Breaking Changes: OneLLM Exception Renames (PR #9 + PR #10)

This document lists all breaking changes introduced by PR #9 and PR #10 for the muxi runtime droid to handle.

Summary

Two categories of renames:

1. Builtin shadowing fix (PR #9): Renamed exceptions that shadowed Python builtins
2. Brand rename (PR #10): Renamed MuxiLLM prefix to OneLLM

Exception Class Renames

Old Name	New Name	Reason
TimeoutError	RequestTimeoutError	Shadowed Python builtin TimeoutError
PermissionError	PermissionDeniedError	Shadowed Python builtin PermissionError
MuxiLLMError	OneLLMError	Brand rename

Import Changes Required

Before

from onellm.errors import TimeoutError, PermissionError, MuxiLLMError

try:
    response = ChatCompletion.create(...)
except TimeoutError:
    # handle timeout
except PermissionError:
    # handle permission denied
except MuxiLLMError:
    # handle any onellm error

After

from onellm.errors import RequestTimeoutError, PermissionDeniedError, OneLLMError

try:
    response = ChatCompletion.create(...)
except RequestTimeoutError:
    # handle timeout
except PermissionDeniedError:
    # handle permission denied
except OneLLMError:
    # handle any onellm error

Affected Files in onellm Package

These files have been updated internally:

• onellm/errors.py - Class definitions
• onellm/__init__.py - Exports
• onellm/providers/openai.py
• onellm/providers/azure.py
• onellm/providers/anthropic.py
• onellm/providers/mistral.py
• onellm/providers/bedrock.py
• onellm/utils/retry.py
• onellm/utils/fallback.py
• onellm/utils/streaming.py

Impact Assessment

Low impact expected for muxi runtime because:

1. The runtime likely catches OneLLMError (base class) rather than specific subclasses
2. The builtin shadowing fix (TimeoutError/PermissionError) is actually a bug fix - catching Python’s builtin TimeoutError would have caught unrelated timeout exceptions

Search Patterns for Downstream Code

To find code that needs updating, search for:

# Find old exception imports
rg "from onellm.errors import.*TimeoutError"
rg "from onellm.errors import.*PermissionError"
rg "from onellm.errors import.*MuxiLLMError"
rg "from onellm import.*MuxiLLMError"

# Find exception catches
rg "except.*TimeoutError"
rg "except.*PermissionError"
rg "except.*MuxiLLMError"

Backward Compatibility (Not Implemented)

These PRs do not include backward compatibility aliases. If needed, add to onellm/errors.py:

# Deprecated aliases for backward compatibility
TimeoutError = RequestTimeoutError
PermissionError = PermissionDeniedError
MuxiLLMError = OneLLMError

And add deprecation warnings in __init__.py if desired.