LangChain

LangChain builds the agent engineering platform and open source frameworks developers need to ship reliable AI agents faster. LangSmith, the commercial platform, covers the full agent development lifecycle — from tracing and debugging to evaluation, deployment, and no-code agent building. The open source ecosystem includes LangChain for quick-start agents, LangGraph for production-grade agents with low-level control, and deepagents for long-running autonomous tasks.

• LangSmith Observability — Trace every agent execution with a structured timeline of steps; supports native tracing for popular frameworks and OpenTelemetry, plus SDKs for Python, TypeScript, Go, and Java.
• LangSmith Evaluation — Capture production traces, convert them into test cases, and score agents using LLM-as-judge, multi-turn evals, human feedback annotations, and online/offline scoring.
• LangSmith Deployment — Ship agents with built-in memory, conversational threads, durable checkpointing, human-in-the-loop support, type-safe streaming, and native A2A & MCP protocol support.
• LangSmith Fleet — Build no-code agents for daily tasks using plain language; supports prebuilt templates, remote MCP server tools, bring-your-own models, and integrated LangSmith tracing.
• LangGraph — Open source framework for building reliable, production-grade agents with fine-grained control over state, branching logic, and multi-agent orchestration.
• LangChain (framework) — Open source batteries-included framework for quickly building agents with any model provider using templates and integrations.
• deepagents — Open source framework for highly autonomous, long-running agents capable of planning, using subagents, and leveraging file systems for complex tasks.
• Prompt Hub & Playground — Manage, test, and auto-improve prompts; Canvas provides an interface for iterative prompt refinement.
• Annotation Queues — Collect structured human feedback on agent outputs to calibrate automated evaluators and improve model quality.
• Enterprise Hosting Options — Choose cloud, hybrid (SaaS control plane + self-hosted data plane), or fully self-hosted deployments to keep data within your VPC.