# Arize Phoenix vs LangSmith API + MCP (slim)

> Arize Phoenix has a score of 75.6 (BB) against LangSmith API + MCP's 71.3 (BB). Both do obs traces. The largest gap is security & auth, 21 points. Category scores, facts, verdicts and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/arize-phoenix-vs-langsmith.md (~1,600 tokens) · this version ~330 tokens · JSON https://www.anchorterminal.com/compare/arize-phoenix-vs-langsmith.json · canonical https://www.anchorterminal.com/compare/arize-phoenix-vs-langsmith
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-05

Arize Phoenix has a score of 75.6 (BB) against LangSmith API + MCP's 71.3 (BB). Both do obs traces. The largest gap is security & auth, 21 points.

- Arize Phoenix: BB 75.6, rank #32 of 452 · https://www.anchorterminal.com/tools/arize-phoenix.min.md
- LangSmith API + MCP: BB 71.3, rank #85 of 452 · https://www.anchorterminal.com/tools/langsmith.min.md
- Pick Arize Phoenix for agent ergonomics (+14), payments & pricing (+20). Pick LangSmith API + MCP for security & auth (+21).

| Category | Arize Phoenix | LangSmith API + MCP |
| --- | --- | --- |
| Reliability (16%) | 77 | 81 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 88 | 86 |
| Agent ergonomics (13%) | 90 | 76 |
| Security & auth (14%) | 56 | 77 |
| Payments & pricing (10%) | 60 | 40 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 84 | 85 |
| Transparency & trust (7%) | 76 | 78 |