Axon Smart Contracts

Non-custodial vault contracts for autonomous AI agents. Built with Foundry.

Overview

Axon lets bot operators deploy per-owner vaults, register bot public keys, define spending policies, and let their bots make gasless payments via EIP-712 signed intents — without bots ever touching private keys or gas.

Contracts

Contract	Description
AxonVault	Per-owner treasury vault. Holds funds, enforces bot auth and spending caps, verifies EIP-712 signed intents.
AxonVaultFactory	Deploys vault clones via EIP-1167 minimal proxies with CREATE2 deterministic addresses.
AxonRegistry	Protocol-wide configuration: authorized executors, approved swap routers, TWAP oracle config, default tokens.

Key Features

• Three intent types: executePayment (direct + swap), executeProtocol (DeFi interactions with optional ETH), executeSwap (in-vault rebalancing)
• EIP-712 signatures: Bots sign typed intents off-chain, never submit transactions
• Operator role: Delegated hot wallet that can tighten policies (add bots, lower limits, pause) but never loosen them
• Spending limits: Per-bot, multi-window (1h/3h/24h/7d/30d), with configurable AI verification thresholds
• Destination controls: Global + per-bot whitelist, global blacklist (blacklist always wins)
• TWAP oracle: USD-denominated maxPerTxAmount enforcement for non-stablecoin tokens
• ERC-1271: Vault validates owner and bot signatures for off-chain protocols (Seaport, CoWSwap, Permit2)
• 2-step ownership: Ownable2Step transfer with renounce blocked

Development

# Install dependencies
forge install

# Build
forge build

# Run tests (323 unit tests)
forge test

# Run tests with gas report
forge test --gas-report

# Format
forge fmt

Testing

Unit tests cover all contract functions, access control, and edge cases:

forge test -vvv

Property-based fuzz testing with Medusa (88 invariant properties):

medusa fuzz

The fuzz harness at test/fuzz/AxonVaultFuzzHarness.sol covers: balance conservation, payment/swap/protocol execution, operator ceiling enforcement, bot lifecycle, whitelist/blacklist integrity, signature validation, ERC-1271, and more.

Deployed Contracts

Mainnet (Arbitrum One + Base)

Deterministic CREATE2 — same addresses on both chains.

Contract	Address	Arbiscan	BaseScan
AxonRegistry	0xbc1b61653EDB3906310D4AC8a789E144B1C5A0Ff	View	View
AxonVaultFactory	0x271cf17A42435Dc08f320c85834C08a3cb71A10d	View	View
Vault Implementation	0x236ea8301d2fC3e177e2C198E67CAFcECE6e1ed0	View	View

Testnets (Base Sepolia + Arbitrum Sepolia)

Deterministic CREATE2 — same addresses on both testnets.

Contract	Address
AxonRegistry	0xf47E517B78FA7a1045E9857CD39cDC024a1a59b4
AxonVaultFactory	0x2df2982445bd4dc38d496cec621c9b514b469792
Vault Implementation	0x9c427EbEBE9Acd98ac49e166E3AB159a7e1648F5

Architecture

Owner deploys vault via Factory (CREATE2)
  └─ Vault holds ERC-20 tokens + native ETH
      ├─ Owner: full control (withdraw, configure, pause)
      ├─ Operator: tighten-only (add bots within ceilings, lower limits, pause)
      └─ Bots: sign EIP-712 intents (PaymentIntent, ExecuteIntent, SwapIntent)
          └─ Authorized executor calls vault with bot's signature
              └─ Vault verifies: bot active + sig valid + deadline OK + caps enforced

Security Model

Actor	Controls	Risk if Compromised
Owner (HW wallet / multisig)	Full vault control, bot whitelist, withdrawal	Catastrophic but hardened
Operator (hot wallet)	Add bots within ceilings, tighten limits, pause	Limited by ceilings
Bot key	Signs payment intents only	Bounded by per-tx caps + spending limits

License

MIT

Links

• Website
• Dashboard
• npm — @axonfi/sdk
• PyPI — axonfi
• Twitter/X — @axonfixyz