@txkit/tx-decoder

@txkit/tx-decoder

Decode raw EVM calldata into structured DecodedCall trees compatible with @txkit/tx-protocol clearSigning fields.

v0.1.0-alpha - shape and surface may shift before v1.0.

What it does

Takes an EvmCall ({to, data, value}) plus a chain ID, returns a DecodedCall with:

• function selector (first 4 bytes)
• resolved function name
• decoded arguments typed against an ABI
• optional ERC-7730 clearSigning rules

Lookup order:

• inline abi option (highest priority)
• registry entry for (chain, to) (loaded JSON descriptors)
• async fourByte resolver fallback
• unknown - selector only, no args

Install

npm install @txkit/tx-decoder@alpha @txkit/tx-protocol@alpha viem

Usage

import { decodeCall, buildRegistry } from '@txkit/tx-decoder'

const result = await decodeCall(
  {
    call: { to: '0x...', data: '0xa9059cbb...' },
    chain: 'eip155:1',
  },
  { abi: erc20Abi },
)

// {
//   selector: '0xa9059cbb',
//   functionName: 'transfer',
//   args: [
//     { name: 'to', type: 'address', value: '0x...' },
//     { name: 'amount', type: 'uint256', value: 1000000000000000000n },
//   ],
//   source: 'abi-prop',
// }

Roadmap

The starter registry (BUILTIN_REGISTRY) is empty in v0.1.0-alpha. Targets for the JSON registry data:

• Uniswap v2 / v3 / v4 routers
• Aave v3 Pool
• Compound III Comet
• Lido / EigenLayer / StakeWise
• Permit2 (Uniswap)
• 1inch v6 aggregator
• Across v3 SpokePool
• Wormhole Core / Token Bridge
• Safe Multisig
• Chainlink CCIP

Each entry ships as a JSON file under src/registry/data/ with ERC-7730 manifests for clear-signing rules.

Status

Skeleton. Implementation lands progressively as JSON registry entries are populated. The decoder API surface is stable.

License

MIT