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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.

The Flex MCP server lets AI assistants like Claude, Cursor, and Windsurf interact with your Flex account on your behalf. Ask your AI to look up a payment intent, summarize yesterday’s refunds, or create a new product — and it’ll call the Flex API directly through a secure, authenticated connection.

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What is MCP?

The Model Context Protocol is an open standard for connecting AI assistants to external tools and data. Once you wire up the Flex MCP, your AI assistant gets a set of typed tools — create_product, list_payment_intents, refund_capture, and so on — that mirror the Flex API. The assistant chooses which to call based on your prompt; you stay in control through tool-use approval prompts in the client.

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What you can do with the Flex MCP

  • Customer support — Look up an order or payment intent by ID in plain English, with the full context the API returns.
  • Reconciliation — Pull yesterday’s captured payments, group by product, and compare against your fulfillment system.
  • Refunds & disputes — Draft a dispute response from order details, or issue a refund after a customer support conversation.
  • Subscription ops — Query active subscriptions, find upcoming renewals, or update billing details on a customer.
  • Reporting — Ask for weekly capture volume, top products by revenue, or a list of new customers in a date range.
See the Tools & sample prompts page for concrete examples you can copy into your assistant.

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Authentication

The Flex MCP supports two ways to authenticate, and you should pick based on which client you’re using:
Auth modeBest forHow it works
OAuthClaude.ai, Claude Desktop, any client with a browserClick “Connect”, sign in with your Flex account, approve access. No API key to manage.
API keyClaude Code and other headless agentsPaste an fsk_… (live) or fsk_test_… (test) API key in the client’s MCP config.
Both modes scope access to your partner — you only ever see your own data. See Authentication for details on how test mode works in each.
An MCP client connected to your Flex account has the same level of access as the credentials you provide. With OAuth, that’s the same access as the signed-in user; with an API key, it’s whatever scopes that key was issued. AI assistants can make mistakes — read the Security best practices before connecting a live (non-test) account.

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Get started

Quick start

Connect Claude.ai, Claude Code, or another MCP client in under five minutes.

Tools & sample prompts

See the tools the Flex MCP exposes, with copy-paste prompts you can try.

Authentication

OAuth vs. API key, plus how test mode behaves in each.

Security best practices

Scope your keys, stay in test mode while experimenting, and rotate credentials.