ERC Standards¶

abi-to-mcp automatically detects common ERC token standards based on function signatures.

Detection Logic¶

Standards are detected by checking for required function signatures:

graph TD
    A[Parse ABI] --> B{Has ERC20 functions?}
    B -->|Yes| C[ERC20]
    B -->|No| D{Has ERC721 functions?}
    D -->|Yes| E[ERC721]
    D -->|No| F{Has ERC1155 functions?}
    F -->|Yes| G[ERC1155]
    F -->|No| H[Unknown]

ERC20: Fungible Tokens¶

The most common token standard for fungible tokens like USDC, DAI, LINK.

Required Functions¶

Function	Signature	State
`name`	`name() → string`	view
`symbol`	`symbol() → string`	view
`decimals`	`decimals() → uint8`	view
`totalSupply`	`totalSupply() → uint256`	view
`balanceOf`	`balanceOf(address) → uint256`	view
`transfer`	`transfer(address,uint256) → bool`	nonpayable
`transferFrom`	`transferFrom(address,address,uint256) → bool`	nonpayable
`approve`	`approve(address,uint256) → bool`	nonpayable
`allowance`	`allowance(address,address) → uint256`	view

Required Events¶

Event	Signature
`Transfer`	`Transfer(address indexed, address indexed, uint256)`
`Approval`	`Approval(address indexed, address indexed, uint256)`

Common Extensions¶

Extension	Functions
ERC20Permit	`permit`, `nonces`, `DOMAIN_SEPARATOR`
ERC20Burnable	`burn`, `burnFrom`
ERC20Mintable	`mint`
ERC20Pausable	`pause`, `unpause`, `paused`

Example Detection¶

from abi_to_mcp.parser import ABIParser

parser = ABIParser()
parsed = parser.parse(usdc_abi)

assert parsed.detected_standard == "ERC20"

ERC721: Non-Fungible Tokens¶

The standard for unique tokens like NFTs (BAYC, CryptoPunks, etc.).

Required Functions¶

Function	Signature	State
`balanceOf`	`balanceOf(address) → uint256`	view
`ownerOf`	`ownerOf(uint256) → address`	view
`safeTransferFrom`	`safeTransferFrom(address,address,uint256)`	nonpayable
`safeTransferFrom`	`safeTransferFrom(address,address,uint256,bytes)`	nonpayable
`transferFrom`	`transferFrom(address,address,uint256)`	nonpayable
`approve`	`approve(address,uint256)`	nonpayable
`setApprovalForAll`	`setApprovalForAll(address,bool)`	nonpayable
`getApproved`	`getApproved(uint256) → address`	view
`isApprovedForAll`	`isApprovedForAll(address,address) → bool`	view

Required Events¶

Event	Signature
`Transfer`	`Transfer(address indexed, address indexed, uint256 indexed)`
`Approval`	`Approval(address indexed, address indexed, uint256 indexed)`
`ApprovalForAll`	`ApprovalForAll(address indexed, address indexed, bool)`

Common Extensions¶

Extension	Functions
ERC721Metadata	`name`, `symbol`, `tokenURI`
ERC721Enumerable	`totalSupply`, `tokenOfOwnerByIndex`, `tokenByIndex`
ERC721Burnable	`burn`
ERC721Royalty	`royaltyInfo` (ERC2981)

Detection Priority¶

ERC721 detection requires ownerOf (unique to NFTs) to distinguish from ERC20.

ERC1155: Multi-Token¶

Supports both fungible and non-fungible tokens in a single contract.

Required Functions¶

Function	Signature	State
`balanceOf`	`balanceOf(address,uint256) → uint256`	view
`balanceOfBatch`	`balanceOfBatch(address[],uint256[]) → uint256[]`	view
`setApprovalForAll`	`setApprovalForAll(address,bool)`	nonpayable
`isApprovedForAll`	`isApprovedForAll(address,address) → bool`	view
`safeTransferFrom`	`safeTransferFrom(address,address,uint256,uint256,bytes)`	nonpayable
`safeBatchTransferFrom`	`safeBatchTransferFrom(address,address,uint256[],uint256[],bytes)`	nonpayable

Required Events¶

Event	Signature
`TransferSingle`	`TransferSingle(address indexed, address indexed, address indexed, uint256, uint256)`
`TransferBatch`	`TransferBatch(address indexed, address indexed, address indexed, uint256[], uint256[])`
`ApprovalForAll`	`ApprovalForAll(address indexed, address indexed, bool)`
`URI`	`URI(string, uint256 indexed)`

Common Extensions¶

Extension	Functions
ERC1155MetadataURI	`uri`
ERC1155Supply	`totalSupply`, `exists`
ERC1155Burnable	`burn`, `burnBatch`

Detection Priority¶

ERC1155 is detected by balanceOfBatch (unique signature with two arrays).

Other Standards¶

ERC4626: Tokenized Vaults¶

Yield-bearing vaults (like Yearn or Aave).

Function	Signature
`asset`	`asset() → address`
`deposit`	`deposit(uint256,address) → uint256`
`withdraw`	`withdraw(uint256,address,address) → uint256`
`convertToShares`	`convertToShares(uint256) → uint256`
`convertToAssets`	`convertToAssets(uint256) → uint256`

ERC2612: Permit¶

Gasless approvals for ERC20 tokens.

Function	Signature
`permit`	`permit(address,address,uint256,uint256,uint8,bytes32,bytes32)`
`nonces`	`nonces(address) → uint256`
`DOMAIN_SEPARATOR`	`DOMAIN_SEPARATOR() → bytes32`

ERC2981: NFT Royalty¶

Royalty information for NFT marketplaces.

Function	Signature
`royaltyInfo`	`royaltyInfo(uint256,uint256) → (address,uint256)`

Detection in Practice¶

Using in Code¶

from abi_to_mcp.parser import ABIParser

parser = ABIParser()
parsed = parser.parse(abi)

if parsed.detected_standard == "ERC20":
    print("This is a fungible token")
elif parsed.detected_standard == "ERC721":
    print("This is an NFT collection")
elif parsed.detected_standard == "ERC1155":
    print("This is a multi-token contract")
else:
    print("Unknown or custom contract")

CLI Output¶

$ abi-to-mcp inspect 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48

📋 Contract Analysis
═══════════════════════════════════════════════════════════════

📊 Detected Standard: ERC20
   ✓ name
   ✓ symbol
   ✓ decimals
   ✓ totalSupply
   ✓ balanceOf
   ✓ transfer
   ✓ approve
   ✓ transferFrom
   ✓ allowance

Standard Comparison¶

Feature	ERC20	ERC721	ERC1155
Fungible	✓	✗	✓
Non-Fungible	✗	✓	✓
Multiple IDs	✗	✓	✓
Batch Transfer	✗	✗	✓
Token URI	✗	✓	✓
Decimals	✓	✗	✗

Adding Custom Standards¶

Extend the parser to detect custom standards:

from abi_to_mcp.parser import ABIParser

class CustomParser(ABIParser):
    def detect_standard(self, functions, events):
        # Check for custom standard
        func_names = {f.name for f in functions}

        if "myCustomFunction" in func_names:
            return "MyCustomStandard"

        # Fall back to default detection
        return super().detect_standard(functions, events)