diff --git a/pr_agent/algo/pr_processing.py b/pr_agent/algo/pr_processing.py
index 8b319446..be3a461b 100644
--- a/pr_agent/algo/pr_processing.py
+++ b/pr_agent/algo/pr_processing.py
@@ -284,3 +284,25 @@ def find_line_number_of_relevant_line_in_file(diff_files: List[FilePatchInfo],
                         absolute_position = start2 + delta - 1
                         break
     return position, absolute_position
+
+
+def clip_tokens(text: str, max_tokens: int) -> str:
+    """
+    Clip the number of tokens in a string to a maximum number of tokens.
+
+    Args:
+        text (str): The string to clip.
+        max_tokens (int): The maximum number of tokens allowed in the string.
+
+    Returns:
+        str: The clipped string.
+    """
+    # We'll estimate the number of tokens by hueristically assuming 2.5 tokens per word
+    words = re.finditer(r'\S+', text)
+    max_words = max_tokens // 2.5
+    end_pos = None
+    for i, token in enumerate(words):
+        if i == max_words:
+            end_pos = token.start()
+            break
+    return text if end_pos is None else text[:end_pos]
\ No newline at end of file
diff --git a/pr_agent/tools/pr_reviewer.py b/pr_agent/tools/pr_reviewer.py
index 982f5000..982f18cc 100644
--- a/pr_agent/tools/pr_reviewer.py
+++ b/pr_agent/tools/pr_reviewer.py
@@ -8,7 +8,7 @@ from jinja2 import Environment, StrictUndefined
 
 from pr_agent.algo.ai_handler import AiHandler
 from pr_agent.algo.pr_processing import get_pr_diff, retry_with_fallback_models, \
-    find_line_number_of_relevant_line_in_file
+    find_line_number_of_relevant_line_in_file, clip_tokens
 from pr_agent.algo.token_handler import TokenHandler
 from pr_agent.algo.utils import convert_to_markdown, try_fix_json
 from pr_agent.config_loader import get_settings
@@ -62,6 +62,8 @@ class PRReviewer:
             "extra_instructions": get_settings().pr_reviewer.extra_instructions,
             "commit_messages_str": self.git_provider.get_commit_messages(),
         }
+        self.vars["description"] = clip_tokens(self.vars["description"], 500)
+        self.vars["commit_messages_str"] = clip_tokens(self.vars["commit_messages_str"], 500)
 
         self.token_handler = TokenHandler(
             self.git_provider.pr,