diff --git a/gliner_inference_server/helpers.py b/gliner_inference_server/helpers.py
index 0eaf3a6..40d0f87 100644
--- a/gliner_inference_server/helpers.py
+++ b/gliner_inference_server/helpers.py
@@ -1,5 +1,9 @@
 from fastapi import HTTPException, status
 from typing import List, Optional, Union, Dict, Any, Tuple
+import os
+
+
+MAX_TEXT_LENGTH = int(os.getenv("MAX_TEXT_LENGTH", "1000"))
 
 
 def validate_single_or_batch(text: Optional[str], texts: Optional[List[str]]):
@@ -69,6 +73,48 @@ def validate_single_or_batch(text: Optional[str], texts: Optional[List[str]]):
     return text if text is not None else texts
 
 
+def validate_prompt_and_text_length(prompt: Optional[str], text: Optional[str], texts: Optional[List[str]]):
+    """Validate that combined prompt and text length doesn't exceed maximum"""
+    prompt_length = len(prompt) if prompt else 0
+
+    if text:
+        combined_length = prompt_length + len(text)
+        if combined_length > MAX_TEXT_LENGTH:
+            raise HTTPException(
+                status_code=status.HTTP_400_BAD_REQUEST,
+                detail={
+                    "error": {
+                        "code": "INVALID_INPUT",
+                        "message": f"Combined prompt and text length ({combined_length}) exceeds maximum length of {MAX_TEXT_LENGTH}",
+                        "details": {
+                            "prompt_length": prompt_length,
+                            "text_length": len(text),
+                            "max_length": MAX_TEXT_LENGTH
+                        }
+                    }
+                }
+            )
+
+    if texts:
+        for i, txt in enumerate(texts):
+            combined_length = prompt_length + len(txt)
+            if combined_length > MAX_TEXT_LENGTH:
+                raise HTTPException(
+                    status_code=status.HTTP_400_BAD_REQUEST,
+                    detail={
+                        "error": {
+                            "code": "INVALID_INPUT",
+                            "message": f"Combined prompt and texts[{i}] length ({combined_length}) exceeds maximum length of {MAX_TEXT_LENGTH}",
+                            "details": {
+                                "prompt_length": prompt_length,
+                                "text_index": i,
+                                "text_length": len(txt),
+                                "max_length": MAX_TEXT_LENGTH
+                            }
+                        }
+                    }
+                )
+
 def handle_error(e: Exception):
     """Convert exceptions to consistent error format"""
     if isinstance(e, HTTPException):
diff --git a/gliner_inference_server/main.py b/gliner_inference_server/main.py
index fcac631..eb412f1 100644
--- a/gliner_inference_server/main.py
+++ b/gliner_inference_server/main.py
@@ -126,6 +126,7 @@ async def general_extraction(request: GeneralRequest):
     """
     try:
         input_data = validate_single_or_batch(request.text, request.texts)
+        validate_prompt_and_text_length(request.prompt, request.text, request.texts)
         is_batch = isinstance(input_data, list)
 
         # Process batch or single
@@ -190,6 +191,7 @@ async def relation_extraction(request: RelationExtractionRequest):
     """
     try:
         input_data = validate_single_or_batch(request.text, request.texts)
+        validate_prompt_and_text_length(request.prompt, request.text, request.texts)
         is_batch = isinstance(input_data, list)
 
         texts_to_process = input_data if is_batch else [input_data]
@@ -383,6 +385,7 @@ async def summarization(request: SummarizationRequest):
     """
     try:
         input_data = validate_single_or_batch(request.text, request.texts)
+        validate_prompt_and_text_length(request.prompt, request.text, request.texts)
         is_batch = isinstance(input_data, list)
 
         texts_to_process = input_data if is_batch else [input_data]