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

# APIs & SDK

> Choose between Atlan's HTTP APIs, CLI, MCP endpoint, and current client options.

Use the HTTP APIs when your application needs direct access to Core objects,
Agents, Skills, MCP servers and tools, or observability data. Core is the
Registry-backed surface for shared resources and scope. Extensions provide the
typed resources and tools that build on that shared layer. Use MCP when an
agent host needs governed tools and live tool discovery.

For OAuth-based MCP clients, use the Streamable HTTP endpoint
[`https://agentgateway.atlan.engineering/mcp`](https://agentgateway.atlan.engineering/mcp).

<Note>
  **Preview.** Verify HTTP, CLI, and MCP workflows in your environment before
  depending on them in production automation.
</Note>

<Note>
  The generated API reference is read-only. The site cannot send requests or
  store credentials.
</Note>

<CardGroup cols={2}>
  <Card title="Authentication" icon="key" href="/developers/authentication">
    Review authentication requirements for direct HTTP API requests.
  </Card>

  <Card title="API quickstart" icon="play" href="/developers/quickstart">
    Verify your identity, visible workspaces, and Skills with a safe first read.
  </Card>

  <Card title="CLI" icon="terminal" href="/cli/overview">
    Install the CLI, work with Registry, automate Gateway calls, and inspect traces.
  </Card>

  <Card title="SDK" icon="boxes-stacked" href="/sdk/overview">
    Review the current package status and a dependency-free client example.
  </Card>

  <Card title="API overview" icon="code" href="/developers/api-reference">
    Browse the current public Registry, Skill, Agent, File, MCP, and OTLP APIs.
  </Card>

  <Card title="Cookbooks" icon="book-open" href="/developers/build-with-atlan">
    Complete common Skill, MCP, Agent, and coding-harness tasks.
  </Card>

  <Card title="Errors and retries" icon="triangle-exclamation" href="/developers/errors-and-retries">
    Handle documented failures without guessing whether a write succeeded.
  </Card>
</CardGroup>

## Pick the smallest surface

* Start with Core for Registry-backed identity, workspaces, projects, artifacts,
  events, relationships, and search.
* Use Agents or Skills when you need their typed schemas and lifecycle routes.
* Use Files for upload destinations and version-pinned content.
* Use Observability to ingest OTLP logs, metrics, or traces.
* Use MCP when the caller needs tools from a compatible agent host.

## Automation and agents

Give a coding agent the machine-readable interface first: the public OpenAPI
document for HTTP, or `atlanai --map json` for the CLI. Require a read-only
identity check before it writes, select structured fields before it parses a
response, and keep confirmation safeguards on destructive operations.

The OpenAPI reference and command map describe the released contract. The
installed CLI and the API response remain authoritative at runtime.