Tessera Guard
PX-04
North Star
Five stages, and not one of them is a cloud.
Discover, watch, detect, explain, act — all of it on the machine you are sitting at, over a store that is a file on your own disk. Pull the network cable and every box in the chain still runs.
Five stages, left to right, all of them on your own machine. Nothing in this chain has a cloud step in it — pull the internet cable and every box still runs.
01
Discover
ARP · ICMP · mDNS · HTTP banner
Four sweeps run together, then each device is named from its OUI vendor, its open ports and the services it advertises.
02
Watch
Interface counters · connections · processes
Traffic and per-process behaviour are sampled continuously from OS counters, which is why it costs almost nothing to leave on.
03
Detect
10 behavioural engines · 15 vulnerability rules
Findings come from how something behaves over time, not from a signature list, and each keeps the numbers that fired it.
04
Explain
Plain English · MITRE ATT&CK · tagged steps
Every finding states its evidence and its fix, with each remediation step marked safe, caution or destructive.
05
Act
Quarantine · terminate · report
Move a finding from Active to Investigating to Mitigated, quarantine the device, and export the period as a report.
AI control
29 tools over the Model Context Protocol, on a loopback-only endpoint behind a bearer token, so Claude or Cursor can drive the app. Anything that mutates — kill a process, start a capture, quarantine a device — is gated twice: an in-app approval dialog and the operating system's own administrator prompt.
On the device
One SQLite store on your own disk. No account, no telemetry, no cloud analysis, nothing uploaded — the whole product is the opposite of an agent reporting to a SaaS.
What local-first actually buys you
No account to breach
There is no sign-up, no tenant and no server holding a copy of your network. The attack surface of the product is the machine it runs on.
Usable where SaaS is not
A lawyer, a clinician or a journalist cannot send traffic metadata to a vendor. That is not a preference; it is often the rule they work under.
Quiet enough to leave on
Traffic comes from OS interface counters rather than a permanent capture, which is where under 20% CPU and roughly 200 MB comes from.
An AI can drive it safely
The MCP endpoint binds to loopback and rejects non-loopback origins, and anything that mutates needs both an in-app approval and the operating system's own administrator prompt.
The specification.
Platforms
macOS · Windows
Detection
Behavioural · MITRE ATT&CK mapped
Network
Device discovery · live traffic · packet capture
Malware
Indicators-of-compromise scan · quarantine vault
VPN
WireGuard · stealth mode over WebSocket/TLS