Skip to main content

Documentation Index

Fetch the complete documentation index at: https://docs.algovoi.co.uk/llms.txt

Use this file to discover all available pages before exploring further.

The AlgoVoi Chrome extension is the in-house browser wallet for the AlgoVoi payment stack. As of v2.5.0 (2026-05-19) it ships native x402 / MPP / AP2 support across six mainnet chains in a single extension: Algorand, VOI, Hedera, Base, Arc, and Tempo. Eighteen of eighteen protocol × chain combinations are wired in one popup, with chain-appropriate signing schemes routed transparently behind the UI. Install from the Chrome Web Store or build from source at chopmob-cloud/AlgoVoi.

​
Why the extension exists

Most browser wallets pick one chain family (EVM, Solana, or AVM) and run with it. Agent payments cross those boundaries constantly: a buyer agent on Base settling an x402 charge for an Algorand merchant, or an MPP gateway issuing both method="evm" and method="avm" challenges for the same resource. Routing that through three separate wallets multiplies key custody, breaks the approval flow, and defeats the point of native browser-handled fetch() interception. The AlgoVoi extension collapses the six chains AlgoVoi-the-platform settles on into a single browser wallet, with one popup, one approval UX, and a single page-injected window.algorand provider that resolves the right signing path automatically.

​
Chain × protocol coverage matrix

ProtocolAlgorandVOIHederaBaseArcTempo
x402✅✅✅✅✅✅
MPP✅✅✅✅✅✅
AP2✅✅✅✅✅✅
All eighteen combinations wired from v2.5.0. The extension auto-detects the active chain at the page, account, or challenge level and routes the signing call through the correct chain client without user intervention.

​
Signing scheme by chain

Chainx402 / MPP signingAP2 mandate signing
Algorandalgosdk txn (Ed25519) — native ALGO or USDC ASA 31566704algosdk.signBytes (Ed25519)
VOIalgosdk txn (Ed25519) — native VOI or aUSDC ASA 302190algosdk.signBytes (Ed25519)
HederaHashPack WalletConnect (HTS) — HBAR or USDC HTS 0.0.456858algosdk.signBytes (Ed25519, reuses the AVM key)
Baseviem signTransaction (secp256k1) + ERC-20 transfer(USDC) on 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913viem signMessage (EIP-191 personal_sign), 65-byte signature base64url-encoded
Arcviem signTransaction (secp256k1) + native value transfer (Arc’s native gas token is USDC)viem signMessage (EIP-191)
Tempoviem signTransaction (secp256k1) + ERC-20 transfer(USDCe)viem signMessage (EIP-191)
The AVM seed (Algorand + VOI + Hedera) and the EVM seed (Base + Arc + Tempo) live as separate keys inside the same encrypted vault. The vault holds both pairs, and the active-account selector in the popup decides which key path the next signing request will take.

​
Key features

  • Encrypted vault — PBKDF2 (600k iterations) + AES-GCM-256. Keys never leave the device unencrypted; the session key is held in service-worker memory only and wiped on lock or service-worker suspension.
  • 30-day local signing key — Import a 25-word mnemonic with a 30-day TTL for reliable local signing without WalletConnect-relay dependency. Stricter than MetaMask or Phantom defaults; auto-wipes after the TTL expires.
  • Falcon PQC signatures — Post-quantum Falcon-1024 accounts on Algorand mainnet, WASM build (88 KB) of the same C Falcon library backing the AVM v12 falcon_verify opcode. Quantum-resistant signing today.
  • AI agent wallet — WalletConnect Web3Wallet mode lets AI agents pair with the extension and request transaction signing without ever touching private keys. All six chains addressable in a single WC session via CAIP-2 namespaces.
  • Anti-phishing — Clipboard hijacking detection (warns if the pasted address differs from the copied one), homograph domain detection (flags Unicode lookalike domains), AVM transaction simulation via algod /v2/transactions/simulate, dangerous-field warnings on rekey / clawback / closeRemainderTo.
  • Spending cap vault — Deploy an AVM smart contract enforcing per-transaction and daily caps for autonomous agent payments. Owner actions (suspend, resume, withdraw, update limits) via mnemonic or WalletConnect.
  • DEX swaps — Algorand ASAs via Haystack Router (Tinyman / Pact / Folks aggregation); VOI tokens via Snowball direct pool swaps with slippage protection.
  • Allbridge USDC bridge — Bridge USDC from Algorand to thirteen destination chains via the Bridge tab; transactions built server-side (MCP) and signed locally, with txId-trackable transfer status.
  • Coinbase Onramp — Buy ALGO directly from the wallet via a one-time session-token flow; wallet addresses never appear in URL parameters.
  • Auto-update notifications — Daily check against the MCP /version endpoint; amber badge + banner when a newer release is available.
See the extension repository README for the full hardening list (Tier I-XXIV) and the latest security audit report.

​
Page integration (window.algorand)

The extension injects a window.algorand provider into every page, compatible with ARC-0027: 
// Connect and get accounts
const { accounts } = await window.algorand.enable({ genesisID: "mainnet-v1.0" });

// Sign AVM transactions
const signedTxns = await window.algorand.signTransactions([txnBase64]);

// Sign arbitrary bytes (AP2 mandate hashes, AVM-side)
const { sig } = await window.algorand.signBytes({ data: new Uint8Array([...]) });
For EVM chains the page receives the standard EIP-1193 provider via WalletConnect pairing (the extension acts as the WC wallet for eip155:8453, eip155:5042002, eip155:1329). AP2 mandate requests across all six chains flow through window.algorand.ap2.requestPayment(cartMandate); the extension routes the underlying signature call to the correct chain client based on the active account.

​
Automatic 402 handling

The extension intercepts fetch() and XMLHttpRequest calls that return HTTP 402 with PAYMENT-REQUIRED (x402 v1) or WWW-Authenticate: Payment (MPP) headers, surfaces an approval popup with the transaction details, signs locally with the active-account key, broadcasts the on-chain transaction (AVM via algosdk, HTS via HashPack WC, or EVM via viem + eth_sendRawTransaction), and retries the original request with the resulting PAYMENT-SIGNATURE or Authorization: Payment header. No page-side payment code is needed. 
// This fetch triggers an approval popup if the server returns 402.
// The extension picks the chain from the challenge's accepts[] legs and the active account.
const response = await fetch("https://api.example.com/premium-data");
const data = await response.json(); // resolves after payment is approved
MPP credentials on EVM chains carry a did:pkh:eip155:<chainId>:<address> source field so downstream verifiers resolve the signer to the correct chain without a translation layer; AVM credentials carry the standard algorand:<genesis_id> or equivalent CAIP-2 identifier.

​
Build and load (development)

git clone https://github.com/chopmob-cloud/AlgoVoi.git
cd AlgoVoi
npm install
cp .env.example .env
# Fill in VITE_WC_PROJECT_ID, VITE_HAYSTACK_ROUTER_API_KEY (optional)
npm run build
Load dist/ as an unpacked extension in Chrome (chrome://extensions, Developer mode → Load unpacked) or dist-firefox/manifest.json as a temporary add-on in Firefox (about:debugging#/runtime/this-firefox).

​
See also

  • x402 protocol — content paywall / API metering payment protocol
  • MPP protocol — Machine Payments Protocol with WWW-Authenticate: Payment semantics
  • AP2 protocol — Google Agent Payments Protocol mandate signing
  • Concept: chains overview — full chain support matrix across the platform
  • MCP server — programmatic access to the same payment surface from Claude, Cursor, and Windsurf