> ## Documentation Index
> Fetch the complete documentation index at: https://docs.custral.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Developer Overview

> Build on Custral: the REST API, the official SDKs, the CLI, and MCP.

Everything you build on Custral goes through **`/v1`**, one versioned, key-authenticated surface at `https://api.custral.com`. The SDKs, the CLI, and the MCP server are all clients of it, so anything they can do, you can do with `curl`.

<CardGroup cols={2}>
  <Card title="Get your first key" icon="key" href="/dev/api-reference/applications">
    Create an application and mint a scoped API key. Start here.
  </Card>

  <Card title="API Reference" icon="code" href="/dev/api-reference/overview">
    Auth, errors, and every endpoint with copy-pasteable curl.
  </Card>
</CardGroup>

***

## Pick your surface

<CardGroup cols={2}>
  <Card title="TypeScript SDK" icon="js" href="/dev/sdks/typescript">
    `@custral/sdk`. Typed access to records, objects, and ingest from Node.
  </Card>

  <Card title="Browser SDK" icon="globe" href="/dev/sdks/browser">
    `@custral/js`, the usage client and error types, for publishable keys.
  </Card>

  <Card title="React SDK" icon="react" href="/dev/sdks/react">
    `@custral/widget`: the chat widget as a component, or its headless engine.
  </Card>

  <Card title="CLI" icon="terminal" href="/dev/cli/overview">
    `@custral/cli`: sign in, switch orgs, and hit any endpoint from a shell.
  </Card>

  <Card title="MCP" icon="plug" href="/dev/mcp/overview">
    Point Claude or Cursor at your workspace and let the model read your data.
  </Card>
</CardGroup>

***

## Core concepts

<CardGroup cols={3}>
  <Card title="Authentication" icon="lock" href="/dev/auth/overview">
    Secret vs publishable keys, and the scope model.
  </Card>

  <Card title="How the schema works" icon="sitemap" href="/dev/api-reference/schema">
    Objects, properties, records, and fields: the model everything else uses.
  </Card>

  <Card title="Errors" icon="triangle-exclamation" href="/dev/errors/overview">
    The response envelope and the full error-code catalog.
  </Card>
</CardGroup>

***

## Push and receive data

<CardGroup cols={3}>
  <Card title="Create records" icon="arrow-right-to-bracket" href="/dev/api-reference/records">
    Push records in from a plain `{property: value}` map.
  </Card>

  <Card title="Webhooks" icon="webhook" href="/dev/webhooks/overview">
    Get notified when things change in your workspace.
  </Card>

  <Card title="Real-time" icon="bolt" href="/dev/realtime/overview">
    React to changes in a workspace as they happen.
  </Card>
</CardGroup>

<Info>Building something and missing an endpoint? [Tell us](mailto:hello@custral.com), the `/v1` surface grows from what people actually need.</Info>


## Related topics

- [Overview](/data/properties/common/overview.md)