Demo

Evidence

What 402 Sentry does, shown rather than described — the protocol exchange, the on-chain record, and the decision behind it.

Protocol Captured

Live x402 flow

The HTTP 402 challenge the seller actually returned, decoded — the terms the buyer had to meet before any value moved.

The seller was hosted locally at 127.0.0.1:8402 for this run. The network, asset, and settlement its challenge names are Base Sepolia.
Protocol
x402 v2
Scheme
exact
Network
eip155:84532 · Base Sepolia
Asset
USDC (Base Sepolia)
Amount
0.001 USDC · 1000 atomic
Resource
/testnet/paid/hello
Seller
hosted locally at 127.0.0.1:8402
On-chain Captured

Base Sepolia transaction proof

Seller-side output from the same request: the facilitator verified and settled the payment, and 402 Sentry recorded the Base Sepolia transaction that settlement produced.

The seller process ran locally; the settlement it reports happened on Base Sepolia.
Network
Base Sepolia · eip155:84532
Amount
0.001 USDC · 1000 atomic
Settlement
Proven
Facilitator
x402.org
Transaction
0xe168026eda07342dca7ab68c31c9e9e8f656c9f65bc0cc8ad8c9ae61fc08f6bf
On-chain Captured

BaseScan reference

The same transaction as an independent block explorer records it — the check that does not rely on anything 402 Sentry reports about itself.

BaseScan is an independent explorer and this page is not produced by 402 Sentry. The transfer was submitted by the facilitator, which is why the transaction sender and the payer are different addresses.
Status
Success
Network
Base Sepolia Testnet
Amount
0.001 USDC
Transaction hash
0xe168026eda07342dca7ab68c31c9e9e8f656c9f65bc0cc8ad8c9ae61fc08f6bf
Execution Captured

Buyer and seller execution

Both sides of the same exchange: what the buyer signed and sent, and what the seller returned once the facilitator had settled it.

Buyer side, run against the local seller under a testnet-only spend cap. The signing key stays in the runtime and is never committed.
Seller side of that same request, ending in the settlement it proved.
Buyer result
SETTLED
Seller result
SELLER_SETTLED
Facilitator
x402.org
Payer
0xE704…8139
Payee
0x5d5D…20aB
Product Captured

402 Sentry decision

The decision 402 Sentry recorded for that request, in the Live Trace view, with the trusted request facts held separate from the payment’s own claims.

Approved means no blocking policy violation was recorded against the amount, route, network, wallets, nonce, or metadata. A decision records the failures it produced, not proof that every control ran.
Decision
Approved
Run context
Base Sepolia · testnet
HTTP
200
Amount
0.001 USDC
Resource
/testnet/paid/hello
Product Captured

Dashboard and event stream

The operator view for the same run: what was decided, and what it added up to.

Counts are for the Base Sepolia run context only.
Recorded decisions
1
Approved
1
Blocked
0
Errors
0
Run context
Base Sepolia
Protection Captured

Blocked control examples

Two refusals recorded in the local mock runtime, where no value moves: a payment proof presented against a host outside the allow-list, and payment metadata carrying a secret-shaped value. The amounts, networks and wallets inside these captures are the payment’s own unverified claims — nothing here settled, and nothing here happened on Base Sepolia.

Local mock runtime. The proof was aimed at a host the seller does not charge for, which is what redirecting a valid payment to an attacker-controlled domain looks like.
Local mock runtime. The metadata scan found an api_key-shaped value and the request was refused before anything was forwarded or stored.
Runtime
Local mock runtime · no value moved
Domain example
DOMAIN_NOT_ALLOWED · REQUEST_BINDING_MISMATCH
Metadata example
METADATA_LEAK_DETECTED
Response
HTTP 402 · payment refused