An independent, evidence-based trust comparison of Arize Phoenix and MLflow, two Observability & Evaluation projects in the HVTracker registry. Scores come from public, checkable signals — supply-chain provenance, OSSF Scorecard, maintenance, and adoption — not popularity.
| Signal | Arize PhoenixArize-AI/phoenix | MLflowmlflow/mlflow |
|---|---|---|
| HVTrust score | 77.3 | 88.2 |
| Evidence grade | B | A |
| Coverage grade | A | A |
| Overall rank | #49 | #13 |
| Rank in Observability & Evaluation | #3 | #1 |
| GitHub stars | 10.5k | 27.0k |
| Last updated | today | 1d ago |
| Build provenance | Yes | Yes |
| OSSF Scorecard | — | 5.5 / 10 |
| License | NOASSERTION | Apache-2.0 |
| Downloads | 469k/wk | 8.8M/wk |
| Trust dimensions (points earned) | ||
| Safety / integrity / 25 | 12.5 | 19.4 |
| Identity & provenance / 20 | 18.0 | 18.0 |
| Transparency / 17 | 8.5 | 13.2 |
| Maintenance / 20 | 20.0 | 19.9 |
| Adoption / 20 | 17.2 | 19.9 |
| Runtime capability surface (full matrix) | ||
| MCP server | Implemented | Implemented |
| External providers | 5 — Amazon Bedrock, Anthropic, E2B, … | 5 — Amazon Bedrock, Anthropic, Google Gemini, … |
| Requires API keys | No | No |
| Plugin surface | plugins | plugins |
| Provenance drift | Partial | Unknown |
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 v4.2 →