$ 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

OpenAI Agents SDK · OpenAI

★ 27,727 · high

OpenAI's agent harness whose April 15, 2026 overhaul added a 'model-native harness' with Codex-like filesystem/shell tools, built-in compaction and memory, snapshot/rehydrate durable execution, handoffs, guardrails, tracing, and native sandbox execution via bring-your-own or built-in providers (E2B, Modal, Daytona, Cloudflare, Vercel, Blaxel, Runloop); non-OpenAI models supported via LiteLLM and Chat Completions-compatible endpoints.

Runtimes & SDKsopen-sourceusage-based✓ mcp✓ local models⛨ optional