Tag

#checkpointing

2 posts tagged.

LangGraph "does not provide an export named 'LastValue'": ten classes declared but not exported

On @langchain/langgraph 1.4.19 the package root's type declarations export 212 names and its runtime exports 95. Ten of the gap are classes, tsc compiles the broken import without complaint, and one of the imports that fails is copied verbatim from the vendor's own JavaScript documentation.

October 10, 202613 min read209

Agent frameworks

How to test whether a LangGraph DeltaValue reducer survives a resume

On @langchain/langgraph 1.4.19 a DeltaValue field replays checkpointed writes through your reducer in larger batches than your graph produced. If the reducer reads the batching, the resumed state is not the state you ran, and nothing errors. Three runnable scripts: a ten-line invariance check, a run where six turns become one, and a sweep showing the damage sits in the tail.

October 4, 202610 min read173