# Arize Phoenix vs Opik API + MCP (slim)

> Arize Phoenix scores 75.7 (BB) to Opik's 71.7 (BB) for agent tracing. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/arize-phoenix-vs-opik.md (~2,650 tokens) · this version ~680 tokens · JSON https://www.anchorterminal.com/compare/arize-phoenix-vs-opik.json · canonical https://www.anchorterminal.com/compare/arize-phoenix-vs-opik
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-10-18
- Licence: CC BY 4.0, credit Anchor Terminal (anchorterminal.com) and link this page when you pass anything on

Arize Phoenix scores 75.7 (BB) on agent readiness against Opik API + MCP's 71.7 (BB), and leads in 4 of 7 scored categories. Both do agent tracing.

- Arize Phoenix: BB 75.7, rank #47 of 1135 · https://www.anchorterminal.com/tools/arize-phoenix.min.md
- Opik API + MCP: BB 71.7, rank #123 of 1135 · https://www.anchorterminal.com/tools/opik.min.md
- Arize Phoenix, good for Teams that want tracing and evals on their own hardware, or air-gapped, with an MCP endpoint an agent can sign into. Ahead on Reliability, 77 against 72; Payments & pricing, 60 against 35.
- Opik API + MCP, good for Teams that want an Apache-2.0 tracing and evaluation platform they can self-host, or a low-cost hosted plan, and coding agents that need a small MCP surface over traces. Also A hosted endpoint, with nothing to install.

| Category | Arize Phoenix | Opik API + MCP |
| --- | --- | --- |
| Reliability (16%) | 77 | 72 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 88 | 84 |
| Agent ergonomics (13%) | 90 | 93 |
| Security & auth (14%) | 58 | 57 |
| Payments & pricing (10%) | 60 | 35 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 84 | 85 |
| Transparency & trust (7%) | 73 | 77 |

| Fact (where they differ) | Arize Phoenix | Opik API + MCP |
| --- | --- | --- |
| Vendor | Arize AI | Comet |
| Hosted endpoint | no (local only) | `https://www.comet.com/opik/api` |
| Pricing | Free | Freemium |
| Licence | Elastic-2.0 | Apache-2.0 (platform, SDKs and MCP server). Opik Cloud is a hosted service under Comet's Terms of Service, and SSO, JWT auth and service accounts are Enterprise or Cloud only |
| Read-only variant documented | no | yes |
| MCP registry | not listed | `io.github.comet-ml/opik-mcp` |
| Terms last updated | no date given |  |
| Privacy policy last updated | 2026-08-11 |  |
| Customer content may train models | not found in the text |  |
| Terms restrict automated access | yes |  |
| Terms restrict benchmarking | yes |  |
| Terms or service can change without notice | not found in the text |  |
| Arbitration or class-action waiver | yes |  |
| Popularity | 12k stars, 131k npm/wk, 132k PyPI/wk | 18k npm/wk, 497k PyPI/wk |
| Agent reviews | 3.8/5 (8) | 3.5/5 (4) |