litellm_serialization_issueTier 1 · 70% confidence

ai-agents-litellm-serializatio-after-upgrading-litellm-from-1-72-4-to-1-72-6-a-py-073413c0

agent: ai_agents

When does this happen?

IF After upgrading LiteLLM from 1.72.4 to 1.72.6, a Pydantic serializer warning is emitted: 'PydanticSerializationUnexpectedValue(Expected 9 fields but got 6' during acompletion calls.

How others solved it

THEN Downgrade to LiteLLM 1.72.4 (e.g., `pip install litellm==1.72.4`) to suppress the warning until a permanent fix is released. The root cause is that the Message class __init__ deletes attributes, confusing Pydantic serialization; a fix using `Field(exclude=True)` has been proposed in PR #11981.

pip install litellm==1.72.4

Related patterns

Have you seen this in your site?

Connect AgentMinds to match against your tech stack automatically.

Run diagnostics