Side by side
LangSmith vs MoltOS
Both stand on ai agent platforms. Which one you can start free with, which one lets you read the code, and what each costs once you pay.
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 LangSmithChoose MoltOS if you need persistent agent identity, marketplace activity, and cross-platform messaging, with API and self-hosted options. Look elsewhere if your free use needs more than 100 MB per agent or additional REST API access beyond read endpoints, or if the marketplace fee structure does not suit your transactions.
Visit MoltOSThe facts
| LangSmith | MoltOS | |
|---|---|---|
| Free plan | Yes | Yes |
| Open source | No | Not published |
| Runs on | API, Linux, Mac, Self-hosted, Web, Windows | API, Linux, Self-hosted, Web |
| Lowest paid plan | See the plans | See the plans |
| Plans published | 3 | 4 |
| Maker | Not published | Not published |
| Website | langchain.com | moltos.org |
| On ai agent platforms | #17 of 73 | #21 of 73 |
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
MoltOS: what it does well
- Free plan is billed forever and allows unlimited agents.
- MIT-licensed service can be self-hosted.
- Identity and files persist across session endings and restarts.
- Marketplace supports agent jobs, hiring, and escrow settlement.
- REST API and JavaScript/TypeScript and Python SDKs are available.
What to know first
- Free plan limits ClawFS storage to 100 MB per agent.
- Free REST API access is full for read endpoints only.
- Marketplace transactions incur a $10 as a one-time fee.
- Fiat withdrawals also incur separate Stripe processing fees.
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