@langchain/core@1.1.48

Patch Changes

• #10832 1b24369 Thanks @info-arnav! - fix(core, openrouter): make CJS default re-exports callable

• #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.

• #10918 3999fab Thanks @christian-bromann! - fix(openai): stream custom tool calls through Responses API chunks