You’re using Claude for coding. What about the other 99 use cases? Claude, Codex, Cursor, and Grok can’t ship tailored AI agents for every use case. They also come at a cost. Open-source harnesses, on the other hand, are free and offer unlimited customization. Here are 5 worth exploring, along with their strengths, weaknesses, and use cases 👇

You probably don't need Opus 5.5. At least for 90% of your tasks. As models get more intelligent, the gap between what frontier models can do and what cheaper, open-weight models can do is shrinking. Unless you're a developer building advanced software, there's probably no need to use Opus 5.5, Gemini 4 Argon, or GPT Astra. They're all great models, but tokenmaxxing isn't always the answer, especially when you want to run your agents 24/7 across multiple tasks. That's why we often advise our clients to use @OpenRouter to connect their custom agents to models like DeepSeek v4.1 Flash or Claude Haiku 5.5. These models are not only much faster, but also up to 40 times cheaper!

Don't build from scratch. A custom agent takes days, not weeks. We use existing open-source harnesses to ship faster: > Pi Agent. > OpenClaw. > Hermes Agent. Next time, think twice before hiring an AI Engineer. With a one-time setup, you get a tailored AI agent in a few days.

10+ API keys for your AI agent? Use one. A custom AI agent may require multiple tools: text generation, image generation, video generation, audio generation, web search, and so on. One common mistake is getting a different API key for each one. Not only do you need to create an account with each provider, but you also have to manage multiple API keys, making sure you don't lose them and that auto top-ups are enabled. Using a single inference provider, like @OpenRouter, makes the job easier. Of course, OpenRouter won't cover everything. You may still need to connect MCPs and other APIs that it doesn't provide. But it helps minimize the number of keys your agent (and you) need to manage. That's why we often recommend it to our clients. Not because we're affiliates, but because it saves them time and headaches while making onboarding much faster.