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npm · #4362 most downloaded on npm
Core LangChain.js abstractions and schemas
Last release 5 days ago
12 Sep 2026
Ships fairly regularly
a new release about every 2 weeks
Nearly every release is documented
notes for 59 of the last 60 stable releases
Nothing withdrawn
no release was ever pulled
3 years old
352 releases · first in 2023
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One column per month.
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### Minor Changes - #10924 `2e28115` Thanks @christian-bromann! - feat(perplexity): add native completions streamEvents events
2e28115 Thanks @christian-bromann! - feat(perplexity): add native completions streamEvents events#10666 2bb55b0 Thanks @hnustwjj! - feat(openrouter): surface reasoning content as v1 standard content blocks
convertOpenRouterResponseToBaseMessage and
convertOpenRouterDeltaToBaseMessageChunk now copy OpenRouter's
reasoning (flat string) and reasoning_details (structured array) fields
onto additional_kwargs.reasoning_content / additional_kwargs.reasoning_details.
A new ChatOpenRouterTranslator is registered in @langchain/core under
the "openrouter" provider key so AIMessage.contentBlocks emits standard
{type: "reasoning"} blocks alongside text and tool calls.
Previously, reasoning text returned by reasoning-capable models routed
through OpenRouter (DeepSeek R1, Minimax M2, Claude extended thinking,
o-series, etc.) was silently dropped: only the reasoning_tokens count
was preserved via usage_metadata. Consumers using standard content blocks
(including the frontend agent UI patterns shown in the docs) could not
display the model's chain of thought.
#10832 1b24369 Thanks @info-arnav! - fix(core, openrouter): make CJS default re-exports callable
Updated dependencies [3999fab, fce9ab4]:
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Updated dependencies [ ffebdc2 ]:
ffebdc2]:
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Updated dependencies [ 6bd3a18 , 7d6e1b0 , 80c5c93 ]:
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