diff --git a/.gitignore b/.gitignore
index 3a5a151fb..632f2b292 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,6 +4,7 @@
 .env
 .eslintcache
 .vscode
+.idea
 coverage
 dist
 node_modules
diff --git a/__tests__/cairo1v2_typed.test.ts b/__tests__/cairo1v2_typed.test.ts
index ae31a39f3..cdcefcc35 100644
--- a/__tests__/cairo1v2_typed.test.ts
+++ b/__tests__/cairo1v2_typed.test.ts
@@ -27,7 +27,7 @@ import {
   types,
 } from '../src';
 import { hexToDecimalString } from '../src/utils/num';
-import { encodeShortString } from '../src/utils/shortString';
+import { encodeShortString, isString } from '../src/utils/shortString';
 import {
   TEST_TX_VERSION,
   compiledC1Account,
@@ -337,7 +337,7 @@ describe('Cairo 1', () => {
       const status = await cairo1Contract.echo_struct({
         val: 'simple',
       });
-      if (typeof status.val === 'string') {
+      if (isString(status.val)) {
         expect(shortString.decodeShortString(status.val)).toBe('simple');
       }
     });
diff --git a/__tests__/config/schema.ts b/__tests__/config/schema.ts
index b5b0b5649..b6d20820f 100644
--- a/__tests__/config/schema.ts
+++ b/__tests__/config/schema.ts
@@ -7,6 +7,7 @@ import libSchemas from '../schemas/lib.json';
 import providerSchemas from '../schemas/provider.json';
 import rpcSchemas from '../schemas/rpc.json';
 import sequencerSchemas from '../schemas/sequencer.json';
+import { isBigInt } from '../../src/utils/num';
 
 const matcherSchemas = [accountSchemas, libSchemas, providerSchemas, rpcSchemas, sequencerSchemas];
 const schemas = [...matcherSchemas, componentSchemas];
@@ -16,7 +17,7 @@ const jestJsonMatchers = matchersWithOptions({ schemas }, (ajv: any) => {
     keyword: 'isBigInt',
     type: 'object',
     validate: (_schema: any, data: any) => {
-      return typeof data === 'bigint' && data < 2n ** 64n && data >= 0n;
+      return isBigInt(data) && data < 2n ** 64n && data >= 0n;
     },
     errors: true,
   });
diff --git a/src/account/default.ts b/src/account/default.ts
index 23d2f185e..4101c1a10 100644
--- a/src/account/default.ts
+++ b/src/account/default.ts
@@ -56,6 +56,7 @@ import {
 import { buildUDCCall, getExecuteCalldata } from '../utils/transaction';
 import { getMessageHash } from '../utils/typedData';
 import { AccountInterface } from './interface';
+import { isString } from '../utils/shortString';
 
 export class Account extends Provider implements AccountInterface {
   public signer: SignerInterface;
@@ -76,7 +77,7 @@ export class Account extends Provider implements AccountInterface {
     super(providerOrOptions);
     this.address = address.toLowerCase();
     this.signer =
-      typeof pkOrSigner === 'string' || pkOrSigner instanceof Uint8Array
+      isString(pkOrSigner) || pkOrSigner instanceof Uint8Array
         ? new Signer(pkOrSigner)
         : pkOrSigner;
 
diff --git a/src/utils/cairoDataTypes/felt.ts b/src/utils/cairoDataTypes/felt.ts
index ffbf448b2..480f7eba1 100644
--- a/src/utils/cairoDataTypes/felt.ts
+++ b/src/utils/cairoDataTypes/felt.ts
@@ -1,7 +1,7 @@
 // TODO Convert to CairoFelt base on CairoUint256 and implement it in the codebase in the backward compatible manner
 
-import { BigNumberish, isBigInt, isHex, isStringWholeNumber } from '../num';
-import { encodeShortString, isShortString, isText } from '../shortString';
+import { BigNumberish, isBigInt, isBoolean, isHex, isStringWholeNumber } from '../num';
+import { encodeShortString, isShortString, isString, isText } from '../shortString';
 
 /**
  * Create felt Cairo type (cairo type helper)
@@ -9,29 +9,33 @@ import { encodeShortString, isShortString, isText } from '../shortString';
  */
 export function CairoFelt(it: BigNumberish): string {
   // BN or number
-  if (isBigInt(it) || (typeof it === 'number' && Number.isInteger(it))) {
+  if (isBigInt(it) || Number.isInteger(it)) {
     return it.toString();
   }
-  // string text
-  if (isText(it)) {
-    if (!isShortString(it as string))
-      throw new Error(
-        `${it} is a long string > 31 chars, felt can store short strings, split it to array of short strings`
-      );
-    const encoded = encodeShortString(it as string);
-    return BigInt(encoded).toString();
-  }
-  // hex string
-  if (typeof it === 'string' && isHex(it)) {
-    // toBN().toString
-    return BigInt(it).toString();
-  }
-  // string number (already converted), or unhandled type
-  if (typeof it === 'string' && isStringWholeNumber(it)) {
-    return it;
+
+  // Handling strings
+  if (isString(it)) {
+    // Hex strings
+    if (isHex(it)) {
+      return BigInt(it).toString();
+    }
+    // Text strings that must be short
+    if (isText(it)) {
+      if (!isShortString(it)) {
+        throw new Error(
+          `${it} is a long string > 31 chars. Please split it into an array of short strings.`
+        );
+      }
+      // Assuming encodeShortString returns a hex representation of the string
+      return BigInt(encodeShortString(it)).toString();
+    }
+    // Whole numeric strings
+    if (isStringWholeNumber(it)) {
+      return it;
+    }
   }
   // bool to felt
-  if (typeof it === 'boolean') {
+  if (isBoolean(it)) {
     return `${+it}`;
   }
 
diff --git a/src/utils/calldata/propertyOrder.ts b/src/utils/calldata/propertyOrder.ts
index d187e9472..8fc9916d3 100644
--- a/src/utils/calldata/propertyOrder.ts
+++ b/src/utils/calldata/propertyOrder.ts
@@ -22,6 +22,8 @@ import {
 } from './enum';
 import extractTupleMemberTypes from './tuple';
 
+import { isString } from '../shortString';
+
 function errorU256(key: string) {
   return Error(
     `Your object includes the property : ${key}, containing an Uint256 object without the 'low' and 'high' keys.`
@@ -92,7 +94,7 @@ export default function orderPropsByAbi(
 
   function orderArray(myArray: Array<any> | string, abiParam: string): Array<any> | string {
     const typeInArray = getArrayType(abiParam);
-    if (typeof myArray === 'string') {
+    if (isString(myArray)) {
       return myArray; // longstring
     }
     return myArray.map((myElem) => orderInput(myElem, typeInArray));
diff --git a/src/utils/calldata/requestParser.ts b/src/utils/calldata/requestParser.ts
index 091f91b85..f7fb61382 100644
--- a/src/utils/calldata/requestParser.ts
+++ b/src/utils/calldata/requestParser.ts
@@ -9,7 +9,7 @@ import {
   Tupled,
 } from '../../types';
 import { CairoUint256 } from '../cairoDataTypes/uint256';
-import { encodeShortString, isText, splitLongString } from '../shortString';
+import { encodeShortString, isString, isText, splitLongString } from '../shortString';
 import { byteArrayFromString } from './byteArray';
 import {
   felt,
@@ -266,7 +266,7 @@ export function parseCalldataField(
       if (!Array.isArray(value) && !isText(value)) {
         throw Error(`ABI expected parameter ${name} to be array or long string, got ${value}`);
       }
-      if (typeof value === 'string') {
+      if (isString(value)) {
         // long string match cairo felt*
         value = splitLongString(value);
       }
diff --git a/src/utils/calldata/validate.ts b/src/utils/calldata/validate.ts
index cf0fcfc38..56b4e28fb 100644
--- a/src/utils/calldata/validate.ts
+++ b/src/utils/calldata/validate.ts
@@ -13,8 +13,8 @@ import {
 } from '../../types';
 import assert from '../assert';
 import { CairoUint256 } from '../cairoDataTypes/uint256';
-import { isHex, toBigInt } from '../num';
-import { isLongText } from '../shortString';
+import { isBigInt, isBoolean, isHex, isNumber, toBigInt } from '../num';
+import { isLongText, isString } from '../shortString';
 import {
   getArrayType,
   isLen,
@@ -34,10 +34,10 @@ import {
 
 const validateFelt = (parameter: any, input: AbiEntry) => {
   assert(
-    typeof parameter === 'string' || typeof parameter === 'number' || typeof parameter === 'bigint',
+    isString(parameter) || isNumber(parameter) || isBigInt(parameter),
     `Validate: arg ${input.name} should be a felt typed as (String, Number or BigInt)`
   );
-  if (typeof parameter === 'string' && !isHex(parameter)) return; // shortstring
+  if (isString(parameter) && !isHex(parameter)) return; // shortstring
   const param = BigInt(parameter.toString(10));
   assert(
     // from : https://github.com/starkware-libs/starknet-specs/blob/29bab650be6b1847c92d4461d4c33008b5e50b1a/api/starknet_api_openrpc.json#L1266
@@ -47,7 +47,7 @@ const validateFelt = (parameter: any, input: AbiEntry) => {
 };
 
 const validateBytes31 = (parameter: any, input: AbiEntry) => {
-  assert(typeof parameter === 'string', `Validate: arg ${input.name} should be a string.`);
+  assert(isString(parameter), `Validate: arg ${input.name} should be a string.`);
   assert(
     parameter.length < 32,
     `Validate: arg ${input.name} cairo typed ${input.type} should be a string of less than 32 characters.`
@@ -55,20 +55,20 @@ const validateBytes31 = (parameter: any, input: AbiEntry) => {
 };
 
 const validateByteArray = (parameter: any, input: AbiEntry) => {
-  assert(typeof parameter === 'string', `Validate: arg ${input.name} should be a string.`);
+  assert(isString(parameter), `Validate: arg ${input.name} should be a string.`);
 };
 
 const validateUint = (parameter: any, input: AbiEntry) => {
-  if (typeof parameter === 'number') {
+  if (isNumber(parameter)) {
     assert(
       parameter <= Number.MAX_SAFE_INTEGER,
       `Validation: Parameter is to large to be typed as Number use (BigInt or String)`
     );
   }
   assert(
-    typeof parameter === 'string' ||
-      typeof parameter === 'number' ||
-      typeof parameter === 'bigint' ||
+    isString(parameter) ||
+      isNumber(parameter) ||
+      isBigInt(parameter) ||
       (typeof parameter === 'object' && 'low' in parameter && 'high' in parameter),
     `Validate: arg ${input.name} of cairo type ${
       input.type
@@ -142,7 +142,7 @@ const validateUint = (parameter: any, input: AbiEntry) => {
 
 const validateBool = (parameter: any, input: AbiEntry) => {
   assert(
-    typeof parameter === 'boolean',
+    isBoolean(parameter),
     `Validate: arg ${input.name} of cairo type ${input.type} should be type (Boolean)`
   );
 };
diff --git a/src/utils/contract.ts b/src/utils/contract.ts
index 7a39db24c..09d51301a 100644
--- a/src/utils/contract.ts
+++ b/src/utils/contract.ts
@@ -11,10 +11,12 @@ import { computeCompiledClassHash, computeContractClassHash } from './hash';
 import { parse } from './json';
 import { decompressProgram } from './stark';
 
+import { isString } from './shortString';
+
 export function isSierra(
   contract: CairoContract | string
 ): contract is SierraContractClass | CompiledSierra {
-  const compiledContract = typeof contract === 'string' ? parse(contract) : contract;
+  const compiledContract = isString(contract) ? parse(contract) : contract;
   return 'sierra_program' in compiledContract;
 }
 
diff --git a/src/utils/hash/classHash.ts b/src/utils/hash/classHash.ts
index 85836075d..ac9166eea 100644
--- a/src/utils/hash/classHash.ts
+++ b/src/utils/hash/classHash.ts
@@ -22,7 +22,7 @@ import { starkCurve } from '../ec';
 import { addHexPrefix, utf8ToArray } from '../encode';
 import { parse, stringify } from '../json';
 import { toHex } from '../num';
-import { encodeShortString } from '../shortString';
+import { encodeShortString, isString } from '../shortString';
 
 export function computePedersenHash(a: BigNumberish, b: BigNumberish): string {
   return starkCurve.pedersen(BigInt(a), BigInt(b));
@@ -125,8 +125,9 @@ export default function computeHintedClassHash(compiledContract: LegacyCompiledC
  * @returns format: hex-string
  */
 export function computeLegacyContractClassHash(contract: LegacyCompiledContract | string) {
-  const compiledContract =
-    typeof contract === 'string' ? (parse(contract) as LegacyCompiledContract) : contract;
+  const compiledContract = isString(contract)
+    ? (parse(contract) as LegacyCompiledContract)
+    : contract;
 
   const apiVersion = toHex(API_VERSION);
 
@@ -287,7 +288,7 @@ export function computeSierraContractClassHash(sierra: CompiledSierra) {
  * @returns format: hex-string
  */
 export function computeContractClassHash(contract: CompiledContract | string) {
-  const compiledContract = typeof contract === 'string' ? parse(contract) : contract;
+  const compiledContract = isString(contract) ? parse(contract) : contract;
 
   if ('sierra_program' in compiledContract) {
     return computeSierraContractClassHash(compiledContract as CompiledSierra);
diff --git a/src/utils/num.ts b/src/utils/num.ts
index d3e9f9c45..544cb3bab 100644
--- a/src/utils/num.ts
+++ b/src/utils/num.ts
@@ -181,3 +181,23 @@ export function addPercent(number: BigNumberish, percent: number) {
   const bigIntNum = BigInt(number);
   return bigIntNum + (bigIntNum * BigInt(percent)) / 100n;
 }
+
+/**
+ * Check if a value is a number.
+ *
+ * @param {unknown} value - The value to check.
+ * @return {boolean} Returns true if the value is a number, otherwise returns false.
+ */
+export function isNumber(value: unknown): value is number {
+  return typeof value === 'number';
+}
+
+/**
+ * Checks if a given value is of boolean type.
+ *
+ * @param {unknown} value - The value to check.
+ * @return {boolean} - True if the value is of boolean type, false otherwise.
+ */
+export function isBoolean(value: unknown): value is boolean {
+  return typeof value === 'boolean';
+}
diff --git a/src/utils/provider.ts b/src/utils/provider.ts
index bd125b8df..59983e23d 100644
--- a/src/utils/provider.ts
+++ b/src/utils/provider.ts
@@ -21,8 +21,9 @@ import { ETransactionVersion } from '../types/api';
 import { isSierra } from './contract';
 import { formatSpaces } from './hash';
 import { parse, stringify } from './json';
-import { isHex, toHex } from './num';
+import { isBigInt, isHex, isNumber, toHex } from './num';
 import { compressProgram } from './stark';
+import { isString } from './shortString';
 
 /**
  * Helper - Async Sleep for 'delay' time
@@ -53,8 +54,7 @@ export function createSierraContractClass(contract: CompiledSierra): SierraContr
  * (CompiledContract or string) -> ContractClass
  */
 export function parseContract(contract: CompiledContract | string): ContractClass {
-  const parsedContract =
-    typeof contract === 'string' ? (parse(contract) as CompiledContract) : contract;
+  const parsedContract = isString(contract) ? (parse(contract) as CompiledContract) : contract;
 
   if (!isSierra(contract)) {
     return {
@@ -85,7 +85,7 @@ export const getDefaultNodeUrl = (networkName?: NetworkName, mute: boolean = fal
  * [Reference](https://github.com/starkware-libs/cairo-lang/blob/fc97bdd8322a7df043c87c371634b26c15ed6cee/src/starkware/starknet/services/api/feeder_gateway/feeder_gateway_client.py#L148-L153)
  */
 export function formatHash(hashValue: BigNumberish): string {
-  if (typeof hashValue === 'string') return hashValue;
+  if (isString(hashValue)) return hashValue;
   return toHex(hashValue);
 }
 
@@ -111,19 +111,17 @@ export class Block {
   tag: BlockIdentifier = null;
 
   private setIdentifier(__identifier: BlockIdentifier) {
-    if (typeof __identifier === 'string' && isHex(__identifier)) {
-      this.hash = __identifier;
-    } else if (typeof __identifier === 'bigint') {
+    if (isString(__identifier)) {
+      if (isHex(__identifier)) {
+        this.hash = __identifier;
+      } else if (validBlockTags.includes(__identifier as BlockTag)) {
+        this.tag = __identifier;
+      }
+    } else if (isBigInt(__identifier)) {
       this.hash = toHex(__identifier);
-    } else if (typeof __identifier === 'number') {
+    } else if (isNumber(__identifier)) {
       this.number = __identifier;
-    } else if (
-      typeof __identifier === 'string' &&
-      validBlockTags.includes(__identifier as BlockTag)
-    ) {
-      this.tag = __identifier;
     } else {
-      // default
       this.tag = BlockTag.pending;
     }
   }
diff --git a/src/utils/responseParser/rpc.ts b/src/utils/responseParser/rpc.ts
index 96c82387c..9ae3ce45d 100644
--- a/src/utils/responseParser/rpc.ts
+++ b/src/utils/responseParser/rpc.ts
@@ -19,6 +19,7 @@ import {
 import { toBigInt } from '../num';
 import { estimateFeeToBounds, estimatedFeeToMaxFee } from '../stark';
 import { ResponseParser } from '.';
+import { isString } from '../shortString';
 
 export class RPCResponseParser
   implements
@@ -57,7 +58,7 @@ export class RPCResponseParser
   public parseTransactionReceipt(res: TransactionReceipt): GetTransactionReceiptResponse {
     // HOTFIX RPC 0.5 to align with RPC 0.6
     // This case is RPC 0.5. It can be only v2 thx with FRI units
-    if ('actual_fee' in res && typeof res.actual_fee === 'string') {
+    if ('actual_fee' in res && isString(res.actual_fee)) {
       return {
         ...(res as GetTransactionReceiptResponse),
         actual_fee: {
@@ -113,7 +114,7 @@ export class RPCResponseParser
   public parseContractClassResponse(res: ContractClassPayload): ContractClassResponse {
     return {
       ...(res as ContractClassResponse),
-      abi: typeof res.abi === 'string' ? JSON.parse(res.abi) : res.abi,
+      abi: isString(res.abi) ? JSON.parse(res.abi) : res.abi,
     };
   }
 }
diff --git a/src/utils/shortString.ts b/src/utils/shortString.ts
index bbcc27be6..bd4d8953a 100644
--- a/src/utils/shortString.ts
+++ b/src/utils/shortString.ts
@@ -24,11 +24,21 @@ export function isDecimalString(str: string): boolean {
   return /^[0-9]*$/i.test(str);
 }
 
+/**
+ * Checks if a given value is a string.
+ *
+ * @param {unknown} value - The value to be checked.
+ * @return {boolean} - Returns true if the value is a string, false otherwise.
+ */
+export function isString(value: unknown): value is string {
+  return typeof value === 'string';
+}
+
 /**
  * Test if value is a free-from string text, and not a hex string or number string
  */
 export function isText(val: any) {
-  return typeof val === 'string' && !isHex(val) && !isStringWholeNumber(val);
+  return isString(val) && !isHex(val) && !isStringWholeNumber(val);
 }
 
 /**
diff --git a/src/utils/stark.ts b/src/utils/stark.ts
index ec14eb36c..65955fc6b 100644
--- a/src/utils/stark.ts
+++ b/src/utils/stark.ts
@@ -18,8 +18,10 @@ import {
   addPercent,
   bigNumberishArrayToDecimalStringArray,
   bigNumberishArrayToHexadecimalStringArray,
+  isBigInt,
   toHex,
 } from './num';
+import { isString } from './shortString';
 
 /**
  * Compress compiled Cairo program
@@ -28,7 +30,7 @@ import {
  * @param jsonProgram Representing the compiled cairo program
  */
 export function compressProgram(jsonProgram: Program | string): CompressedProgram {
-  const stringified = typeof jsonProgram === 'string' ? jsonProgram : stringify(jsonProgram);
+  const stringified = isString(jsonProgram) ? jsonProgram : stringify(jsonProgram);
   const compressedProgram = gzip(stringified);
   return btoaUniversal(compressedProgram);
 }
@@ -107,7 +109,7 @@ export function estimateFeeToBounds(
   amountOverhead: number = feeMarginPercentage.L1_BOUND_MAX_AMOUNT,
   priceOverhead: number = feeMarginPercentage.L1_BOUND_MAX_PRICE_PER_UNIT
 ): ResourceBounds {
-  if (typeof estimate === 'bigint') {
+  if (isBigInt(estimate)) {
     return {
       l2_gas: { max_amount: '0x0', max_price_per_unit: '0x0' },
       l1_gas: { max_amount: '0x0', max_price_per_unit: '0x0' },
diff --git a/src/utils/typedData.ts b/src/utils/typedData.ts
index 16413f0c2..1df8d393b 100644
--- a/src/utils/typedData.ts
+++ b/src/utils/typedData.ts
@@ -17,7 +17,7 @@ import {
 } from './hash';
 import { MerkleTree } from './merkle';
 import { isHex, toHex } from './num';
-import { encodeShortString } from './shortString';
+import { encodeShortString, isString } from './shortString';
 
 /** @deprecated prefer importing from 'types' over 'typedData' */
 export * from '../types/typedData';
@@ -79,7 +79,7 @@ function getHex(value: BigNumberish): string {
   try {
     return toHex(value);
   } catch (e) {
-    if (typeof value === 'string') {
+    if (isString(value)) {
       return toHex(encodeShortString(value));
     }
     throw new Error(`Invalid BigNumberish: ${value}`);