Built for Synthesis · Ethereum · Base · Solana

The spending firewall for autonomous AI agents

Kartein is the programmable trust layer between AI agents and the Solana blockchain. Every payment is validated, every violation is blocked, every action is auditable.

8 policy checks·Multi-chain·Locus x402·Base + Solana

See it working

kartein.app/dashboard
Live

Total Spent

$47.50

/ $625 budget

Active Agents

3

connected

Transactions

42

last 24h

Approval Rate

85%

AgentAmountStatus
research-01$2.50Approved
trading-bot$450.00Blocked
data-miner$0.85Approved
research-01$1.20Approved
trading-bot$12.00Blocked
Try the live demo

Includes an agent terminal — type natural language commands and watch the policy engine respond.

How it works

Agents that pay

AI agents make autonomous payments via x402 on Base and Solana. Kartein validates every transaction against programmable policies before settlement via Locus.

Agents that trust

Trust is programmable. Per-agent spending limits, recipient whitelists, daily caps, and category restrictions define exactly what each agent can do.

Agents that cooperate

Multiple agents share a managed vault with individual budgets. One agent's limits don't affect another. Cooperative spending, individual accountability.

Agents that keep secrets

Agent wallet keys are isolated and never exposed. Policy rules act as access control — agents can only spend within their defined boundaries.

Five layers of protection

01

Vault

Secure USDC deposit pool with per-agent budget isolation. Funds remain locked until a policy-approved withdrawal clears.

02

Policy Engine

Programmable spending rules enforced on every transaction. Per-agent limits, recipient whitelists, time windows, and category controls.

03

x402 Proxy

Intercepts HTTP 402 payment requests before settlement. The gateway between agent intent and on-chain execution.

04

AI Monitor

Real-time anomaly detection on spending patterns. Flags unusual behavior and auto-escalates to human review.

05

Dashboard

Human oversight with kill switch and full audit trail. Freeze any agent instantly. Review every transaction.

Agents that pay. Under your control.

Deploy AI agents with programmable spending boundaries. Multi-chain policy engine. Solana devnet + Base mainnet via Locus.

Free · Open source · Solana devnet