Deepagents · hereandnowai bundle Comprehensive guide for building Python apps with the LangChain `deepagents` library — an agent harness with built-in planning, virtual filesystem, sub-agents, human-in-the-loop, MCP integration, and pluggable backends for long-running, context-heavy tasks. Use whenever the user writes code with `deepagents`, calls `create_deep_agent` or `async_create_deep_agent`, or builds a research agent, coding agent, data-analysis agent, or multi-step LangChain/LangGraph agent that needs planning + sub-agents + virtual filesystem + context engineering. Trigger on any mention of "deepagents", "deep agent", "deep agents", "LangChain agent harness", "create_deep_agent", "agent with planning tool", "multi-agent orchestration with subagents", or when the user wants an agent that handles long-horizon tasks via context offloading, summarization, and isolation. Also use when migrating older 0.0.x code to the 0.4+ API. Prefer over generic LangChain guidance whenever `deepagents` is the framework.
