Browser Test Client

Testnet-only browser client for inspecting Kaspa x402 offers, checking public-node connectivity, and rehearsing payment headers. The hosted gateway at demo.kaspa-x402.org runs the paid-canary-proven alpha.8 standard-native exact profile; see the gateway reference for deployed evidence.

Safety Boundary

The network is fixed to kaspa:testnet-10; there is no mainnet selector.
Generated or imported private keys stay in browser memory. The page does not write key material to local storage, cookies, query strings, or the server.
Reset clears the in-memory key, visible fields, and RPC connection state.
The only signed data that should leave the page is a transaction you intentionally broadcast through the public node network.
The apex domain hosts static files only. The hosted gateway and its paid test resources run on the separate demo.kaspa-x402.org subdomain.

Runtime Status

Endpoint override

Public HTTPS pages must use the listed wss:// endpoints. Local custom endpoints require a local preview opened with ?allow-custom-endpoints=1&endpoint=...; the field must match that local or private-network endpoint.

Not loaded.

{}

Testnet Key

Private key hex

Import only throwaway testnet keys. Do not import a key that controls mainnet funds; the same private key can derive addresses on multiple Kaspa networks.

Show private key Address

{}

x402 Offer Builder

Profile Amount (sompi) Timeout seconds Finality

Resource URL Resource description Pay-to address

PAYMENT-REQUIRED

{}

Exact Mock Flow

Use this to rehearse the 402 retry envelope against a mock or local gateway. The generated request authorization is a schema-only placeholder, not a valid signature. A real payer must derive and sign the canonical authorization digest, and a real gateway must independently verify and settle the transaction artifact.

Signed transaction artifact

Payment output index Observed transaction id

PAYMENT-SIGNATURE

{}

Offer Compatibility Debug

Paste a PaymentRequired JSON object to see which entries are supported by this Kaspa binding and which entries a client would skip during selection.

{}

Developer Notes

Run locally with npm run site:serve and open /demo/. The local preview binds to the LAN; use the host IP from another device. Add ?allow-custom-endpoints=1&endpoint=... only when testing a local or private-network node endpoint.
Fund generated addresses with testnet funds only. The Kaspa testnet page lists a TN10 faucet at faucet-tn10.kaspanet.io; a local or private faucet is also suitable.
The browser SDK is loaded from /vendor/kaspa-wasm/2.0.0/kaspa-core/. The browser uses public WSS endpoints directly; npm run check:pnn-browser verifies resolver lookup from Node. Runtime spike metadata is available at /demo/pnn-spike.json.
The published TypeScript helpers are currently Node-oriented for header encoding and hashing. This page uses browser-native header encoding until a browser-safe package build is added.
Public Node Network endpoints are shared test infrastructure. Treat outages, latency, and endpoint rotation as expected development failures.