> ## Documentation Index > Fetch the complete documentation index at: https://docs.0mcp.io/llms.txt > Use this file to discover all available pages before exploring further. # FAQ > Answers about 0mcp, security, clients, usage, and plans. ## Product ### What is 0mcp? 0mcp is a managed platform that turns an existing OpenAPI document into a hosted MCP server. It handles conversion, hosting, monitoring, and [versioning](/guides/versioning), so you do not need to build that server yourself. ### What is MCP? Model Context Protocol is a shared way for AI apps to discover and use outside capabilities. Read [What is MCP?](/concepts/what-is-mcp) for a plain explanation of clients, servers, tools, resources, and prompts. ### Do I need to change my existing API? No. Your API and its business rules stay in place. Import its [OpenAPI specification](/api-sources/openapi), choose the operations to expose, and publish them as MCP tools. ### Which API formats work today? 0mcp accepts OpenAPI 3.x and Swagger 2.0 in JSON or YAML. You can upload a file, paste the document, or provide a public URL. Direct REST API, GraphQL, and Postman Collection imports are planned. ### Can I expose only selected endpoints? Yes. You choose exactly which operations become [tools](/capabilities/tools). Leave internal, administrative, payment, or sensitive operations out unless clients truly need them. ### Can I create more than one MCP server? Yes. You can create servers for different products, customers, partners, or teams. Each server has its own capabilities, published version, endpoint, and settings. ### Does 0mcp host the server? Yes. 0mcp hosts the Streamable HTTP endpoint shown on the server Setup page. You can also connect a [custom domain](/guides/custom-domain). ### Which MCP clients can connect? 0mcp provides setup for Claude Code, Claude Desktop, Cursor, Codex, and VS Code. Other clients can connect when they support remote Streamable HTTP servers and the required headers. Start with [Client setup](/guides/setup), then choose your app from the Setup group in the sidebar. ### How quickly can I get started? A small, clear OpenAPI document can become a working server in minutes. Follow the [Quick start](/get-started/quick-start) to import, publish, try, and connect it. ## Security and data ### Does 0mcp store API request or response payloads? No. Your API remains the source of truth. 0mcp records safe operational details such as status, response time, data size, and errors for [Analytics](/guides/analytics) and [Logs](/guides/logs), without saving request or response payloads. ### Does 0mcp store my upstream API key? Upstream credentials are provided by the caller for each request. 0mcp passes them to your API and leaves them out of activity records. Learn which headers are supported in the [authentication model](/concepts/authentication-model). ### Can I keep my existing authentication and permissions? Yes. Your upstream API still decides what a Bearer token or API key can do. A valid 0mcp account does not give a caller extra access to your API. ### Can I stop calls without deleting a server? Yes. Pause serving in the server settings. This stops calls without removing the server or changing its published version. ### Is 0mcp suitable for a production API? 0mcp includes managed hosting, saved versions, custom domains, authentication forwarding, analytics, and activity logs. Before production use, review every exposed tool, test with limited credentials, and follow the [safe first-server blueprint](/#a-safe-first-server). ## Versions and usage ### When do my edits become live? Draft edits do not change the endpoint. Create a version and publish it. Connected clients may need to reconnect before they see the new capability list. See [Versioning](/guides/versioning). ### What counts as a capability use? One tool call, resource read, or prompt read counts as one capability use. The count works the same regardless of which compatible AI client made the request. ### Are capability uses shared across servers and workspaces? Yes. Included capability uses are counted across the MCP servers and workspaces in the same account during the billing period. ### Does 0mcp charge for each AI client? No. Usage is based on capabilities consumed, not the number of connected clients, users, or integrations. ### Do unused included capabilities roll over? No. Included capabilities reset at the start of the next billing period. ### What happens when I need more capabilities? You can purchase an additional capability pack for the current billing period without changing your main plan. ## Plans and billing ### Can I upgrade or downgrade my plan? Yes. Upgrades take effect immediately. Downgrades apply at the start of the next billing cycle. ### Do I need a credit card to start? No. You can explore 0mcp without a credit card. Payment details are needed when you choose a paid plan. ### Can I cancel at any time? Yes. After cancellation, the subscription remains active until the end of the current billing period. For current allowances, plan features, and prices, visit the [0mcp pricing page](https://0mcp.io/pricing).