Registry › Compare › Arize Phoenix vs LangWatch

Arize Phoenix vs LangWatch

LangWatch leads on trust: 86.7/100 (Grade A) against 75.1/100 (Grade B), a 11.6-point gap. Arize Phoenix leads on adoption; LangWatch leads on supply-chain integrity and transparency.

B Arize Phoenix 75.1

AI Observability & Evaluation

Arize-AI/phoenix · #261 overall · #9 Observability & Evaluation · coverage A (4/5)

Choose Arize Phoenix if adoption matters most.

+1.3Adoption: 158.2k weekly downloads against 83.1k

A LangWatch 86.7

Open-Source Agent Observability & Evals for AI Platform teams. Trace, test, route and govern every agent & coding assistant in the company.

langwatch/langwatch · #76 overall · #3 Observability & Evaluation · coverage A (4/5)

Choose LangWatch if supply-chain integrity and transparency matter most.

+7.0Safety / Integrity: 82% of recent commits signed, against 63%
+4.2Transparency

Where they differ

10.7

Safety / IntegrityLangWatch +7.0

17.7

8.5

TransparencyLangWatch +4.2

12.7

16.7

AdoptionArize Phoenix +1.3

15.4

+1.2

Runtime calibrationLangWatch +1.7

+2.9

2 dimensions identical: Identity 18.0 · Maintenance 20.0 · Full evidence table

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.

Full evidence

Signal	Arize PhoenixArize-AI/phoenix	LangWatchlangwatch/langwatch
HVTrust score	75.1	86.7
Evidence grade	B	A
Coverage grade	A	A
Overall rank	#261	#76
Rank in Observability & Evaluation	#9	#3
GitHub stars	12.1k	5.0k
Last updated	today	today
Build provenance	Yes	Yes
OSSF Scorecard	—	4.9 / 10
License	NOASSERTION	Apache-2.0
Downloads	158k/wk	83k/wk
Trust dimensions (points earned)
Safety / integrity / 25	10.7	17.7
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, …	1 — Anthropic
Requires API keys	No	No
Plugin surface	plugins	plugins
Provenance drift	Partial	Partial

Open in the live compare tool → Arize Phoenix profile LangWatch profile More Observability & Evaluation →

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 v4.4 →