Side by side
LangSmith vs PetalTrace
Both stand on ai agent observability tools. Which one you can start free with, which one lets you read the code, and what each costs once you pay.
Free plan APILinuxMac+3
LangSmith combines agent evaluation with prompt tools and observability, including cost and trajectory tracking. Teams should account for trace-retention limits and the pay-as-you-go structure when comparing plans.
Visit LangSmith Free plan APILinuxMac+3
PetalTrace brings tracing, cost analysis, run comparison and replay into one developer-facing toolset. Teams considering deployment should account for authentication being disabled by default.
Visit PetalTraceThe facts
| LangSmith | PetalTrace | |
|---|---|---|
| Free plan | Yes | Yes |
| Open source | No | Not published |
| Runs on | API, Linux, Mac, Self-hosted, Web, Windows | API, Linux, Mac, Self-hosted, Web, Windows |
| Lowest paid plan | See the plans | Free or on request |
| Plans published | 3 | 1 |
| Maker | Not published | Not published |
| Website | langchain.com | docs.petallabs.io |
| On ai agent observability tools | #18 of 31 | #22 of 31 |
LangSmith: what it does well
- Offline and real-time evaluation options
- Human, heuristic, LLM, pairwise, and custom evaluators
- Tracing includes cost tracking and trajectory monitoring
- Free Developer plan with up to 5k base traces monthly
- Enterprise offers self-hosted and hybrid deployment
What to know first
- Base traces have 14-day retention
- Extended 180-day retention costs extra
- Developer includes one seat and community support
PetalTrace: what it does well
- Captures prompts, tool calls, token use and costs.
- Compares runs for content and cost differences.
- Replays runs with different models or temperatures.
- Accepts standard OpenTelemetry traces.
- The public repository identifies an MIT license.
What to know first
- Authentication is future functionality and disabled by default.
- Documented trace storage uses SQLite.
- No commercial pricing or usage limits are stated.
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