Every SDK, .env file and AI agent asks for the raw key, and once it exists in plaintext it gets pasted into a chat, committed to git, printed in a log, or handed to a contractor you'll never see again. Unseenkey keeps the key in an encrypted vault on your machine and hands out a handle instead. The handle looks like a key to whatever receives it, but it only works through the local broker, which swaps it for the real key at the last moment, checks a policy, scrubs the key out of the response, and writes every call to a tamper-evident log.
A leaked handle costs you nothing. A leaked key costs you until you notice.
Status: v0.1, alpha. Works and is tested on Windows, macOS and Linux. Not yet externally audited: use it with keys you can rotate. Delegating keys to other people through a hosted broker is designed, not built.
How it works
Two minutes with Claude Code
usk init # pick a password; write down the 24 recovery words
usk add anthropic # paste the key at a hidden prompt; provider detected, host-locked
usk env anthropic --policy chat # prints ANTHROPIC_BASE_URL + ANTHROPIC_API_KEY=usk_h_…
claude -p "hello" # Claude Code now calls Anthropic through the broker
usk log # every call, hash-chained
--shell powershell|cmd|dotenv prints the variables for your shell or .env. The daemon starts itself on first use, listens on loopback only, and locks after 15 minutes without a request or when the screen locks or the machine sleeps.
Or give your AI tools the tools, in one command:
usk mcp install
It finds Claude Code, Claude Desktop, Cursor and Windsurf on your computer and connects them, makes the vault first if you don't have one, offers to add your first key, and checks that the connection answers. Run it again whenever you like; it changes nothing that already works. Then restart the tool and ask it what API keys it can use. It calls APIs through Unseenkey and never sees a key.
Claude Code also has a plugin, if you'd rather install it that way. Use the plugin or usk mcp install, not both, or Claude Code gets the tools twice. The plugin needs Unseenkey 0.1.7 or later.
claude plugin marketplace add Bhagyesh97/unseenkey
claude plugin install unseenkey@unseenkey
What a handle can do
| |
|---|
| Policy per handle | Presets for each provider (stripe:payments = take payments, no refunds or payouts), explained in plain English. Expiry, request caps, time windows, approvals. |
| Hard caps | --cap 500/day: the 501st request is refused before it leaves the machine. Caps count requests, not money. |
| Canaries | --canary: a handle that never works. Plant it in .env.example; any use means someone has your files, and the vault locks. |
| Incident responses | A burst of refused requests throttles, pauses, asks you, or locks the vault — your choice per handle. |
| Approvals | Live prompts in the desktop app or usk approve: allow once, allow always, deny. |
| Camouflage | Handles shaped like the provider's own keys (sk-proj-usk-…) for SDKs that validate formats. Every format carries the usk marker. |
| AWS and OAuth2 | boto3, the AWS CLI and the JS SDK sign with a placeholder; the broker re-signs with the real key. OAuth2 refresh tokens stay in the vault; the broker keeps the access token fresh. |
| MCP server | usk mcp install, or the Claude Code plugin: the agent gets tools, never values. A tool connects itself on first use; taking over or reconnecting an existing one needs your password. |
| Projects | Group keys by the app that uses them. usk project protect (or "Protect a project" in the app) moves a folder's .env keys into the vault in one step; AI tools working in that folder see only its keys, and a daily request limit per project stops a runaway bill. |
.env guard | usk guard fix .env moves real keys into the vault and rewrites the file with handles. |
| Desktop app | Projects with a status panel, keys, agent access, approvals, activity with chain verification, one-click MCP setup, Windows Hello, signed auto-updates. |
More of the same:
usk handle create stripe --policy payments --expires-days 7 --cap 500/day # for a contractor: gone next week
usk handle create stripe --canary # a tripwire for .env.example
usk add aws-dev && usk env aws-dev # boto3 and the AWS CLI through the broker
usk add google-oauth # paste a refresh token or gcloud's ADC file
usk add gsc --file key.json --scope webmasters.readonly # a Google service account; the file stays in the vault
usk add twilio # keys in two parts: asks for each, or paste first:second
usk run --with DATABASE_URL=prod-db -- ./app # for what cannot be proxied (audited, scrubbed)
This is the beginning of the README. Read the rest at the original. Read the full README ↗
