[BUG] LiteLLM Model Does Not Throw ContextWindowOverflowException

[roeetal]

Checks

• I have updated to the lastest minor and patch version of Strands
• I have checked the documentation and this is not expected behavior
• I have searched ./issues and there are no duplicates of my issue

Strands Version

1.8.0

Python Version

3.13.1

Operating System

macOS 15.7

Installation Method

pip

Steps to Reproduce

from strands import Agent
from strands.models.litellm import LiteLLMModel
from strands.types.exceptions import ContextWindowOverflowException

model = LiteLLMModel(model_id="litellm_proxy/us.anthropic.claude-3-7-sonnet-20250219-v1:0", params={
    "api_base": "http://0.0.0.0:4000",
    "api_key": "key"
})
agent = Agent(model=model)

try:
    agent("Hi"*1000000)
except ContextWindowOverflowException as e:
    print(f"Caught context window overflow exception: {e}")
except Exception as e:
    print(f"Did not catch context window overflow exception: {e}")

Expected Behavior

Caught context window overflow exception: ...

Actual Behavior

Did not catch context window overflow exception: litellm.ContextWindowExceededError: litellm.BadRequestError: Error code: 400 - {'error': {'message': 'litellm.ContextWindowExceededError: litellm.BadRequestError: BedrockException: Context Window Error - {"message":"The model returned the following errors: Input is too long for requested model."}\nmodel=us.anthropic.claude-3-7-sonnet-20250219-v1:0. context_window_fallbacks=None. fallbacks=None.\n\nSet 'context_window_fallback' - https://docs.litellm.ai/docs/routing#fallbacks. Received Model Group=us.anthropic.claude-3-7-sonnet-20250219-v1:0\nAvailable Model Group Fallbacks=None', 'type': None, 'param': None, 'code': '400'}}

Additional Context

This is useful for conversation management and automatic handling / pruning.

Possible Solution

Implement model client exception handling similar to bedrock model: https://github.com/strands-agents/sdk-python/blob/08dc4aeaad6e75dc273d41a9898e0d08df09863b/src/strands/models/bedrock.py#L713C1-L715C63

Related Issues

No response

[Ratish1]

I'd like to contribute to this, or are you working on it @roeetal.