Comparison
Nexus vs Confident AI for Agent Observability
Confident AI is the cloud platform built by the DeepEval team — the creators of the most popular open-source LLM testing library. It focuses on LLM evaluation, regression testing, and dataset management. Nexus focuses on production runtime observability. Here's when each tool is the right fit.
TL;DR
Choose Nexus if you…
- ✓ Running AI agents in production and need runtime trace visibility
- ✓ Want per-agent health cards, error rates, and alerting
- ✓ Need webhook and email alerts when agent error rates spike
- ✓ Want a managed platform at $9/mo flat — no evaluation quotas
Choose Confident AI if you…
- ✓ Already using DeepEval and want a managed cloud backend
- ✓ Need LLM regression testing across prompt or model versions
- ✓ Building curated evaluation datasets with human annotation
- ✓ Your primary concern is LLM output quality, not runtime health
Feature Comparison
| Feature | Nexus | Confident AI |
|---|---|---|
| Primary focus | Agent runtime observability | LLM evaluation and regression testing |
| Live agent tracing | ✓ Full span waterfall, per-agent view | Offline test runs, not live runtime traces |
| LLM regression testing | Not supported | ✓ Core feature — compare across versions |
| Evaluation datasets | ✗ Not supported | ✓ Dataset management with human annotation |
| Per-agent health dashboard | ✓ Error rates, 7d trends, alerting | No agent-level health view |
| Webhook / email alerts | ✓ Included on Pro plan | Not available |
| DeepEval integration | Not built-in | ✓ Native — built by the DeepEval team |
| Multi-framework support | ✓ LangChain, CrewAI, AG2, LangGraph, more | ✓ Works with any Python LLM framework |
| Setup time | 5 min — one API call to start tracing | Requires DeepEval test suite setup |
| Pricing | Free tier + $9/mo flat (Pro) | Free OSS DeepEval + paid Confident AI cloud |
The honest take
Confident AI and Nexus solve different problems. Confident AI is the managed cloud layer on top of DeepEval — if you're already using DeepEval to unit-test your LLM pipelines, Confident AI gives you a dashboard to track test results, manage evaluation datasets, and run regression suites when you change prompts or swap models. It's pre-production quality tooling.
Nexus is post-deployment monitoring. Once your agent is live, you need to know which production runs failed, how long tools took to execute, and which agents have elevated error rates right now. That's real-time span tracing, per-agent health cards, and webhook alerts — not eval dataset management.
DeepEval is genuinely excellent (~5K GitHub stars) and Confident AI is the natural cloud home for teams who already write DeepEval test cases. If LLM output quality and regression testing are your priority, Confident AI is a strong choice.
Many teams use both in sequence: DeepEval + Confident AI in CI to gate quality before deploy, Nexus in production to monitor runtime health after deploy. If you're only choosing one and your question is “are my production agents healthy right now?” rather than “do my LLM outputs meet quality thresholds?” — Nexus is the answer.
Try Nexus free
Managed agent observability. Free tier, no credit card required. Works with LangChain, CrewAI, AG2, LangGraph, and more.