# moonpeak

> Server-agnostic MCP testing framework and full-stack MCP App framework. Build, inspect and test MCP Apps (interactive UIs) for ChatGPT, Claude and every MCP Apps host. Open source, MIT, npm package `moonpeak`.

Start a project with `npx moonpeak new`. A live demo MCP server runs at https://moonpeak-ai.com/mcp. Every page below is also available as Markdown, and https://moonpeak-ai.com/docs/llms-full.txt has all of them in one file.

## Get started

- [Overview](https://moonpeak-ai.com/docs/index.md): Server-agnostic MCP testing framework and full-stack MCP App framework.
- [Quickstart](https://moonpeak-ai.com/docs/quickstart/index.md): From npx moonpeak new to a View rendering in Claude.
- [Project scaffold](https://moonpeak-ai.com/docs/project-scaffold/index.md): What npx moonpeak new creates, and how moonpeak discovers tools, Views and tests.
- [Configuration](https://moonpeak-ai.com/docs/configuration/index.md): moonpeak works without a config file. moonpeak.config.js is there when you need it.

## App Framework

- [Tools](https://moonpeak-ai.com/docs/app-framework/tools/index.md): One file in src/tools is one MCP tool: metadata, a zod schema and a handler.
- [Views](https://moonpeak-ai.com/docs/app-framework/views/index.md): One folder in src/resources is one View: a React component the host renders next to the chat.
- [Runtime APIs](https://moonpeak-ai.com/docs/app-framework/runtime-apis/index.md): Every hook a View can use, from moonpeak, moonpeak/chatgpt and moonpeak/claude.
- [ChatGPT Apps](https://moonpeak-ai.com/docs/app-framework/chatgpt/index.md): A moonpeak project is a ChatGPT App. What moonpeak adds for ChatGPT, and how to try it.
- [Claude connectors](https://moonpeak-ai.com/docs/app-framework/claude/index.md): A moonpeak project is a Claude connector with interactive UI.
- [MCP server](https://moonpeak-ai.com/docs/app-framework/mcp-server/index.md): The server moonpeak builds from your tools and Views, and how to use it directly.
- [Production server](https://moonpeak-ai.com/docs/app-framework/production-server/index.md): moonpeak build and moonpeak start, and how to mount the build on another runtime.

## Hooks

- [useToolData](https://moonpeak-ai.com/docs/hooks/use-tool-data/index.md): Tool data hook from moonpeak.
- [useToolInput](https://moonpeak-ai.com/docs/hooks/use-tool-input/index.md): Tool data hook from moonpeak.
- [useToolOutput](https://moonpeak-ai.com/docs/hooks/use-tool-output/index.md): Tool data hook from moonpeak.
- [useToolResult](https://moonpeak-ai.com/docs/hooks/use-tool-result/index.md): Tool data hook from moonpeak.
- [useTheme](https://moonpeak-ai.com/docs/hooks/use-theme/index.md): Host context hook from moonpeak.
- [useDisplayMode](https://moonpeak-ai.com/docs/hooks/use-display-mode/index.md): Host context hook from moonpeak.
- [useRequestDisplayMode](https://moonpeak-ai.com/docs/hooks/use-request-display-mode/index.md): Host context hook from moonpeak.
- [useHostContext](https://moonpeak-ai.com/docs/hooks/use-host-context/index.md): Host context hook from moonpeak.
- [useLocale](https://moonpeak-ai.com/docs/hooks/use-locale/index.md): Host context hook from moonpeak.
- [useTimeZone](https://moonpeak-ai.com/docs/hooks/use-time-zone/index.md): Host context hook from moonpeak.
- [usePlatform](https://moonpeak-ai.com/docs/hooks/use-platform/index.md): Host context hook from moonpeak.
- [useDeviceCapabilities](https://moonpeak-ai.com/docs/hooks/use-device-capabilities/index.md): Host context hook from moonpeak.
- [useSafeArea](https://moonpeak-ai.com/docs/hooks/use-safe-area/index.md): Host context hook from moonpeak.
- [useContainerSize](https://moonpeak-ai.com/docs/hooks/use-container-size/index.md): Host context hook from moonpeak.
- [useMaxHeight](https://moonpeak-ai.com/docs/hooks/use-max-height/index.md): Host context hook from moonpeak.
- [useHost](https://moonpeak-ai.com/docs/hooks/use-host/index.md): Host hook from moonpeak.
- [useHostCapabilities](https://moonpeak-ai.com/docs/hooks/use-host-capabilities/index.md): Host hook from moonpeak.
- [useConnection](https://moonpeak-ai.com/docs/hooks/use-connection/index.md): Host hook from moonpeak.
- [useApp](https://moonpeak-ai.com/docs/hooks/use-app/index.md): Host hook from moonpeak.
- [useCallTool](https://moonpeak-ai.com/docs/hooks/use-call-tool/index.md): Actions hook from moonpeak.
- [useSendMessage](https://moonpeak-ai.com/docs/hooks/use-send-message/index.md): Actions hook from moonpeak.
- [useUpdateModelContext](https://moonpeak-ai.com/docs/hooks/use-update-model-context/index.md): Actions hook from moonpeak.
- [useOpenLink](https://moonpeak-ai.com/docs/hooks/use-open-link/index.md): Actions hook from moonpeak.
- [useDownloadFile](https://moonpeak-ai.com/docs/hooks/use-download-file/index.md): Actions hook from moonpeak.
- [useLog](https://moonpeak-ai.com/docs/hooks/use-log/index.md): Actions hook from moonpeak.
- [useAppState](https://moonpeak-ai.com/docs/hooks/use-app-state/index.md): State hook from moonpeak.
- [useResultState](https://moonpeak-ai.com/docs/hooks/use-result-state/index.md): State hook from moonpeak.
- [useIsChatGPT](https://moonpeak-ai.com/docs/hooks/use-is-chat-gpt/index.md): ChatGPT hook from moonpeak/chatgpt.
- [useWidgetState](https://moonpeak-ai.com/docs/hooks/use-widget-state/index.md): ChatGPT hook from moonpeak/chatgpt.
- [useOpenAiGlobal](https://moonpeak-ai.com/docs/hooks/use-open-ai-global/index.md): ChatGPT hook from moonpeak/chatgpt.
- [useUploadFile](https://moonpeak-ai.com/docs/hooks/use-upload-file/index.md): ChatGPT hook from moonpeak/chatgpt.
- [useRequestModal](https://moonpeak-ai.com/docs/hooks/use-request-modal/index.md): ChatGPT hook from moonpeak/chatgpt.
- [useUserAgent](https://moonpeak-ai.com/docs/hooks/use-user-agent/index.md): ChatGPT hook from moonpeak/chatgpt.
- [useIsClaude](https://moonpeak-ai.com/docs/hooks/use-is-claude/index.md): Claude hook from moonpeak/claude.
- [useClaudeStyles](https://moonpeak-ai.com/docs/hooks/use-claude-styles/index.md): Claude hook from moonpeak/claude.

## Starter resources

- [moon](https://moonpeak-ai.com/docs/resources/moon/index.md): Detail card: a date's moon phase, a 7-day strip, and buttons that call the tool again through the host.
- [calendar](https://moonpeak-ai.com/docs/resources/calendar/index.md): Carousel: swipeable cards of the upcoming moon phases, loading more through the host.
- [review](https://moonpeak-ai.com/docs/resources/review/index.md): Review and confirm: the model proposes a stargazing night, the user confirms it in the UI through an app-only tool.

## CLI

- [moonpeak new](https://moonpeak-ai.com/docs/cli/new/index.md): Scaffold a project, picking which starter resources to include.
- [moonpeak dev](https://moonpeak-ai.com/docs/cli/dev/index.md): MCP server and inspector with hot reload, on one port.
- [moonpeak build](https://moonpeak-ai.com/docs/cli/build/index.md): Bundle every View into one HTML file and your tools into dist/server.mjs.
- [moonpeak start](https://moonpeak-ai.com/docs/cli/start/index.md): Serve a build at /mcp.
- [moonpeak inspect](https://moonpeak-ai.com/docs/cli/inspect/index.md): Open the inspector against any MCP server.
- [moonpeak test](https://moonpeak-ai.com/docs/cli/test/index.md): Every testing mode in one command.
- [moonpeak upgrade](https://moonpeak-ai.com/docs/cli/upgrade/index.md): Update moonpeak in the current project.

## Testing Framework

- [Testing Framework](https://moonpeak-ai.com/docs/testing/index.md): Test MCP Apps and any MCP server in CI, without host accounts, tunnels or AI credits.
- [Simulations](https://moonpeak-ai.com/docs/testing/simulations/index.md): JSON fixtures for a tool: input, optional mocked output, expectations and host settings.
- [In-process checks](https://moonpeak-ai.com/docs/testing/unit/index.md): What moonpeak test checks, in seconds, with no browser.
- [E2E testing](https://moonpeak-ai.com/docs/testing/e2e/index.md): Playwright tests against the inspector, in ChatGPT and Claude style hosts.
- [Visual regression](https://moonpeak-ai.com/docs/testing/visual/index.md): Screenshot tests tagged @visual.
- [Evals](https://moonpeak-ai.com/docs/testing/evals/index.md): Check that real models pick the right tool with the right arguments.
- [Any MCP server](https://moonpeak-ai.com/docs/testing/any-server/index.md): Test and inspect MCP servers written in Python, Go, Rust, Java or anything else.
- [CI](https://moonpeak-ai.com/docs/testing/ci/index.md): Run moonpeak tests in GitHub Actions.

## Inspector

- [Inspector](https://moonpeak-ai.com/docs/inspector/index.md): ChatGPT-style and Claude-style hosts on localhost.
- [URL parameters](https://moonpeak-ai.com/docs/inspector/url-parameters/index.md): Every inspector setting is in the URL, so a bug report is a link.
- [Remote servers](https://moonpeak-ai.com/docs/inspector/remote/index.md): Inspect an MCP server you didn't build with moonpeak.

## MCP Apps

- [MCP Apps](https://moonpeak-ai.com/docs/mcp-apps/index.md): What MCP Apps are and how a host renders one.
- [Lifecycle](https://moonpeak-ai.com/docs/mcp-apps/lifecycle/index.md): The order in which a View receives data, and what each state means.
- [Display modes & layout](https://moonpeak-ai.com/docs/mcp-apps/display-modes/index.md): Inline, picture-in-picture and fullscreen, and how to size a View.
- [State persistence](https://moonpeak-ai.com/docs/mcp-apps/state/index.md): Keeping what the user did in a View across reloads, and sharing it with the model.
- [Tool visibility](https://moonpeak-ai.com/docs/mcp-apps/visibility/index.md): Tools only the model can call, only the View can call, or both.
- [Security & CSP](https://moonpeak-ai.com/docs/mcp-apps/security/index.md): What a View can and cannot do, and how to allow more.
- [Tool results](https://moonpeak-ai.com/docs/mcp-apps/tool-results/index.md): content, structuredContent and _meta: who reads what.

## Guides

- [Deployment](https://moonpeak-ai.com/docs/guides/deployment/index.md): Put a moonpeak server on the internet over HTTPS.
- [Authorization](https://moonpeak-ai.com/docs/guides/authorization/index.md): Protecting a moonpeak server and testing protected servers.
- [Patterns](https://moonpeak-ai.com/docs/guides/patterns/index.md): Shapes that work well for MCP Apps.
- [Troubleshooting](https://moonpeak-ai.com/docs/guides/troubleshooting/index.md): Common problems and their fixes.

## Site

- [MCP App framework](https://moonpeak-ai.com/mcp-app-framework/)
- [MCP testing framework](https://moonpeak-ai.com/testing-framework/)
- [MCP App inspector](https://moonpeak-ai.com/mcp-app-inspector/)
- [FAQs](https://moonpeak-ai.com/faqs/)
- [Source on GitHub](https://github.com/ghiansalman30-crypto/moonpeak)