migrate braintrust langchain into main pkg

[Cedric / ViaDézo1er (viadezo1er)]

DRAFT

Migration Guide: braintrust-langchain to braintrust

Before (old)

pip install braintrust-langchain

from braintrust_langchain import BraintrustCallbackHandler, set_global_handler
handler = BraintrustCallbackHandler()
set_global_handler(handler)

After (new)

pip install braintrust

Option 1: Auto-instrument (recommended)

from braintrust import auto_instrument
auto_instrument()

What stays the same

• All public APIs (BraintrustCallbackHandler, BraintrustTracer, set_global_handler, clear_global_handler) work identically
• Existing from braintrust_langchain import ... imports still work but emit a DeprecationWarning
• Full support for chains, LLMs, tools, retrievers, agents, LangGraph, streaming, and async

What to update

• Change imports from braintrust_langchain to braintrust.integrations.langchain (or use auto_instrument())
• Remove braintrust-langchain from your dependencies — braintrust now includes LangChain support with no extra package

[Cedric / ViaDézo1er (viadezo1er)]

well have to fix the CI

[Abhijeet Prasad (AbhiPrasad)]

closing in favour of #150