How UnTangle reads your Drive
UnTangle only has read access to the folder you pick. The one thing it ever writes is the search index — and it writes it into a hidden application folder inside your own Google Drive, not to our servers.
Exactly what access you grant
When you connect Google Drive, Google's consent screen shows the permissions the app requests. UnTangle requests three Drive-related permissions. Here is what each one means in practice:
drive.readonly
Read-only access to your files
UnTangle can read the files in the folder you select — and nothing more. It cannot edit, rename, move, share or delete a single one of your documents. This permission has no write capability at all.
drive.file
Only files the app itself created
This scope lets the app see and update files that it created itself — in UnTangle's case, the index files. It does not give any access to your own documents beyond what the read-only scope allows.
drive.appdata
The hidden app folder (appDataFolder)
Google Drive gives every app a private, hidden folder inside your own Drive. This is the only place UnTangle ever writes. It stores the index there: a manifest of indexed files, the folder tree, and per-document text excerpts with their search vectors, all encrypted with a key derived for your account.
What this means for your documents
Because the read-only permission has no write capability, UnTangle is technically unable to modify the folder you index — not by accident and not by bug. The only write operation the app can perform against your Drive is creating or updating its own index files in the hidden application folder.
Those index files are readable only by the app and invisible in your normal Drive view. You can delete them at any time with the "Delete all my data" option in the app menu, or revoke UnTangle's access entirely from your Google account settings.
File types UnTangle can read
Only text can be indexed. Anything else in the folder is left alone, and after every update the app lists exactly which files it skipped and why.
- Google Docs
- Google Sheets
- Google Slides
- Excel (.xlsx, .xls)
- PDF (text-based)
- Plain text, Markdown, CSV, JSON, XML
Word (.docx), PowerPoint (.pptx), images and video are not read yet. Scanned PDFs hold pictures of text, not text, so they need OCR before they can be indexed — they are listed as skipped after each update.
The index mirrors the access you had
The index is built with your own Google authorisation, and the search then runs against that saved index. That means the index assumes you still have access to every file it covers. If a file is deleted, moved out of the folder, or a share is withdrawn, its excerpts stay in the index until the next update.
"Update index" resynchronises: files you can no longer open are removed and their index files are deleted from your Drive. Searches also verify the files behind an answer, so a result whose file is now gone or no longer shared is dropped from the answer and cleaned out of the index.
The flow, step by step
1. You pick a folder
After signing in with Google, you browse your Drive and select one folder — or use your whole Drive. UnTangle remembers the folder id — nothing is copied.
2. The folder is indexed, read-only
The app walks the folder recursively and reads each supported file: Google Docs, Sheets and Slides are exported as text, PDFs and plain text files are read directly. Indexing runs in batches, shows live progress, can be stopped, and picks up where it left off.
3. Excerpts and vectors are written to your hidden folder
The text is split into short excerpts and turned into search vectors (embeddings). These are encrypted and written back into the hidden appDataFolder inside your own Drive. At no point is document content stored on UnTangle's servers.
4. Questions only touch small excerpts
When you ask a question, the app ranks the files in the matching branch, opens only the most relevant ones, and sends the few best excerpts — together with your question, as separate messages — to the AI model. The model provider retains nothing.
Frequently asked questions
Does UnTangle copy or store my documents?+
No. Document content is never stored on UnTangle's servers. When a folder is indexed, the text excerpts and search vectors are written into a hidden application folder inside your own Google Drive, encrypted with a key derived for your account.
Can UnTangle change or delete my files?+
No. The Google permission UnTangle uses to read your documents is read-only, with no write capability at all. The only thing the app can ever write is its own index files, and only into its private hidden folder in your Drive.
Which file types can be indexed?+
Google Docs, Sheets and Slides, Microsoft Office files (Word, Excel, PowerPoint), PDFs and plain text formats such as .txt, .md, .json and .xml. Scanned PDFs are images and need OCR before their text can be read. Files of other types are skipped, and each indexing lists exactly which files were skipped and why.
How does UnTangle work?+
You connect a folder in your Google Drive and UnTangle builds a search index of it — text excerpts and search vectors stored in a hidden application folder inside your own Drive, not on our servers. When you ask a question, UnTangle searches the index for the most relevant passages, sends only those short excerpts to the AI model, and returns an answer with links to the exact files the answer came from.
What can I use UnTangle for?+
Anything where the answer is buried in your own documents: find where a decision was made across hundreds of meeting notes, ask what a project agreed last quarter, summarize a report, or find which file contains a specific number or policy. You ask in plain language instead of guessing file names or keywords, and every answer points back to the exact file it came from. Because access is read-only, you can point it at any folder without risk.
For the full data-handling picture — what little we store, where, and your GDPR rights — see Privacy & security, or go back to the start page.