npx @buildinternet/releases get langchainTrace sampling is now deterministic, and per-function anonymization fails closed when the callable errors. Switched to httpx2 with httpx as a fallback, and serializes identical replicas once into a single frame.
Alpha preview of langchain.mcp — a first-party MCPAdapter that connects any MCP server (URL, stdio script, in-process FastMCP, or a built fastmcp.Client) straight to create_agent, with multi-server fan-out, per-server auth, opt-in caching, and OAuth support. Also adds optional mid-call elicitation via LangGraph interrupts, structured tool artifacts, and automatic negotiation of legacy handshake vs. modern server/discover protocols.
Run metadata now excludes password and email environment variables, preventing credential leaks. Handles 64-bit+ integers without precision loss and closes an argument-shape bypass in Anthropic MCP redaction, plus several other fixes.
Thread streams now route LangSmith traces, improving trace visibility for streaming workflows.