Security

Agents operate with wallets. Clanker Banker is designed so a single bad loop cannot silently “subscribe forever” — every paid call is an explicit x402 settle.

Spend caps (agent wallet protection)

Clanker Banker prices are fixed per tool. Cap spending in the client before signing payment:

// install/client.mjs pattern
const MAX_USD = 0.05; // hard cap per call
// if 402 amountUsdApprox > MAX_USD → abort, do not sign

Optional request header (documented for SDKs):

X-Clanker-Max-Usd: 0.01

If present and the tool list price exceeds the cap, Clanker Banker returns 402 with code: SPEND_CAP and does not expect payment. See free price list: /v1/prices.

Network isolation

Only http: / https: public hosts
Blocks localhost, RFC1918, link-local, cloud metadata hostnames
Paid tools require valid URL validation before charge

Payment security

Exact-amount x402 on Base USDC — no open “charge whatever”
Settlement via facilitator (CDP when configured)
Operators never receive agent private keys

Production recommendations

Use a dedicated agent wallet with limited USDC balance
Set client max USD per call and daily budget
Prefer noCache: true for sensitive URLs
Move off *.workers.dev to a custom domain you control
Monitor /dashboard for unexpected 402 storms