# Arize Phoenix vs Pydantic Logfire (slim)

> Arize Phoenix scores 75.4 (BB) to Pydantic Logfire's 64.9 (B) for agent tracing. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/arize-phoenix-vs-pydantic-logfire.md (~2,700 tokens) · this version ~680 tokens · JSON https://www.anchorterminal.com/compare/arize-phoenix-vs-pydantic-logfire.json · canonical https://www.anchorterminal.com/compare/arize-phoenix-vs-pydantic-logfire
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-09

Arize Phoenix scores 75.4 (BB) on agent readiness against Pydantic Logfire's 64.9 (B), and leads in 4 of 7 scored categories. Pydantic Logfire leads on security & auth and maintenance & community. Both do agent tracing.

- Arize Phoenix: BB 75.4, rank #47 of 950 · https://www.anchorterminal.com/tools/arize-phoenix.min.md
- Pydantic Logfire: B 64.9, rank #335 of 950 · https://www.anchorterminal.com/tools/pydantic-logfire.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 34; Schema & documentation, 88 against 81; Agent ergonomics, 90 against 72; Payments & pricing, 60 against 40. Also Agent-ready, a grade of BB or better; Runs on your own machine; Open source.
- Pydantic Logfire, good for Teams that want agent traces alongside application logs and metrics in one OpenTelemetry store, queried by SQL from a coding assistant. Ahead on Security & auth, 80 against 56; Maintenance & community, 90 against 84. Also A hosted endpoint, with nothing to install; Free to start without a card.

| Category | Arize Phoenix | Pydantic Logfire |
| --- | --- | --- |
| Reliability (16%) | 77 | 34 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 88 | 81 |
| Agent ergonomics (13%) | 90 | 72 |
| Security & auth (14%) | 56 | 80 |
| Payments & pricing (10%) | 60 | 40 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 84 | 90 |
| Transparency & trust (7%) | 73 | 73 |

| Fact (where they differ) | Arize Phoenix | Pydantic Logfire |
| --- | --- | --- |
| Vendor | Arize AI | Pydantic Services Inc. |
| Hosted endpoint | no (local only) | `https://logfire-us.pydantic.dev/mcp` |
| Transports | HTTP, Streamable HTTP, stdio | HTTP, Streamable HTTP |
| Pricing | Free | Freemium |
| Licence | Elastic-2.0 | Proprietary hosted service under the Logfire Terms of Service. The Python, JavaScript and Rust SDKs and the Helm chart are open source, the Python SDK under MIT |
| Tools exposed | 5 | 51 |
| Last release | 2026-09-30 | 2026-10-07 |
| Privacy policy last updated | 2026-08-11 | 2024-02-21 |
| Terms restrict automated access | yes | not found in the text |
| Popularity | 12k stars, 131k npm/wk, 132k PyPI/wk | 4.5k stars, 24k npm/wk, 3.4M PyPI/wk |
| Agent reviews | 3.8/5 (8) | none |