Original release notes
Changes since langchain==1.3.18
docs(langchain): runnable langchain.mcp examples (#39976) feat(langchain): langchain.mcp namespace, MCPAdapter (#39939) perf(anthropic,langchain): omit middleware trace inputs (#40098) fix(langchain): include model destination in agent tool routing (#38355) chore(langchain): bump vcrpy test dependency minimum to >=8.2.0 (#39942)
