary details
If it can be answered without your company’s private files, keep it in the cloud.
What to keep local, always
If your prompt depends on your internal files, keep it on your Mac.
Examples:
“Summarize this customer contract and highlight renewal terms”
“Find where the board deck mentions runway assumptions”
“Which invoices from this vendor are above 500 dollars”
“Locate the email where the customer approved the new pricing”
These are not internet questions. These are “my files” questions.
They belong on device.
Private by design: how Fenn avoids the cloud risk
Fenn is an AI powered file search engine for macOS that is built around privacy by default.
The model is simple:
You choose folders and sources to index
Fenn indexes your content on device
You search or chat with your own files
You open the underlying files yourself to verify
What makes this different from browser chatbots is where the work happens.
Your files stay on your Mac
Your search and chat runs locally
No uploads of your archive to a vendor server
You do not have to trust a privacy policy, because you can test it yourself
A practical proof:
Once your models are downloaded and your files are indexed, you can turn Wi Fi off and keep working. If it works offline, your data is not being sent to a cloud model.
That is what “private by design” looks like.
Find the moment, not the file.
What you can do with Fenn instead of pasting into ChatGPT
Search across documents and media
Fenn can search across:
PDFs and long documents
Text inside images and screenshots
Apple Mail messages stored on your Mac
Notes and internal docs
Audio and video with useful timestamps
Instead of pasting content into a chatbot, you ask Fenn to find it inside your archive.
Use precise search modes when you want control
Fenn includes:
Semantic mode for natural language intent
Keyword mode for exact terms
Hybrid mode for both
Exact mode for strict literal matches
This is how you avoid the “scroll forever” workflow and jump to the place that matters.
Use Chat mode when you want answers, not file results
With Fenn chat you can ask questions in plain language about your indexed files, and follow up in a conversation.
Examples:
“Which contracts auto renew and require 60 days notice”
“Summarize the last three board updates on churn and runway”
“Find approvals for the pricing change in Apple Mail and list who said yes”
The difference is not the UI. It is the architecture. It stays on your Mac.
A practical checklist to stay safe with AI at work
If you want to adopt AI without regret, use this checklist.
Before you paste anything into a cloud chatbot
Would I share this with an external vendor by email
Does it contain client or employee data
Does it include pricing, legal terms, or internal metrics
Would it harm us if it showed up in a legal discovery process
If any answer is yes, keep it local.
Redaction rules that actually help
If you must use a cloud tool:
Remove names and emails
Replace customer names with placeholders
Remove pricing and contract terms
Crop screenshots to remove account details
Do not paste whole documents
Redaction is not perfect, but it is better than full disclosure.
Your default should be local for work files
If the question is about your contracts, decks, invoices, Mail, or screenshots, use a local tool first.
How to get started with Fenn in one hour
You do not need to index your entire life.
Start with your highest value, highest risk folders:
Install Fenn on an Apple silicon Mac (Sonoma 14 or later is recommended).
Add sources like Contracts, Finance, Projects, Research, Screenshots, and Apple Mail storage.
Let Fenn index on device.
Test with Wi Fi off to confirm your workflow is local.
Use search modes for quick jumps, and Chat mode for multi step questions.
From there, expand your sources gradually.
Pricing
If you handle confidential work on a Mac, the safest AI workflow is the one that never uploads it.
Local, 9 USD per month, billed annually
On device indexing. Semantic and keyword search. 1 Mac. Updates. Founder support.Lifetime, 199 USD one time
On device indexing. Semantic and keyword search. 1 year of updates. 1 Mac. Founder support.
Stop pasting your private work into the cloud. Keep it on your Mac.
Download Fenn for Mac. Private on device. Find the moment, not the file.