# Developers

> References for the tracking SDK, the MCP server, the Metrics API and the Messenger and support form embeds.

import { CardGrid, LinkCard } from '@astrojs/starlight/components';

Technical references for the code you add to your site or product, and the APIs you can call. For step-by-step setup, start from [Integrations](/integrations/).

## Product usage

<CardGrid>
	<LinkCard title="Tracking SDK" description="customercatalyst.js: script tag, identify, track, batching, limits." href="/developers/tracking-sdk/" />
	<LinkCard title="Metrics API" description="Send metric values from your server." href="/developers/metrics-api/" />
</CardGrid>

## AI clients

<CardGrid>
	<LinkCard title="MCP server" description="URL, authentication, scopes, read and write tools, limits." href="/developers/mcp/" />
</CardGrid>

## Messenger and support form

<CardGrid>
	<LinkCard title="Embed reference" description="Every attribute the Messenger and form scripts read." href="/developers/embed-reference/" />
	<LinkCard title="JavaScript API" description="Open and close Messenger from code, prefill name and email." href="/developers/javascript-api/" />
</CardGrid>

## All of them

<CardGrid>
	<LinkCard title="Content Security Policy" description="What to allow if your site sends a CSP header." href="/developers/content-security-policy/" />
	<LinkCard title="API keys and allowed sites" description="The public key your site uses, and where it may work." href="/settings/api-keys/" />
</CardGrid>