Spec Compliance Skill

Verify smart contract implementations comply with EIP/ERC standards and protocol specifications. Non-compliant implementations cause integration failures, fund losses, and security vulnerabilities.

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Why Compliance Matters

Impact of Non-Compliance	Example
Integration failure	DEXs can't list non-standard ERC20 (missing decimals())
Silent fund loss	ERC721 safeTransferFrom not calling onERC721Received = NFTs lost
Security vulnerability	EIP-712 without chainId = cross-chain signature replay
Accounting errors	ERC4626 wrong rounding direction = vault inflation attack
Ecosystem rejection	Bridges, wallets, indexers refuse non-standard tokens

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Supported Standards

Token Standards

Standard	Type	Key Functions	Common Issues
ERC-20	Fungible token	transfer, approve, transferFrom	Missing return values, approve race
ERC-721	Non-fungible token	safeTransferFrom, approve, ownerOf	Missing receiver callback
ERC-1155	Multi-token	safeTransferFrom, safeBatchTransferFrom	Batch operation atomicity
ERC-4626	Tokenized vault	deposit, withdraw, convertToShares	Rounding direction, first depositor attack
ERC-2612	Permit (gasless approve)	permit, nonces, DOMAIN_SEPARATOR	Signature replay, frontrunning

Infrastructure Standards

Standard	Type	Security Focus
EIP-712	Typed data signing	Domain separator, chain ID
EIP-1967	Proxy storage slots	Standard slot locations
EIP-2535	Diamond standard	Selector collision, storage isolation
EIP-4337	Account abstraction	UserOp validation, paymaster trust
EIP-1153	Transient storage	TSTORE/TLOAD lifecycle
EIP-2981	Royalty info	Not enforceable (informational only)

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Compliance Verification Approach

1. Interface Completeness

Does the contract implement ALL required functions with correct signatures?

// ERC-20 REQUIRED interface (IERC20)
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
function transfer(address to, uint256 amount) external returns (bool);
function allowance(address owner, address spender) external view returns (uint256);
function approve(address spender, uint256 amount) external returns (bool);
function transferFrom(address from, address to, uint256 amount) external returns (bool);

// ERC-20 REQUIRED events
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);

// OPTIONAL but expected by most integrations
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);

2. Behavioral Compliance

Does each function behave as specified? (Not just exist with the right signature)

3. Edge Case Handling

Does the implementation handle boundary conditions specified in the standard?

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Resources

• ERC Standards
• EIP Security

Workflows

• Compliance Audit