diff --git a/vllm/entrypoints/openai/serving_engine.py b/vllm/entrypoints/openai/serving_engine.py
index 5e26eac77c85..dc1933fd2e5d 100644
--- a/vllm/entrypoints/openai/serving_engine.py
+++ b/vllm/entrypoints/openai/serving_engine.py
@@ -1,8 +1,7 @@
 import json
 from dataclasses import dataclass
 from http import HTTPStatus
-from typing import (Dict, Iterable, Iterator, List, Literal, Optional, Tuple,
-                    TypedDict, Union, cast)
+from typing import Dict, Iterable, Iterator, List, Optional, Tuple, Union
 
 from pydantic import Field
 from transformers import PreTrainedTokenizer, PreTrainedTokenizerFast
@@ -15,6 +14,7 @@
                                               EmbeddingRequest, ErrorResponse,
                                               LogProbs, ModelCard, ModelList,
                                               ModelPermission)
+from vllm.inputs import parse_and_batch_prompt
 from vllm.logger import init_logger
 from vllm.lora.request import LoRARequest
 from vllm.sequence import Logprob
@@ -23,16 +23,6 @@
 logger = init_logger(__name__)
 
 
-class InputString(TypedDict):
-    text: str
-    is_tokens: Literal[False]
-
-
-class InputTokens(TypedDict):
-    text: List[int]
-    is_tokens: Literal[True]
-
-
 @dataclass
 class LoRAModulePath:
     name: str
@@ -304,38 +294,6 @@ def _tokenize_prompt_inputs(
                     truncate_prompt_tokens=truncate_prompt_tokens,
                 )
 
-    def _parse_prompt_input_or_inputs(
-        self,
-        input_or_inputs: Union[str, List[str], List[int], List[List[int]]],
-    ) -> List[Union[InputString, InputTokens]]:
-        if isinstance(input_or_inputs, str):
-            # case 1: a string
-            return [InputString(text=input_or_inputs, is_tokens=False)]
-
-        if isinstance(input_or_inputs, list):
-            if len(input_or_inputs) == 0:
-                raise ValueError("please provide at least one prompt")
-            if isinstance(input_or_inputs[0], str):
-                # case 2: array of strings
-                return [
-                    InputString(text=elem, is_tokens=False)
-                    for elem in cast(List[str], input_or_inputs)
-                ]
-            if isinstance(input_or_inputs[0], int):
-                # case 3: array of tokens
-                elem = cast(List[int], input_or_inputs)
-                return [InputTokens(text=elem, is_tokens=True)]
-            if isinstance(input_or_inputs[0], list) and isinstance(
-                    input_or_inputs[0][0], int):
-                # case 4: array of token arrays
-                return [
-                    InputTokens(text=elem, is_tokens=True)
-                    for elem in cast(List[List[int]], input_or_inputs)
-                ]
-
-        raise ValueError("prompt must be a string, array of strings, "
-                         "array of tokens, or array of token arrays")
-
     def _tokenize_prompt_input_or_inputs(
         self,
         request: Union[ChatCompletionRequest, CompletionRequest,
@@ -352,8 +310,7 @@ def _tokenize_prompt_input_or_inputs(
         """
         tokenizer = self.tokenizer
 
-        for prompt_input in self._parse_prompt_input_or_inputs(
-                input_or_inputs):
+        for prompt_input in parse_and_batch_prompt(input_or_inputs):
             # Although our type checking is based on mypy,
             # VSCode Pyright extension should still work properly
             # "is True" is required for Pyright to perform type narrowing
@@ -361,7 +318,7 @@ def _tokenize_prompt_input_or_inputs(
             if prompt_input["is_tokens"] is False:
                 yield self._normalize_prompt_text_to_input(
                     request,
-                    prompt=prompt_input["text"],
+                    prompt=prompt_input["content"],
                     tokenizer=tokenizer,
                     truncate_prompt_tokens=truncate_prompt_tokens,
                     add_special_tokens=add_special_tokens,
@@ -369,7 +326,7 @@ def _tokenize_prompt_input_or_inputs(
             else:
                 yield self._normalize_prompt_tokens_to_input(
                     request,
-                    prompt_ids=prompt_input["text"],
+                    prompt_ids=prompt_input["content"],
                     tokenizer=tokenizer,
                     truncate_prompt_tokens=truncate_prompt_tokens,
                 )