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

# Quick start

> Connect Claude, Cursor, or another AI assistant to your Flex account in under five minutes.

<Frame>
  <img src="https://mintcdn.com/flex-87/yb73-KIB1zcv0rGg/images/mcp/mcp-hero.png?fit=max&auto=format&n=yb73-KIB1zcv0rGg&q=85&s=b02cc71792d641f981f13f7312b836b4" alt="Claude using the Flex MCP to create a product" width="1800" height="1168" data-path="images/mcp/mcp-hero.png" />
</Frame>

The Flex MCP server is hosted at `https://mcp.withflex.com`. Pick the client you use below — most paths take less than five minutes. The Claude.ai (web) flow is the most beginner-friendly; Claude Code is the best fit for developers; Cursor, Windsurf, and VS Code each have one-click install links from the [Flex MCP landing page](https://mcp.withflex.com).

## Claude.ai (per user)

Works on every paid Claude.ai plan (Pro, Max, Team, Enterprise) and only takes a sign-in.

<Steps titleSize="h3">
  <Step title="Open Claude.ai connector settings">
    Go to [claude.ai](https://claude.ai) → **Settings** → **Connectors**.
  </Step>

  <Step title="Add a custom connector">
    Click **Add custom connector**, then paste the Flex MCP URL:

    ```
    https://mcp.withflex.com/api/mcp/oauth
    ```

    Give it a name (e.g. "Flex") and click **Add**.
  </Step>

  <Step title="Sign in with your Flex account">
    Claude will open a browser window to sign in. Use the email/password (or SSO) you use for the [Flex Dashboard](https://dashboard.withflex.com). Approve the access prompt.
  </Step>

  <Step title="Try it">
    Back in Claude, ask:

    > Use the Flex MCP to list my five most recent payment intents.

    Claude will request approval to call a Flex tool the first time. Allow it once or "for this task," and you're connected.

    <Note>
      🧪 Heads up — Claude.ai is OAuth, so test vs. live mode is set **per call** via an `api_test_mode` parameter the LLM passes to each tool. By default, read tools return live data and write tools require you to specify the mode. See [Test mode](/developer-guides/integration/mcp/authentication#test-mode) for the full behavior.
    </Note>
  </Step>
</Steps>

## Claude.ai (workspace admin)

If you're on a **Team or Enterprise** plan, an admin can install the Flex connector once for the whole workspace instead of asking every member to add it individually.

<Steps titleSize="h3">
  <Step title="Open admin Custom Connectors">
    Follow Anthropic's [Custom Connectors guide](https://support.claude.com/en/articles/11175166-get-started-with-custom-connectors-using-remote-mcp) to find the admin connector settings.
  </Step>

  <Step title="Add Flex">
    Paste `https://mcp.withflex.com/api/mcp/oauth` as the connector URL, set the name to "Flex", and save.
  </Step>

  <Step title="Members sign in on first use">
    Each workspace member will be prompted to authenticate with their own Flex login the first time they use a Flex tool — there's no shared service account.
  </Step>
</Steps>

## Claude Code

For developers using [Claude Code](https://claude.com/claude-code) in the terminal.

<Tabs>
  <Tab title="OAuth (recommended)">
    Run:

    ```bash theme={null}
    claude mcp add flex --transport http https://mcp.withflex.com/api/mcp/oauth
    ```

    The first time you call a Flex tool, Claude Code will open a browser to sign in. Subsequent sessions reuse the token.
  </Tab>

  <Tab title="API key">
    Create or copy an API key from the [API keys page](https://dashboard.withflex.com/apikeys) in your Flex Dashboard. Use an `fsk_test_…` key for experimentation.

    ```bash theme={null}
    claude mcp add flex --transport http https://mcp.withflex.com/api/mcp \
      --header "Authorization: Bearer fsk_YOUR_API_KEY"
    ```

    <Note>
      🧪 Heads up — with the API key path, the key prefix encodes the mode: `fsk_test_…` always hits test data, `fsk_…` always hits live. There's no per-call test-mode flag. See [Authentication](/developer-guides/integration/mcp/authentication) for details.
    </Note>
  </Tab>
</Tabs>

Confirm the connection from any prompt:

```
List the MCP tools available from Flex.
```

## Other MCP clients

The Flex MCP works with any client that supports the Model Context Protocol. For Cursor, Windsurf, VS Code, and Claude Desktop, the easiest path is to visit [mcp.withflex.com](https://mcp.withflex.com) — pick your client and auth method, then click the one-click install link or copy the generated config.

If you're wiring up a client we don't list explicitly, here's what you need:

| Field              | Value                                    |
| :----------------- | :--------------------------------------- |
| **Transport**      | HTTP (streamable)                        |
| **OAuth URL**      | `https://mcp.withflex.com/api/mcp/oauth` |
| **API key URL**    | `https://mcp.withflex.com/api/mcp`       |
| **API key header** | `Authorization: Bearer fsk_…`            |

A minimal JSON config (the shape most clients accept) looks like:

```json theme={null}
{
  "mcpServers": {
    "flex": {
      "type": "http",
      "url": "https://mcp.withflex.com/api/mcp/oauth"
    }
  }
}
```

For the API key path, add a `headers` object with the `Authorization` bearer.

**Tested clients:** Claude.ai · Claude Desktop · Claude Code · Cursor · Windsurf · VS Code (GitHub Copilot MCP). For each of these the [Flex MCP landing page](https://mcp.withflex.com) generates the exact config snippet.

## Next steps

<CardGroup cols={2}>
  <Card title="Try sample prompts" href="/developer-guides/integration/mcp/tools" icon="wand-sparkles" iconType="regular">
    Copy-paste prompts for support, reconciliation, refunds, and reporting.
  </Card>

  <Card title="Authentication & test mode" href="/developer-guides/integration/mcp/authentication" icon="key" iconType="regular">
    How OAuth and API keys compare, and how to stay in test mode safely.
  </Card>

  <Card title="Security best practices" href="/developer-guides/integration/mcp/security" icon="shield" iconType="regular">
    Scope your API keys and rotate credentials before going live.
  </Card>
</CardGroup>