$ find your agent harness

A curated, verified, cross-vendor directory of AI agent harnesses — the runtime scaffolding that turns a model into an agent.

◆ 74 harnesses profiled · 9-axis capability schema · last verified 2026-07-08

1 of 74 harnesses · sorted by stars

Claude Agent SDK · Anthropic

★ 7,560 · high

Anthropic's production agent library exposing the same harness that powers Claude Code (tool loop, file/bash/web tools, subagents, hooks, skills, MCP, permission checkpoints) in Python and TypeScript; the MIT-licensed SDK wraps the bundled Claude Code runtime and, as of 2026, underpins Anthropic Managed Agents with separate metered billing from June 15, 2026.

Runtimes & SDKsopen-sourceusage-based✓ mcp✓ skills⛨ optional