Claude Agent SDK
Anthropic's first-party agent SDK for building production agents on top of Claude. Native MCP support, sub-agents, tool use, and prompt caching out of the box. Routinely benchmarked alongside Strands, LangGraph, and the OpenAI Agents SDK in 2026 framework comparisons.
Anthropic API
API access to Claude model family including Claude 3.5 Sonnet, Haiku, and Opus. Excels at coding, analysis, long-context tasks, and safety-critical applications.