Description

Fix type mismatch in Langchain.update() where vector and payload are passed as scalars to insert(), which expects List[List[float]] and List[Dict]. This causes AttributeError: 'str' object has no attribute 'get' at runtime when updating vectors through the LangChain adapter.

Wraps both parameters in lists before passing to insert().

Fixes #3767

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

• Unit Test

Added regression test test_update_wraps_vector_and_payload_in_lists that verifies update() correctly wraps vector and payload in lists before calling insert(). All 11 existing + new
tests pass.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Maintainer Checklist

• closes Type Mismatch in Langchain Vector Store Adapter's update Method #3767
• Made sure Checks passed