Enforcement modes

Untch offers a ladder of enforcement. Start soft for adoption. Tighten when you need physics.

Mode A: Advisory ASP

The agent (or its framework) calls Untch tools before paying:

• create_spend_intent
• preflight_payment

Software honesty only: if the agent skips preflight, Untch cannot stop the chain transaction. Use Mode B or C when you need stronger guarantees.

Status: Live on asp.untch.xyz.

Mode B: Untch Guard

Open-source middleware for x402 / APP-style flows:

npm install @untch/x402-guard

On a 402 challenge the guard:

1. Runs Challenge Binding Check (exact field match after normalization)
2. Calls preflight
3. Only then allows your signer to pay

The guard never holds private keys. You pass a signAndPay function.

Status: Live package. See Untch Guard.

Mode C: Untch Vault

Funds live in an on-chain UntchVault. Spend requires an oracle EIP-712 signature within caps. Owner withdraw is always available without Untch.

ASP path: on APPROVED preflight, pass vaultAddress when ORACLE_PRIVATE_KEY is configured to receive sig.

Status: Contracts deployed. Continuous multi-tenant oracle map is operational configuration. Demo vault exists on testnet only.

Mode D: Broker Guard

Broker-side gate for APP flows: hold challenge state, verify credentials against the original request, forward only after policy pass.

Status: Roadmap. Not a live product path. Do not claim Mode D in production pitches until it ships.

Choosing a mode

Need	Mode
Fast integration, soft control	A
Stop bad 402 challenges before sign	B
Hard on-chain caps	C
APP broker integration	D (future)

Related

• Quickstart
• Vault