> ## Documentation Index
> Fetch the complete documentation index at: https://langchain-5e9cc07a-preview-docsby-1791319236-3be7a15.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Set up LangSmith

> Host and manage LangSmith infrastructure for observability, evaluation, and prompt engineering.

Set up **LangSmith** for [observability](/langsmith/observability), [evaluation](/langsmith/evaluation), and [prompt engineering](/langsmith/prompt-context-hub#prompts). LangSmith offers Cloud, Bring Your Own Cloud (BYOC), and Self-hosted options. Choose the option that matches where your data has to live and who runs the infrastructure.

<Note>
  If you also want to deploy agents in production, you can use [**LangSmith Deployment**](/langsmith/deployment) with Cloud, BYOC, or Self-hosted.
</Note>

<CardGroup cols={3}>
  <Card title="Cloud" cta="Get started" href="/langsmith/cloud" icon="cloud">
    Fully managed observability, evaluation, and prompt engineering.
  </Card>

  <Card title="BYOC" cta="Learn about BYOC" href="/langsmith/byoc" icon="cloud-cog">
    Full control over your data, while LangChain manages the infrastructure.
  </Card>

  <Card title="Self-hosted" cta="Run self-hosted" href="/langsmith/self-hosted" icon="server">
    Full control with observability, evaluation, and prompt engineering in your infrastructure.
  </Card>
</CardGroup>

<Callout>
  Self-hosted and BYOC are available on the [Enterprise plan](/langsmith/pricing-plans). [Get a demo](https://www.langchain.com/contact-sales) to learn more.
</Callout>

## Compare Cloud, BYOC, and Self-hosted

| Feature | **Cloud** | **BYOC** | **Self-hosted** |
| - | - | - | - |
| **Who runs the infrastructure** | LangChain | LangChain runs the control plane, you run your data planes | You |
| **Where sensitive data lives** | LangChain's cloud | Your VPC | Your VPC |
| **Upgrades and patches** | Automatic | Automatic | Manual |
| **Scaling** | Automatic | Automatic, managed by LangChain | Manual |

Cloud, BYOC, and Self-hosted support [LangSmith Deployment](/langsmith/deployment) for agent workloads. Refer to the [LangSmith Deployment overview](/langsmith/deployment) to pick a topology (Cloud managed, BYOC, Hybrid, self-hosted with control plane, or standalone).

## Common setups

* **Fastest to start, managed everything.** [LangSmith Cloud](/langsmith/cloud) paired with [LangSmith Deployment](/langsmith/deployment) on Cloud. LangChain hosts the platform, and, when you use LangSmith Deployment, also hosts your [Agent Servers](/langsmith/agent-server).
* **Bring Your Own Cloud.** Data stays in your VPC, and LangChain manages the infrastructure. Refer to the [BYOC overview](/langsmith/byoc).
* **Observability data must stay in your infrastructure.** Self-hosted LangSmith, paired with any LangSmith Deployment topology, including [self-hosted LangSmith Deployment](/langsmith/deploy-with-control-plane) for agent workloads.
* **Managed observability, agents in your VPC.** LangSmith Cloud paired with [Hybrid](/langsmith/hybrid) LangSmith Deployment. Traces and evaluations stay on SaaS while agent workloads stay in your infrastructure.
* **Observability only, no agent hosting.** LangSmith Cloud or self-hosted, without LangSmith Deployment. Run your agents wherever you already run apps and send traces to LangSmith.

## Related

<CardGroup cols={3}>
  <Card title="Account setup" cta="Set up your account" href="/langsmith/admin" icon="user-cog">
    Create an account, manage API keys, and choose a pricing tier.
  </Card>

  <Card title="Plans and pricing" cta="View pricing" href="https://www.langchain.com/pricing" icon="credit-card">
    Compare LangSmith plans and tiers.
  </Card>

  <Card title="Observability" cta="Learn more" href="/langsmith/observability" icon="chart-line">
    Trace and monitor your LLM applications.
  </Card>
</CardGroup>

***

<div className="source-links">
  <Callout icon="terminal-2">
    [Connect these docs](/use-these-docs) to your agent of choice via MCP for real-time answers.
  </Callout>

  <Callout icon="edit">
    [Edit this page on GitHub](https://github.com/langchain-ai/docs/edit/main/src/langsmith/platform-setup.mdx) or [file an issue](https://github.com/langchain-ai/docs/issues/new/choose).
  </Callout>
</div>