#66th of 38 in Agent and MCP starters

penguin-harness

Agent framework that evolves an agent's prompts, skills and tools against benchmarks

Stars
2.9k
License
Apache-2.0
Last commit
Oct 2026
Last release
Oct 2026
Language
TypeScript
Stars, last 14 weeks+2,892
14 Jul 2026: 3 stars21 Jul 2026: 114 stars28 Jul 2026: 206 stars4 Aug 2026: 542 stars11 Aug 2026: 1,166 stars18 Aug 2026: 1,486 stars25 Aug 2026: 1,660 stars1 Sept 2026: 1,885 stars8 Sept 2026: 2,020 stars15 Sept 2026: 2,188 stars22 Sept 2026: 2,331 stars29 Sept 2026: 2,413 stars6 Oct 2026: 2,440 stars13 Oct 2026: 2,506 stars20 Oct 2026: 2,895 stars

3 on 14 Jul 20262,895 on 20 Oct 2026

From GitHub's daily star counts.

Checked on GitHub.

Overview

PenguinHarness runs agents with a small toolset and keeps the model fixed while it evolves the harness (prompts, Skills, tools, hooks) over scored rounds. Five RSI algorithms (default, OPRO, APE, ACE, AWM) ship as plugins and run on built-in Harbor benchmarks in Docker, with each candidate snapshotted as a version. It ships as a desktop app, Web App, CLI and TypeScript SDK, and can also generate agent apps from a prompt.

Who it is for: Engineers tuning agent prompts and skills, or self-hosting agents

Strengths

  • Five RSI algorithms run on the same benchmarks, scoreboard and per-version snapshots
  • Desktop app, Web App, CLI and SDK share one engine and the ~/.penguin/data directory
  • Works with many providers plus custom OpenAI-protocol endpoints, including local models
  • Agents can run on remote machines over ssh and drive Chrome through an extension

Weaknesses

  • Benchmarks run as Harbor tasks in Docker, so self-evolution needs Docker
  • Cost and accuracy claims come from the project's own suite, not independent runs
  • RAM and disk requirements are not documented
  • Company-level self-evolution and OpenShell integration are still unchecked roadmap items

What it needs

  • TypeScript, OpenAI, Anthropic, Google Gemini, OpenRouter
  • Needs Node >= 24 (npm install), Docker (benchmarks), Model provider API key
  • Docker
  • env example file

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