Helicone
Open-source LLM observability — one-line proxy install.
Helicone is open-source LLM observability — change your OpenAI base URL once and you get logs, costs, caching, and rate limits. Self-host or use their cloud.
Pros
- ✅ One-line install
- ✅ Open source
- ✅ Generous free tier
Cons
- ⚠️ Eval features less deep than Braintrust
- ⚠️ Proxy adds a hop
Use cases
observabilitycost trackingopen source
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Braintrust
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The ML experiment tracker, now with LLM eval features.
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Humanloop
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Patronus
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Automated LLM evaluation for hallucinations, safety, and quality.
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