---
name: avax-standards
description: Integrate token, vault, typed-authorization, ERC-8004 and x402 interfaces with Avalanche deployment checks.
---

# Standards, authorizations and agent payments

1. Select actual interface/implementation and verify [Addresses](../addresses/SKILL.md). ERC20 allowance, ERC721 ownership, ERC1155 per-ID balances and ERC4626 asset/share accounting differ. Check ERC165 where provided and actual receiver behavior; a symbol or interface claim is not behavior proof.
2. Use `examples/standards/erc4626.mjs` for bounded integer math. Paths/commands resolve from the executable bundle root. referenceConversion requires accountingModel:'proportional-no-fees' and accepts explicit virtual offsets (default zero). Choose offsets from the actual vault model instead of assuming those defaults apply. Conversion and deposit/redeem outputs round down; mint/withdraw required inputs round up. Read actual vault preview AND max methods for fee/liquidity behavior. Test adverse rounding and zero shares; the helper is not a universal vault model.
3. Use authorization.mjs to inspect USDC domain, authorizationState(authorizer,nonce), balance, pause and blacklist. The observed native-USDC domain is name 'USD Coin', version '2', chainId 43114 and its exact verifyingContract. Re-read instead of importing another chain's domain. newAuthorizationNonce creates fresh bytes32; never reuse fixtures.
4. Validate typed data against explicit authority: canonical TransferWithAuthorization/ReceiveWithAuthorization fields, chain/token/domain, from, permitted payee, integer budget, nonce and strict validity window at both chain and wall time. ReceiveWithAuthorization requires caller=payee. Helpers only prepare unsigned artifacts; later signatures grant transfer authority, not merely login.
5. Use erc8004.mjs to inspect Identity/Reputation code, linkage, version, ERC721 support and exact agent owner/URI/agentWallet. validateRegistration binds registry namespace/agentId and applies a strict endpoint import profile. Identity, reputation and x402Support do not prove competence, solvency or service availability. Do not contact/execute listed endpoints automatically.
6. Use x402.mjs after fixing HTTPS resource, payee, budget and timeout policy. Its bounded profile accepts canonical PAYMENT-REQUIRED base64 JSON, HTTP402, v2 exact, eip155:43114, native USDC and EIP3009 with verified domain. It rejects unsupported extensions, Permit2/7710/upto rather than guessing authority. Present exact unsigned payment scope before separately authorized signing/settlement.
7. Run `node --test examples/standards/standards.test.mjs` and `node research/parity-standards/capture-live.mjs`. Distinguish math/negative fixtures, live registry/domain reads and synthetic HTTP challenges. No real facilitator payment, NFT transfer, ERC1155 deployment or endpoint availability is claimed executed.

## Network feature and specification status

Read feature-policy.mjs and [Upgrades](../upgrades/SKILL.md) before EIP7702 delegation. ACP209 remains Proposed in reviewed sources; Fuji Helicon and Ethereum Pectra do not establish C-Chain activation. Delegation plans remain disabled until support is verified. An unavailable RPC method alone does not prove absence.

ERC8004 and ERC3009 have Draft EIP status in the reviewed sources despite deployed implementations. Separate specification, deployed version and facilitator support.

**Deliver:** standard/version/deployment; units/rounding; authority/domain/nonce policy; unsigned artifact; runtime/test evidence; unsupported paths.

Sources: [ERC4626](https://eips.ethereum.org/EIPS/eip-4626), [EIP712](https://eips.ethereum.org/EIPS/eip-712), [ERC3009](https://eips.ethereum.org/EIPS/eip-3009), [ERC8004](https://eips.ethereum.org/EIPS/eip-8004), [pinned ERC8004 deployment](https://github.com/erc-8004/erc-8004-contracts/tree/b9e466c250744a7e06b13dff9d3c2844ed64f825), [pinned x402 v2](https://github.com/x402-foundation/x402/tree/0c04a84eeceace349397274c5785c9ca7fcf9474), [network/facilitator support](https://docs.x402.org/core-concepts/network-and-token-support), [ACP209](https://build.avax.network/docs/acps/209-eip7702-style-account-abstraction).