# @langchain/core ## 1.1.11 ### Patch Changes - [#9753](https://github.com/langchain-ai/langchainjs/pull/9753) [`a46a249`](https://github.com/langchain-ai/langchainjs/commit/a46a24983fd0fea649d950725a2673b3c435275f) Thanks [@christian-bromann](https://github.com/christian-bromann)! - fix(core): allow shared object references in serialization ## 1.1.10 ### Patch Changes - [#9746](https://github.com/langchain-ai/langchainjs/pull/9746) [`817fc9a`](https://github.com/langchain-ai/langchainjs/commit/817fc9a56d4699f3563a6e153b13eadf7bcc661b) Thanks [@bracesproul](https://github.com/bracesproul)! - fix: `_mergeDicts` error when merging undefined values ## 1.1.9 ### Patch Changes - [#9725](https://github.com/langchain-ai/langchainjs/pull/9725) [`56600b9`](https://github.com/langchain-ai/langchainjs/commit/56600b94f8e185f44d4288b7a9b66c55778938dd) Thanks [@Orenoid](https://github.com/Orenoid)! - fix(langchain): update merge logic for numeric values in `mergeDicts` - [#9736](https://github.com/langchain-ai/langchainjs/pull/9736) [`dc5c2ac`](https://github.com/langchain-ai/langchainjs/commit/dc5c2ac00f86dd2feeba9843d708926a5f38202e) Thanks [@hntrl](https://github.com/hntrl)! - fix(core): handle circular references in `load` - [#9739](https://github.com/langchain-ai/langchainjs/pull/9739) [`c28d24a`](https://github.com/langchain-ai/langchainjs/commit/c28d24a8770f6d0e543cde116b0e38b3baf21301) Thanks [@christian-bromann](https://github.com/christian-bromann)! - fix(core): use getBufferString for message summarization - [#9702](https://github.com/langchain-ai/langchainjs/pull/9702) [`bfcb87d`](https://github.com/langchain-ai/langchainjs/commit/bfcb87d23c580c7881f650960a448fe2e54a30b3) Thanks [@christian-bromann](https://github.com/christian-bromann)! - fix(core): improve interop with Zod ## 1.1.8 ### Patch Changes - [#9707](https://github.com/langchain-ai/langchainjs/pull/9707) [`e5063f9`](https://github.com/langchain-ai/langchainjs/commit/e5063f9c6e9989ea067dfdff39262b9e7b6aba62) Thanks [@hntrl](https://github.com/hntrl)! - add security hardening for `load` - [#9684](https://github.com/langchain-ai/langchainjs/pull/9684) [`8996647`](https://github.com/langchain-ai/langchainjs/commit/89966470e8c0b112ce4f9a326004af6a4173f9e6) Thanks [@christian-bromann](https://github.com/christian-bromann)! - fix(core): document purpose of name in base message ## 1.1.7 ### Patch Changes - [#9686](https://github.com/langchain-ai/langchainjs/pull/9686) [`df9c42b`](https://github.com/langchain-ai/langchainjs/commit/df9c42b3ab61b85309ab47256e1d93c3188435ee) Thanks [@hntrl](https://github.com/hntrl)! - add usage_metadata to metadata in LangChainTracer - [#9665](https://github.com/langchain-ai/langchainjs/pull/9665) [`8d2982b`](https://github.com/langchain-ai/langchainjs/commit/8d2982bb94c0f4e4314ace3cc98a1ae87571b1ed) Thanks [@jacoblee93](https://github.com/jacoblee93)! - feat(core): Make runnable transform trace in a single payload in LangChainTracer - [#9675](https://github.com/langchain-ai/langchainjs/pull/9675) [`af664be`](https://github.com/langchain-ai/langchainjs/commit/af664becc0245b2315ea2f784c9a6c1d7622dbb4) Thanks [@jacoblee93](https://github.com/jacoblee93)! - Bump LangSmith dep to 0.4.0 - [#9673](https://github.com/langchain-ai/langchainjs/pull/9673) [`ffb2402`](https://github.com/langchain-ai/langchainjs/commit/ffb24026cd93e58219519ee24c6e23ea57cb5bde) Thanks [@hntrl](https://github.com/hntrl)! - add `context` utility ## 1.1.6 ### Patch Changes - [#9668](https://github.com/langchain-ai/langchainjs/pull/9668) [`a7b2a7d`](https://github.com/langchain-ai/langchainjs/commit/a7b2a7db5ef57df3731ae6c9931f4b663e909505) Thanks [@bracesproul](https://github.com/bracesproul)! - fix: Cannot merge two undefined objects error - [#9657](https://github.com/langchain-ai/langchainjs/pull/9657) [`a496c5f`](https://github.com/langchain-ai/langchainjs/commit/a496c5fc64d94cc0809216325b0f1bfde3f92c45) Thanks [@dqbd](https://github.com/dqbd)! - fix(core): avoid writing to TransformStream in EventStreamCallbackHandler when underlying ReadableStream is closed - [#9658](https://github.com/langchain-ai/langchainjs/pull/9658) [`1da1325`](https://github.com/langchain-ai/langchainjs/commit/1da1325aea044fb37af54a9de1f4ae0b9f47d4a2) Thanks [@dqbd](https://github.com/dqbd)! - fix(core): ensure streaming test chat models respect AbortSignal ## 1.1.5 ### Patch Changes - [#9641](https://github.com/langchain-ai/langchainjs/pull/9641) [`005c729`](https://github.com/langchain-ai/langchainjs/commit/005c72903bcdf090e0f4c58960c8c243481f9874) Thanks [@christian-bromann](https://github.com/christian-bromann)! - fix(community/core): various security fixes - [#7907](https://github.com/langchain-ai/langchainjs/pull/7907) [`ab78246`](https://github.com/langchain-ai/langchainjs/commit/ab782462753e6c3ae5d55c0c251f795af32929d5) Thanks [@jasonphillips](https://github.com/jasonphillips)! - fix(core): handle subgraph nesting better in graph_mermaid - [#9589](https://github.com/langchain-ai/langchainjs/pull/9589) [`8cc81c7`](https://github.com/langchain-ai/langchainjs/commit/8cc81c7cee69530f7a6296c69123edbe227b2fce) Thanks [@nathannewyen](https://github.com/nathannewyen)! - test(core): add test for response_metadata in streamEvents - [#9644](https://github.com/langchain-ai/langchainjs/pull/9644) [`f32e499`](https://github.com/langchain-ai/langchainjs/commit/f32e4991d0e707324e3f6af287a1ee87ab833b7e) Thanks [@hntrl](https://github.com/hntrl)! - add bindTools to FakeListChatModel - [#9508](https://github.com/langchain-ai/langchainjs/pull/9508) [`a28d83d`](https://github.com/langchain-ai/langchainjs/commit/a28d83d49dd1fd31e67b52a44abc70f2cc2a2026) Thanks [@shubham-021](https://github.com/shubham-021)! - Fix toFormattedString() to properly display nested objects in tool call arguments instead of [object Object] - [#9165](https://github.com/langchain-ai/langchainjs/pull/9165) [`2e5ad70`](https://github.com/langchain-ai/langchainjs/commit/2e5ad70d16c1f13eaaea95336bbe2ec4a4a4954a) Thanks [@pawel-twardziak](https://github.com/pawel-twardziak)! - fix(mcp-adapters): preserve timeout from RunnableConfig in MCP tool calls - [#9647](https://github.com/langchain-ai/langchainjs/pull/9647) [`e456c66`](https://github.com/langchain-ai/langchainjs/commit/e456c661aa1ab8f1ed4a98c40616f5a13270e88e) Thanks [@hntrl](https://github.com/hntrl)! - handle missing parent runs in tracer to prevent LangSmith 400 errors - [#9597](https://github.com/langchain-ai/langchainjs/pull/9597) [`1cfe603`](https://github.com/langchain-ai/langchainjs/commit/1cfe603e97d8711343ae5f1f5a75648e7bd2a16e) Thanks [@hntrl](https://github.com/hntrl)! - use uuid7 for run ids ## 1.1.4 ### Patch Changes - [#9575](https://github.com/langchain-ai/langchainjs/pull/9575) [`0bade90`](https://github.com/langchain-ai/langchainjs/commit/0bade90ed47c7988ed86f1e695a28273c7b3df50) Thanks [@hntrl](https://github.com/hntrl)! - bin p-retry - [#9574](https://github.com/langchain-ai/langchainjs/pull/9574) [`6c40d00`](https://github.com/langchain-ai/langchainjs/commit/6c40d00e926f377d249c2919549381522eac8ed1) Thanks [@hntrl](https://github.com/hntrl)! - Revert "fix(@langchain/core): update and bundle dependencies (#9534)" ## 1.1.3 ### Patch Changes - [#9534](https://github.com/langchain-ai/langchainjs/pull/9534) [`bd2c46e`](https://github.com/langchain-ai/langchainjs/commit/bd2c46e09e661d9ac766c09e71bc6687d6fc811c) Thanks [@christian-bromann](https://github.com/christian-bromann)! - fix(@langchain/core): update and bundle `p-retry`, `ansi-styles`, `camelcase` and `decamelize` dependencies - [#9544](https://github.com/langchain-ai/langchainjs/pull/9544) [`487378b`](https://github.com/langchain-ai/langchainjs/commit/487378bf14277659c8ca0ef06ea0f9836b818ff4) Thanks [@hntrl](https://github.com/hntrl)! - fix tool chunk concat behavior (#9450) - [#9505](https://github.com/langchain-ai/langchainjs/pull/9505) [`138e7fb`](https://github.com/langchain-ai/langchainjs/commit/138e7fb6280705457079863bedb238b16b322032) Thanks [@chosh-dev](https://github.com/chosh-dev)! - feat: replace btoa with toBase64Url for encoding in drawMermaidImage ## 1.1.2 ### Patch Changes - [#9511](https://github.com/langchain-ai/langchainjs/pull/9511) [`833f578`](https://github.com/langchain-ai/langchainjs/commit/833f57834dc3aa64e4cfdd7499f865b2ab41462a) Thanks [@dqbd](https://github.com/dqbd)! - allow parsing more partial JSON ## 1.1.1 ### Patch Changes - [#9495](https://github.com/langchain-ai/langchainjs/pull/9495) [`636b994`](https://github.com/langchain-ai/langchainjs/commit/636b99459bf843362298866211c63a7a15c2a319) Thanks [@gsriram24](https://github.com/gsriram24)! - fix: use dynamic import for p-retry to support CommonJS environments - [#9531](https://github.com/langchain-ai/langchainjs/pull/9531) [`38f0162`](https://github.com/langchain-ai/langchainjs/commit/38f0162b7b2db2be2c3a75ae468728adcb49fdfb) Thanks [@hntrl](https://github.com/hntrl)! - add `extras` to tools ## 1.1.0 ### Minor Changes - [#9475](https://github.com/langchain-ai/langchainjs/pull/9475) [`708d360`](https://github.com/langchain-ai/langchainjs/commit/708d360df1869def7e4caaa5995d6e907bbf54cd) Thanks [@christian-bromann](https://github.com/christian-bromann)! - allow to concat system messages ### Patch Changes - [#9416](https://github.com/langchain-ai/langchainjs/pull/9416) [`0fe9beb`](https://github.com/langchain-ai/langchainjs/commit/0fe9bebee6710f719e47f913eec1ec4f638e4de4) Thanks [@hntrl](https://github.com/hntrl)! - fix 'moduleResultion: "node"' compatibility - [#9463](https://github.com/langchain-ai/langchainjs/pull/9463) [`10fa2af`](https://github.com/langchain-ai/langchainjs/commit/10fa2afec0b81efd3467e61b59ba5c82e1043de5) Thanks [@christian-bromann](https://github.com/christian-bromann)! - fix(core): update p-retry to fix memory leak ## 1.0.6 ### Patch Changes - [#9431](https://github.com/langchain-ai/langchainjs/pull/9431) [`5709cb6`](https://github.com/langchain-ai/langchainjs/commit/5709cb64cc3e4eb300bde5ec8ae90686d2aa3d8e) Thanks [@dqbd](https://github.com/dqbd)! - fix(core): `store` should be accessible from tools ## 1.0.5 ### Patch Changes - [#9308](https://github.com/langchain-ai/langchainjs/pull/9308) [`04bd55c`](https://github.com/langchain-ai/langchainjs/commit/04bd55c63d8a0cb56f85da0b61a6bd6169b383f3) Thanks [@ro0sterjam](https://github.com/ro0sterjam)! - respect JSON schema references in interopZodTransformInputSchema - [#9387](https://github.com/langchain-ai/langchainjs/pull/9387) [`ac0d4fe`](https://github.com/langchain-ai/langchainjs/commit/ac0d4fe3807e05eb2185ae8a36da69498e6163d4) Thanks [@hntrl](https://github.com/hntrl)! - Add `ModelProfile` and `.profile` properties to ChatModel ## 1.0.4 ### Patch Changes - 8319201: Export standard converter function utility ## 1.0.3 ### Patch Changes - 0a8a23b: feat(@langchain/core): support of ToolRuntime ## 1.0.2 ### Patch Changes - 6426eb6: fix chunks constructed with tool calls + chunks - 619ae64: Add `BaseMessage.toFormattedString()` ## 1.0.1 ### Patch changes - cacc137: remove bad import map exports ## 1.0.0 πŸŽ‰ **LangChain v1.0** is here! This release provides a focused, production-ready foundation for building agents with significant improvements to the core abstractions and APIs. See the [release notes](https://docs.langchain.com/oss/javascript/releases/langchain-v1) for more details. ### ✨ Major Features #### Standard content blocks A new unified API for accessing modern LLM features across all providers: - **New `contentBlocks` property**: Provides provider-agnostic access to reasoning traces, citations, built-in tools (web search, code interpreters, etc.), and other advanced LLM features - **Type-safe**: Full TypeScript support with type hints for all content block types - **Backward compatible**: Content blocks can be loaded lazily with no breaking changes to existing code Example: ```typescript const response = await model.invoke([ { role: "user", content: "What is the weather in Tokyo?" }, ]); // Access structured content blocks for (const block of response.contentBlocks) { if (block.type === "thinking") { console.log("Model reasoning:", block.thinking); } else if (block.type === "text") { console.log("Response:", block.text); } } ``` For more information, see our guide on [content blocks](https://docs.langchain.com/oss/javascript/langchain/messages#content). #### Enhanced Message API Improvements to the core message types: - **Structured content**: Better support for multimodal content with the new content blocks API - **Provider compatibility**: Consistent message format across all LLM providers - **Rich metadata**: Enhanced metadata support for tracking message provenance and transformations ### πŸ”§ Improvements - **Better structured output generation**: Core abstractions for generating structured outputs in the main agent loop - **Improved type safety**: Enhanced TypeScript definitions across all core abstractions - **Performance optimizations**: Reduced overhead in message processing and runnable composition - **Better error handling**: More informative error messages and better error recovery ### πŸ“¦ Package Changes The `@langchain/core` package remains focused on essential abstractions: - Core message types and content blocks - Base runnable abstractions - Tool definitions and schemas - Middleware infrastructure - Callback system - Output parsers - Prompt templates ### πŸ”„ Migration Notes **Backward Compatibility**: This release maintains backward compatibility with existing code. Content blocks are loaded lazily, so no changes are required to existing applications. **New Features**: To take advantage of new features like content blocks and middleware: 1. Update to `@langchain/core@next`: ```bash npm install @langchain/core@1.0.0 ``` 2. Use the new `contentBlocks` property to access rich content: ```typescript const response = await model.invoke(messages); console.log(response.contentBlocks); // New API console.log(response.content); // Legacy API still works ``` 3. For middleware and `createAgent`, install `langchain@next`: ```bash npm install langchain@1.0.0 @langchain/core@1.0.0 ``` ### πŸ“š Additional Resources - [LangChain 1.0 Announcement](https://blog.langchain.com/langchain-langchain-1-0-alpha-releases/) - [Migration Guide](https://docs.langchain.com/oss/javascript/migrate/langchain-v1) - [Content Blocks Documentation](https://docs.langchain.com/oss/javascript/langchain/messages#content) - [Agents Documentation](https://docs.langchain.com/oss/javascript/langchain/agents) --- ## 0.3.79 ### Patch Changes - 1063b43: fix chunks constructed with tool calls + chunks ## 0.3.78 ### Patch Changes - 1519a97: update chunk concat logic to match on missing ID fields - 079e11d: omit tool call chunks without tool call id ## 0.3.76 ### Patch Changes - 41bd944: support base64 embeddings format - e90bc0a: fix(core): prevent tool call chunks from merging incorrectly in AIMes… - 3a99a40: Fix deserialization of RemoveMessage if represented as a plain object - 58e9522: make mustache prompt with nested object working correctly - e44dc1b: handle backticks in structured output ## 0.3.75 ### Patch Changes - d6d841f: fix(core): Fix deep nesting of runnables within traceables ## 0.3.74 ### Patch Changes - 4e53005: fix(core): Always inherit parent run id onto callback manager from context ## 0.3.73 ### Patch Changes - a5a2e10: add root export to satisfy bundler requirements