Structured interface entries describe functions, events and errors.
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A machine-readable form catalog lists each action and the types of its fields.
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Build a transfer call from typed fieldsStep 1 / 4
The standard transfer interface takes an address and a raw integer amount. This diagram uses address one and amount one hundred.
The standard transfer interface takes an address and a raw integer amount. This diagram uses address one and amount one hundred.Keccak-256 of the canonical signature supplies the first four bytes. The transfer selector is a9059cbb.An address is twenty bytes. Standard ABI encoding adds twelve zero bytes on the left to fill one thirty-two-byte word.The integer one hundred is hex 64, left-padded in word one. Selector plus two words produces sixty-eight bytes of standard calldata.
Animated local teaching model. No wallet, RPC or live blockchain data. Some labels and hashes are abbreviated for readability.
Entries have kinds
An ABI can include function, event, error, constructor and other relevant entry types. A function entry provides its name, inputs, outputs and state mutability metadata.
Tuple components need structure
A tuple type uses component definitions to describe its members. Nested arrays of tuples retain the relevant array dimensions alongside that component schema.
Internal names are not all wire types
Compiler metadata such as internalType can preserve source-level information. The external encoding still follows the canonical ABI type rules.
The JSON is not deployment proof
Anyone can provide an interface file. Match it with the intended address, implementation and network when making claims about real execution. The local lab also accepts concise human-readable declarations.