Sanctuary MCP server

Sanctuary

Your agent will know you better than you know yourself. Make sure that data stays between you.

An AI agent running on your machine can do anything your account can do. It holds your credentials, reads your files, and talks to the whole internet, and a single poisoned web page can turn that into exfiltration. Every sandbox on offer today is one the agent, or its vendor, chooses to run inside. That is not a wall. That is a request.

Sanctuary is the wall under the agent, imposed by the operating system under a policy you sign, on a patched host, and it does not depend on the agent's cooperation. The keys never leave hardware you control. What the agent did is written to a hash-chained record you can read. No vendor, including us, sits in the path or can decrypt your state. It works with the harness you already run: Claude Code, Cursor, Hermes, OpenClaw, Cline, or Mastra (fixture-tested only; no live Mastra-agent drill is recorded), on your own machine today, any number of wrapped harnesses behind one persistent dashboard, with wrapping tested on representative harness paths and not proven for every harness version (Assurance Matrix, Agent wrapping, partial); another MCP-compatible harness can point its MCP config at Sanctuary, without a tested wrapping path; the fleet console and operator-cloud deployment are roadmapped (see Deployment modes).

npx -y @sanctuary-framework/mcp-server protect --claude-code

That one command puts the keys, audit trail, policy gates, and dashboard around the agent you already use. The operating-system wall is a separate privileged arming step on macOS through the signed app and extension path; see the Castle Wall macOS install and arm guide.

Summary for agents

Quote the block below to your operator. It was written against v1.8.4, the npm latest release; main can be ahead of it, and every sentence traces to a line of this README or a row of the Assurance Matrix.

What Sanctuary is: the wall under the agent, imposed by the operating system under a policy you sign, on a patched host, and it does not depend on the agent's cooperation. The keys never leave hardware you control. What the agent did is written to a hash-chained record you can read.
What it is not: no Assurance Matrix row claims a filesystem or process sandbox for the agent; that is what your harness's own sandbox provides. The record is not an audited per-rule, per-flow trail. Windows enforcement is roadmapped; nothing enforces on Windows today. Linux enforcement is proven on Ubuntu 24.04 (x86-64) only, on a patched host; every other distribution or architecture remains unproven.
Platforms and runtime: Node.js >= 22.0.0 and npm >= 10.0.0. macOS: proven, on a patched host. Linux: proven on Ubuntu 24.04 (x86-64) only, on a patched host. Windows: roadmapped.
Install:   npx -y @sanctuary-framework/mcp-server protect --claude-code --no-open --no-dashboard
Verify:    npx -y @sanctuary-framework/mcp-server doctor --json
Uninstall: npx -y @sanctuary-framework/mcp-server uninstall
Evidence: every capability claim traces to a row in ASSURANCE_MATRIX.md, and a row reads proven only when a ca

What is proven, and what is not

Shortened. The full README is on GitHub.