Productivity

Nonce: Least-Privilege Access for AI Agents

Nonce gives AI apps least-privilege passes to your Gmail, calendar, files, and Slack, with phone approvals for sensitive requests and prompt-injection checks.

Nonce gives AI apps a pass, not your keys. It sits between your AI apps and your email, calendar, files, and Slack, and every request for your data goes through a policy-controlled layer. Each question gets a pass to just what it needs, and the pass expires on its own. It launched on Hacker News on November 1, 2026.

The model is least privilege by default. When an app asks for access, Nonce turns your question into a filter, for example emails from united.com about boarding. The app can search inside that filter but cannot see past it. Anything that touches money, health, passwords, or sign-in codes, or anything that looks off, waits for your approval, and you get a notification on your phone to allow it with one tap or ignore it so the app gets nothing.

Key features

Least-privilege passes: each pass covers only what the question needs, and expires automatically. Requests for everything at once, or for more than 24 hours, are blocked in every mode.
Three carefulness modes: Cautious, Standard, and Relaxed, set per AI app and changeable anytime.
Phone approvals: sensitive requests come to your phone with one-tap allow, plus offline hours when nothing goes through on its own.
Prompt-injection checks: Nonce checks what an app is about to read for instructions aimed at the AI. If it finds some, the app gets the sender and subject but not the body, and you get an alert.
Read-only connectors: Gmail, Calendar, Drive, and Slack connect read-only, with support for your own connectors.
Stop button: every pass has a Stop button, on your phone and on the web.
Wide app support: works with ChatGPT, Claude, and Cursor via MCP connectors, plus a key option for apps that cannot sign in.

Who it is for

Nonce is for anyone who wants AI assistants working with their inbox, calendar, files, and Slack without handing over the keys. If you have hesitated to connect Gmail to an AI app because the access felt too broad, this is the product built for that exact concern.