Arize Phoenix vs LangWatch
An independent, evidence-based trust comparison of Arize Phoenix and LangWatch, two Observability & Evaluation projects in the HVTracker registry. Scores come from public, checkable signals — supply-chain provenance, OSSF Scorecard, maintenance, and adoption — not popularity.
LangWatch leads on trust — 83.2/100 (Grade A) vs 74.5/100 (Grade B), a 8.7-point gap. Full breakdown below.
| Signal | Arize PhoenixArize-AI/phoenix | LangWatchlangwatch/langwatch |
|---|---|---|
| HVTrust score | 74.5 | 83.2 |
| Evidence grade | B | A |
| Coverage grade | A | A |
| Overall rank | #238 | #105 |
| Rank in Observability & Evaluation | #9 | #5 |
| GitHub stars | 11.5k | 4.8k |
| Last updated | today | today |
| Build provenance | Yes | Yes |
| OSSF Scorecard | — | 4.9 / 10 |
| License | NOASSERTION | Apache-2.0 |
| Downloads | 160k/wk | 78k/wk |
| Trust dimensions (points earned) | ||
| Safety / integrity / 25 | 10.1 | 18.0 |
| Identity & provenance / 18 | 18.0 | 18.0 |
| Transparency / 17 | 8.5 | 12.7 |
| Maintenance / 20 | 20.0 | 20.0 |
| Adoption / 20 | 16.7 | 15.4 |
| Runtime capability surface (full matrix) | ||
| MCP server | Implemented | Implemented |
| External providers | 6 — Amazon Bedrock, Anthropic, E2B, … | 6 — Amazon Bedrock, Anthropic, ElevenLabs, … |
| Requires API keys | No | Yes |
| Plugin surface | plugins | plugins |
| Provenance drift | Partial | Partial |
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Arize Phoenix profile
LangWatch profile
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How to read this: HVTrust (0–100) weighs supply-chain signals (provenance, OSSF Scorecard, signed commits, open license) alongside real-world adoption, scaled by an evidence-confidence factor. Grade bands: A ≥ 80, B ≥ 65, C ≥ 50, D < 50. Signals refresh daily. Full methodology v4.3 →