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

# Build with Interchange

> Connect agents and applications to Interchange with MCP or REST.

Build buyer agents, seller integrations, automations, and reporting systems on
the same Interchange platform. Start with the stable v2 API unless Scope3 has
enrolled your account in the v3 preview.

<CardGroup cols={2}>
  <Card title="Connect an AI agent" icon="message-bot" href="/v2/quickstart">
    Connect Claude, ChatGPT, Cursor, or another MCP client in a few minutes.
  </Card>

  <Card title="Authenticate" icon="key" href="/v2/authentication">
    Choose OAuth for interactive agents or an organization API key for
    automation.
  </Card>

  <Card title="Build a buyer integration" icon="user" href="/v2/buyer-api-reference">
    Create advertisers and campaigns, discover products, and read delivery.
  </Card>

  <Card title="Build a seller integration" icon="store" href="/v2/storefront-api-reference">
    Configure a Seller Account, connect inventory sources, and operate demand.
  </Card>
</CardGroup>

## Choose an API version

Use the version picker in this section to move between API generations:

* **v2 — Stable:** the default production API, with MCP and REST surfaces for
  buyer and seller integrations.
* **v3 — Preview:** one account-resolved MCP endpoint with typed, noun-shaped
  tools. It is available only to enrolled accounts and is not yet a replacement
  for every v2 workflow.

<Note>
  Selecting v3 changes the developer documentation shown in this section. It
  does not change your account, migrate an integration, or enroll you in the
  preview.
</Note>

Read the [v3 preview guide](/v2/setup/v3-preview) for availability, connection
details, supported account kinds, and current limitations.