Arthur Engine
Open-source engine for LLM guardrails, trace-based evaluation and prompt management that you can run on your own infrastructure.
By Arthur · www.arthur.ai
Package download activity
Arthur Engine has no PyPI or npm package that maps to it (SDK not mapped (its registry metadata does not link the vendor's domain or GitHub organisation)). This is not a zero.
Packages not measured
The vendor's docs name these packages, but their registry metadata does not link the vendor's domain or GitHub organisation, so under our mapping rule they are not counted. No download number is shown for them.
- PyPI
arthur-observability-sdk: registry metadata has no project/repository/homepage link (registry metadata, checked 2026-10-07)
GitHub stars
arthur-ai/arthur-engine: 91 stars (rank 38). Stars are a point-in-time count of a repository's bookmarks, not people using the tool.
Series starts 2026-W40 (91).
Facts
| Categories | Guardrails & safety, Evaluation, Tracing & observability, Prompt management | |
|---|---|---|
| Status | Generally available | |
| Licence | MIT (open core) | source, checked 2026-10-07 |
| Self-host | Yes | source, checked 2026-10-07 |
| OpenTelemetry | Native (OTLP) | source, checked 2026-10-07 |
| Pricing model | flat | |
| Entry price | $60/mo; Arthur Platform (hosted) plans: Free $0, Premium $60/mo, Enterprise custom. The open-source Arthur Engine itself is free to self-host (MIT). | source, checked 2026-10-07 |
| Free tier | Yes | |
| Measurability | SDK not mapped (its registry metadata does not link the vendor's domain or GitHub organisation) |
Facts last verified 2026-10-07 on first-party pages. Prices as published, taxes excluded; non-USD prices are not converted.
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