Exporting function signatures and especially error signatures which are still not properly showcased on etherscan and others is useful thing to have so you can match your errors or your function calls. To do that I made a custom hardhat task that will do that if you pass it name of the contract. Put this into tasks folder

import { task } from 'hardhat/config';

task('sigs', 'Generate ABI signatures for errors and functions')
  .addParam('c', 'Name of the contract for which to generate ABI data')
  .addOptionalParam('f', 'Name of Solidity file where contract is stored')
  .setAction(async (taskArgs: any, { ethers }) => {
    // If 'f' is not defined, use the value of 'c' for it
    const fileName = taskArgs.f || taskArgs.c;

    // Load the contract ABI based on the contract name
    const ABI = (await import(`../artifacts/src/${fileName}.sol/${taskArgs.c}.json`)).abi;

    const prepareData = (e: { name: string; inputs: { type: string }[] }) =>
      `${e.name}(${e.inputs.map((param) => param.type)})`;
    const encodeSelector = (f: string) => ethers.utils.id(f).slice(0, 10);

    // Parse ABI
    const output = ABI.filter((e: any) => ['function', 'error'].includes(e.type)).flatMap(
      (e: any) => `${encodeSelector(prepareData(e))}: ${prepareData(e)}`
    );

    console.log(output);
  });

And in your hardhat config add that file or folder with import

import './tasks/signatures';

you can now just run

hh  sigs -c myContract 

And you will get nice output of the functions/errors and corresponding signatures.If you need some help with making tasks, there is nice link with some other examples here

https://betterprogramming.pub/create-a-smart-contract-developmentworkflow-using-hardhat-tasks-e5d80d819cea

You might find this tool also useful for searching function signatures

https://www.4byte.directory/

or this if you need to quickly get one from some function definition

https://piyolab.github.io/playground/ethereum/getEncodedFunctionSignature/

Code is JS/TS so you can easily adjust this if you want to some other framework or just plain JS script.

Exporting function signatures and especially error signatures which are still not properly showcased on etherscan and others is useful thing to have so you can match your errors or your function calls. To do that I made a custom hardhat task that will do that if you pass it name of the contract. Put this into tasks folder

import { task } from 'hardhat/config';

task('sigs', 'Generate ABI signatures for errors and functions')
  .addParam('c', 'Name of the contract for which to generate ABI data')
  .addOptionalParam('f', 'Name of Solidity file where contract is stored')
  .setAction(async (taskArgs: any, { ethers }) => {
    // If 'f' is not defined, use the value of 'c' for it
    const fileName = taskArgs.f || taskArgs.c;

    // Load the contract ABI based on the contract name
    const ABI = (await import(`../artifacts/src/${fileName}.sol/${taskArgs.c}.json`)).abi;

    const prepareData = (e: { name: string; inputs: { type: string }[] }) =>
      `${e.name}(${e.inputs.map((param) => param.type)})`;
    const encodeSelector = (f: string) => ethers.utils.id(f).slice(0, 10);

    // Parse ABI
    const output = ABI.filter((e: any) => ['function', 'error'].includes(e.type)).flatMap(
      (e: any) => `${encodeSelector(prepareData(e))}: ${prepareData(e)}`
    );

    console.log(output);
  });

And in your hardhat config add that file or folder with import

import './tasks/signatures';

you can now just run

hh  sigs -c myContract 

And you will get nice output of the functions/errors and corresponding signatures.If you need some help with making tasks, there is nice link with some other examples here

https://betterprogramming.pub/create-a-smart-contract-developmentworkflow-using-hardhat-tasks-e5d80d819cea

You might find this tool also useful for searching function signatures

https://www.4byte.directory/

or this if you need to quickly get one from some function definition

https://piyolab.github.io/playground/ethereum/getEncodedFunctionSignature/

Code is JS/TS so you can easily adjust this if you want to some other framework or just plain JS script.