Hardware Security Key for AI Agents
Protect your AI credentials with tamper-resistant silicon
NexusClaw is the first hardware security key designed specifically for AI agents. Built on the Agent Vault Protocol (AVP), it provides:
- Hardware-backed credential storage — API keys, tokens, and secrets stored in tamper-resistant silicon
- Cryptographic operations — Sign, verify, and attest without exposing private keys
- Plug-and-play USB — Works with any system via USB CDC serial interface
- Open source firmware — Fully auditable, community-driven development
AI agents need API keys and credentials to operate. Today, these are typically stored in:
- Environment variables (leaked via logs, env dumps)
- Config files (committed to git, backed up insecurely)
- Secret managers (still software-based, single point of failure)
A compromised credential gives attackers unlimited access to your AI services, billing, and data.
NexusClaw stores your credentials in a TROPIC01 secure element — the same class of hardware used in banking cards and hardware wallets. Keys are:
- Generated inside the chip using true random number generators
- Stored in tamper-resistant memory with active shields
- Never exported — cryptographic operations happen on-chip
- Protected by PIN with lockout after failed attempts
┌─────────────────────────────────────────────────────────────────┐
│ NexusClaw USB Key │
│ ┌─────────────────────────────────────────────────────────────┐│
│ │ STM32U535 MCU ││
│ │ - USB CDC interface ││
│ │ - AVP protocol processor ││
│ │ - TrustZone isolation ││
│ └──────────────────────────┬──────────────────────────────────┘│
│ │ SPI (encrypted session) │
│ ┌──────────────────────────▼──────────────────────────────────┐│
│ │ TROPIC01 Secure Element ││
│ │ - 128 secure storage slots ││
│ │ - ECC, AES-256-GCM, SHA-3 ││
│ │ - Tamper detection ││
│ │ - True random number generator ││
│ └─────────────────────────────────────────────────────────────┘│
└─────────────────────────────────────────────────────────────────┘
| Feature | Description |
|---|---|
| TROPIC01 Secure Element | Tamper-resistant chip from Tropic Square |
| 128 Storage Slots | Store up to 128 secrets (256 bytes each) |
| ECC P-256 & Ed25519 | Hardware-based signing and verification |
| AES-256-GCM | Authenticated encryption for data protection |
| PIN Protection | 6-digit PIN with exponential backoff |
| Attestation | Verify device authenticity before trusting it |
| Integration | Status |
|---|---|
| AVP Python Client | ✅ Ready |
| AVP TypeScript Client | ✅ Ready |
| LangChain | ✅ Ready |
| CrewAI | ✅ Ready |
| ZeroClaw | ✅ Ready |
| Claude MCP | ✅ Ready |
| Custom Agents | ✅ Any AVP client |
Plug NexusClaw into any USB port. It appears as a serial device:
- Linux:
/dev/ttyACM0 - macOS:
/dev/tty.usbmodem* - Windows:
COM3(or similar)
# Python
pip install avp-py
# Node.js
npm install @avp-protocol/avp-ts
# Rust
cargo add avp-rsfrom avp import Vault
# Connect to NexusClaw
vault = Vault("avp+usb:///dev/ttyACM0")
# Authenticate with PIN
vault.authenticate(pin="123456")
# Store your API key
vault.store("anthropic_api_key", "sk-ant-...")
# Later: retrieve it
api_key = vault.retrieve("anthropic_api_key")from langchain_anthropic import ChatAnthropic
from avp import Vault
vault = Vault("avp+usb:///dev/ttyACM0")
vault.authenticate(pin="123456")
# API key from hardware - never on disk
llm = ChatAnthropic(api_key=vault.retrieve("anthropic_api_key"))
response = llm.invoke("Hello from hardware-secured AI!")NexusClaw implements the full Agent Vault Protocol:
| Operation | Description |
|---|---|
DISCOVER |
Query device capabilities |
AUTHENTICATE |
Start secure session with PIN |
STORE |
Store a secret |
RETRIEVE |
Retrieve a secret |
DELETE |
Delete a secret |
LIST |
List stored secret names |
ROTATE |
Rotate a secret value |
| Operation | Description |
|---|---|
HW_CHALLENGE |
Verify device authenticity |
HW_SIGN |
Sign data with hardware key (key never exported) |
HW_ATTEST |
Get signed attestation of device state |
| Spec | Value |
|---|---|
| Connector | USB Type-A |
| Dimensions | 45mm × 18mm × 8mm |
| Weight | 8g |
| Operating Temp | -20°C to +70°C |
| Storage Temp | -40°C to +85°C |
| Spec | Value |
|---|---|
| Supply Voltage | 5V USB |
| Current (idle) | < 10mA |
| Current (active) | < 50mA |
| Spec | Value |
|---|---|
| Secure Element | TROPIC01 |
| Certifications | CC EAL5+ (pending) |
| Random Source | TRNG + PUF |
| Tamper Protection | Active mesh, sensors |
This repository contains the open-source firmware for NexusClaw. It is based on:
- MCU: STM32U535 (Cortex-M33, TrustZone)
- Secure Element: TROPIC01 via SPI
- USB: CDC ACM (serial) interface
- Protocol: AVP over JSON
# Prerequisites
apt install gcc-arm-none-eabi dfu-util
# Clone with submodules
git clone --recursive https://github.com/avp-protocol/nexusclaw.git
cd nexusclaw
# Build
cd app
make clean
make- Hold button while connecting USB (enters DFU mode)
- Flash with dfu-util:
dfu-util -a 0 -s 0x08000000:leave -D build/app.bin┌─────────────────────────────────────────────────────────────────┐
│ UNTRUSTED │
│ Host OS, Network, Filesystem, Other Applications │
└───────────────────────────────┬─────────────────────────────────┘
│ USB (AVP JSON commands)
┌───────────────────────────────▼─────────────────────────────────┐
│ PARTIALLY TRUSTED │
│ STM32U535 MCU │
│ - Validates AVP commands │
│ - Never sees plaintext keys │
│ - Session tokens are ephemeral │
│ - TrustZone isolates AVP code │
└───────────────────────────────┬─────────────────────────────────┘
│ SPI (encrypted L2 session)
┌───────────────────────────────▼─────────────────────────────────┐
│ FULLY TRUSTED │
│ TROPIC01 Secure Element │
│ - Keys generated internally (never imported) │
│ - Keys stored in tamper-resistant memory │
│ - Crypto operations performed on-chip │
│ - Keys NEVER exported in plaintext │
│ - Tamper detection → automatic key zeroization │
└─────────────────────────────────────────────────────────────────┘
| Feature | Env Vars | Secret Manager | HSM | NexusClaw |
|---|---|---|---|---|
| Cost | Free | $$ | $$$$ | $ |
| Hardware Security | ❌ | ❌ | ✅ | ✅ |
| Portable | ❌ | ❌ | ❌ | ✅ |
| Open Source | N/A | ❌ | ❌ | ✅ |
| AI Agent Focused | ❌ | ❌ | ❌ | ✅ |
| Plug-and-Play | ❌ | ❌ | ❌ | ✅ |
- Fork TROPIC01 USB devkit firmware
- Add AVP protocol layer
- Production PCB design
- Injection molded enclosure
- FCC/CE certification
- CC EAL5+ certification
- Volume manufacturing
- Launch March 2026
NexusClaw is launching soon. Join the waitlist:
- AVP Specification — The protocol standard
- AVP-Tropic — Evaluation firmware for Secure Tropic Click
- avp-py — Python client
- avp-ts — TypeScript client
- avp-rs — Rust client
This project is licensed under the Apache License 2.0 - see LICENSE.txt for details.
The TROPIC01 secure element is an open hardware design from Tropic Square.
NexusClaw — Hardware Security for the AI Age
Part of the Agent Vault Protocol ecosystem