langchain-ai/langchainjs langchain==1.0.0-alpha.7 on GitHub

🚀 New Features

Todo Middleware (#9051): Added new todo middleware functionality for agent workflows
LLM Tool Selector Middleware (#9050): Implemented llmToolSelectorMiddleware (bigTool) for intelligent tool selection
Middleware Tool Definition (#9046): Middleware can now define their own tools dynamically
Dynamic Prompt Middleware (#8993): Added built-in middleware for dynamic prompt generation
Unsupported Model Behavior (#9039): Added unsupportedModelBehavior property to anthropic middleware

System Prompt Consistency (#9045): Fixed system prompt handling across all agent components
Zod Interoperability (#9029): Improved compatibility between Zod v3 and v4
Structured Output Handling (#9033): Improved structured output processing for agents
Graph Support for Jumps (#9035): Added statically typed graph support for agent jumps
Tool Configuration Naming (#9034): Renamed toolConfigs to interruptOn for clarity
LLM Property Removal (#9017): Removed llm prop from middleware agent
Message Handling: Fixed grabbing last AIMessage from list instead of just looking at last message
Memory Saver Export (#8996): Removed incorrect MemorySaver re-export
Middleware Naming (#8912): Fixed "middlewares" property naming to "middleware"
Cache Control Verification: Actually verify cache control values in usage response
Message Instance Checking (#8905): Use isInstance for message validation

OpenAI Provider Dependency (#8920): Removed dependency to openai provider package (alpha.6)
Internal ESLint Package (#8770): Created internal ESLint package (alpha.6)
Zod v4 Support (#8792): Updated to support Zod v4 (alpha.6)
Test Console Logs (#8998): Removed console logs in test files (alpha.7)