Pre-1.0Permissions for local AI tools
Don't give AI agents your whole computer.
Warden gives AI tools and MCP servers access only to the files, secrets, and network hosts you approve. Everything else is blocked by default.
npm install -g warden-sandbox-cliLinux · macOS · Windows · Docker fallback · MIT
Recorded terminal session · verify the boundary on your own host
The problem
AI tools run with your permissions.
A local agent or MCP server can inherit access to files, environment values, and network destinations available to the user who started it. Warden turns that implicit access into explicit policy.
Files
Keep project access separate from credentials and unrelated folders.
Secrets
Pass only the environment names a tool actually needs.
Network
Allow specific APIs and block undeclared destinations.
Interactive illustration
Same tool. Smaller boundary.
Local tools normally run with your user permissions. Choose a request and toggle Warden to explore an explicit allowlist. This illustration is not a live security test.
AI agent
mcp client
fs.read
WARDEN
./workspace
granted
./workspace/data.json
● evaluating fs.read at the boundary…
Audit log
agent connecting…
0
allowed
0
denied
0
exposed
New · AI agent workspace
Let the agent edit code. Keep credentials out of sight.
Warden gives Claude, Codex, OpenCode, or another local coding tool a temporary sanitized project. The agent can work on the code it needs without receiving the values you declare as protected.
Hide selected values. Environment names and file fields become opaque placeholders.
Review before applying. Warden shows sanitized changes and waits for your approval.
Fail safely. Failed sessions, tampered placeholders, and rejected reviews leave the host unchanged.
agent:
workspace: ./project
redaction:
apply: review
env: [OPENAI_API_KEY]
files:
- path: .env
format: dotenv
fields: [DATABASE_URL]Agent sees
DATABASE_URL=<WARDEN_HIDDEN>
OPENAI_API_KEY=<WARDEN_HIDDEN>
Host changes
sanitized diff
human approval
One policy
Define what the tool needs.
Everything not listed stays outside the sandbox. Keep the first policy small, run it, then expand only when the audit shows a real need.
Explore the policy reference →filesystem:
read:
- ./project
network:
allow:
- api.github.com
env:
allow:
- GITHUB_TOKENProof, not promises
See how Warden is verified.
The project publishes compatibility fixtures, sandbox proof harnesses, and platform-specific limitations. Verification maturity differs by operating system.
18
MCP fixtures
14
pass
4
backend paths
Start with one local tool.
Install Warden, define what your tool needs, and keep everything else outside the boundary.
npm install -g warden-sandbox-cli