FuelLabs/fuels-ts · error · FuelError

ABI_MAIN_METHOD_MISSING

ABI_MAIN_METHOD_MISSING

Error message

ABI doesn't have a 'main()' method.

What it means

The script template requires the ABI to declare a `main` function whose attributes (prefixedInputs, output) drive the generated script wrapper. If abi.functions.find for 'main' returns undefined, the script cannot be typed and the generator aborts.

Source

Thrown at packages/abi-typegen/src/templates/script/main.ts:30

export function renderMainTemplate(params: { abi: Abi; versions: BinaryVersions }) {
  const { abi, versions } = params;

  const { types, configurables } = abi;

  const {
    rawContents,
    capitalizedName,
    hexlifiedBinContents: hexlifiedBinString,
    commonTypesInUse,
  } = params.abi;

  const abiJsonString = JSON.stringify(rawContents, null, 2);

  const func = abi.functions.find((f) => f.name === 'main');

  if (!func) {
    throw new FuelError(ErrorCode.ABI_MAIN_METHOD_MISSING, `ABI doesn't have a 'main()' method.`);
  }

  const { enums } = formatEnums({ types });
  const { structs } = formatStructs({ types });
  const { imports } = formatImports({
    types,
    baseMembers: ['Script as __Script', 'Account', 'decompressBytecode'],
  });

  const { prefixedInputs: inputs, output } = func.attributes;

  const text = renderHbsTemplate({
    template: mainTemplate,
    versions,
    data: {
      inputs,
      output,
      structs,

View on GitHub (pinned to b3f37c91ac)

Solutions

1. Confirm the ABI is a script ABI and exposes a function named exactly 'main'.
2. Recompile the Sway script with forc and regenerate the ABI.
3. Pass the correct programType matching the ABI.

function assertScriptMain(abi: JsonAbi) {
  if (!abi.functions.some(f => f.name === 'main')) {
    throw new Error('script ABI must declare a main() function');
  }
}

function isScriptAbi(abi: JsonAbi): boolean {
  return abi.functions.some(f => f.name === 'main');
}

When it happens

Trigger: Running typegen with programType=SCRIPT against an ABI without a 'main' function; using a contract ABI (which may have arbitrary function names) for script generation; renamed Sway entrypoint.

Common situations: Wrong ABI for the programType; ABI from a Sway script whose main was renamed; mixing contract and script ABIs in a monorepo.

Related errors

• ABI_MAIN_METHOD_MISSING
• JSON_ABI_ERROR
• TYPE_ID_NOT_FOUND
• BIN_FILE_NOT_FOUND
• INVALID_COMPONENT

AI-assisted analysis of FuelLabs/fuels-ts@b3f37c91ac (2026-08-12). Data as JSON: /api/errors/0b8fc29d395d3d42. Report an issue: GitHub.