Alternatives
Products that do what HarnessRouter: Unified interface for agent harnesses does
Hey HN! We are building HarnessRouter, a canonical API for running Codex, Claude Code, Hermes, and other managed agent harnesses as your product backend. Before building HarnessRouter, I used to build our own agent harness for our products. I tried LangGraph, agent SDKs from different vendors, pydantic, LLM tool use / function call, and so on. It's a very heavy lifting engineering effort, and I am disappointed about the agent deliveries compared to what Codex, CC can deliver. That changed my mindset. The frontier labs and famous open source communities are already putting so much…
- 1

Open-source unified interface for agent harnesses
21d ago · harnessrouter.ai
- 2
HarnessRouter▲238Bring the world's best AI agents into your app, with one API
Jul 2026 · harnessrouter.ai
- 3SM
We built a model router that plugs into coding agents (e.g. Claude Code, Codex, Cursor, etc.) and intelligently sends requests to the best model to serve them. Here's a quick demo of running it locally: https://www.youtube.com/watch?v=isKhAyivtfM. At Weave, we write most of our code with AI, and it's been getting more expensive. This came to a head when Opus 4.7 was released and, thanks to its tokenizer changes, our costs shot up. We knew we didn't need Opus for everything but we didn't want to lose out on the intelligence for the cases where you really need it. So we decided…
Jun 2026 · github.com
- 4

- 5

- 6

- 7

- 8IB
Hey HN. I built an AI agent harness over the past few months and I'm open sourcing it today. Some context on why. I've been building with Claude Code daily using this harness. It orchestrates multiple AI agents as a team, with a dashboard, chat, kanban board, the works. I used it to build a full SaaS product (MyUpMonitor, https://myupmonitor.com) in about 24 hours of focused coding. Then yesterday Anthropic announced Mythos and decided to keep it behind closed doors. Meanwhile I'm paying for Claude and I can't access their best model. I don't think that is nice at all... So I'm…
Apr 2026 · github.com
- 9

- 10

- 11PA
Hey HN. http://peerd.ai is an AI agent harness that lives entirely in your browser as a web extension. You don’t have to install a separate “AI browser”. You don’t have to bolt on or run some external process or manage a clunky mcp integration. It’s just a fully contained web extension, written in no build vanilla JS with minimal non-browser dependencies, using your own provider keys, and Apache 2. This isn’t just a fun hack. While it has largely been a solo side project, I genuinely believe the browser and the web could be the most natural platform for AI agents to operate safely,…
Jun 2026 · github.com
- 12AR
Hi HN. I'm the founder of Phoenix Labs (ex TikTok, Applied AI) and we're open sourcing our internal tooling today which is like a toolchain / meta-harness for CLI agents useful for really scaling eng and creative work. We are a very small team who's building a very ambitious product so we had to find ways to squeeze every ounce of efficiency that we could get our hands on. Harness strengths of different models (Claude, GPTs) and CLI-harnesses (Claude Code, Codex), safe/robust browser integration to speed up UX/QA testing, teams cli to speed up security reviews and parallelize…
May 2026 · agents-cli.sh
- 13

- 14OA
I've been running Claude Code and Codex together every day. At some point I figured out you can use tmux to let them talk to each other, so I started doing that. Once they could coordinate, I kept adding more agents. Before long I had a whole team working together. But any time I rebooted my machine, the whole thing was gone. Not just the tabs. The way they were wired up, what each one was doing, all of it. Nothing I'd found treats your agent setup as a topology, as something with a shape you can save and bring back. So I built OpenRig, a multi-agent harness. A harness wraps a model. A "rig"…
Apr 2026 · github.com
- 15OC
Jul 2026 · github.com
- 16

13,000+ MCP servers, skills & plugins for AI coding agents
Jul 2026 · codexmarketplaces.com
- 17

Turbocharge Claude Code, Cursor, Codex, Gemini & every coding agent: faster, cheaper, with contextual understanding specific to your codebase. - trailhq/Graft
23d ago · github.com
- 18RA
Hey HN, There’s been a lot of interest recently in meta-harnesses, loops, and multi-agent orchestration. Obviously, there are already a lot of good tools: Conductor, cmux, the native Codex / Claude Code apps, etc. For my own use cases, I’ve felt that the orchestration layer tends to feel overengineered. I mostly wanted a simple local harness (i.e Pi) for running and tracking CLI agents with the ability to hop in (via tmux). Relaymux is my opinionated attempt at that. A few design principles: - The frontend is just Telegram / iMessage / CLI. If I want more visibility, I hop…
Jun 2026 · github.com
- 19

- 20

Infinite agents, infinite loops, all human controlled.
Jun 2026 · github.com
- 21HT
Hey HN, I've had a side-project that I've slowly ticked away at over the last year called Tilde. Tilde is a harness SDK platform - I've tried to take the best things of OpenClaw, Hermes & other harnesses and decompose them and make them available as cloud API building blocks. You can use Tilde to create AI agents for your use case, fast and self-host the agent's yourself. The documentation (and attached blog post) leave a lot to be desired in terms of technical documentation but hopefully the attached git repo does a good job of showcasing the API.…
Jul 2026 · trytilde.ai
- 22LH
We built this Dockerfile because we wanted a simple harness server to run our agents and get memory, durable sessions, cron scheduling, and a vault, out of the box.
May 2026 · github.com
- 23

Harness is a coding agent that traces your codebase, implements the change, and runs the checks using your own API keys or supported subscriptions.
24d ago · harness.selimsandal.com
- 24OO
One coding agent orchestrator UI for Claude and Codex, but actually feels nice. Free, open-source, MIT licensed. Why I built it: - I wanted a lightweight UI as nice as the Codex app, but without the complexity and the custom diffs on the side - I want files and diffs open straight in my editor! - And I wanted both agents - Anthropic + OpenAI — in one place How it works: - No API keys, no OAuth, no separate billing — it just uses whatever you're already logged into. So your Claude Max and ChatGPT/Codex subscriptions both work out of the box. - Talks to Claude Code via the Claude Agent…
Apr 2026 · github.com
Ranked by how close each launch is in meaning, then by votes. Refine with a description →