Merge remote-tracking branch 'origin/main' into ochafik/pdf-server2

Author: ochafik

.prettierignore

@@ -3,3 +3,4 @@ examples/basic-host/**/*.tsx
 examples/basic-server-*/**/*.ts
 examples/basic-server-*/**/*.tsx
 **/vendor/**
+SKILL.md

AGENTS.md

@@ -85,3 +85,7 @@ Uses npm workspaces. Examples in `examples/` are separate packages:
 - `basic-server-*` - Starter templates (vanillajs, react, vue, svelte, preact, solid). Use these as the basis for new examples.
 - `basic-host` - Reference host implementation
 - Other examples showcase specific features (charts, 3D, video, etc.)
+
+## Claude Code Plugin
+
+The `plugins/mcp-apps/` directory contains a Claude Code plugin distributed via the plugin marketplace. It provides the "Create MCP App" skill (`plugins/mcp-apps/skills/create-mcp-app/SKILL.md`) that guides users through building MCP Apps with interactive UIs.

LICENSE

@@ -1,6 +1,193 @@
+The MCP project is undergoing a licensing transition from the MIT License to the Apache License, Version 2.0 ("Apache-2.0"). All new code and specification contributions to the project are licensed under Apache-2.0. Documentation contributions (excluding specifications) are licensed under CC-BY-4.0.
+
+Contributions for which relicensing consent has been obtained are licensed under Apache-2.0. Contributions made by authors who originally licensed their work under the MIT License and who have not yet granted explicit permission to relicense remain licensed under the MIT License.
+
+No rights beyond those granted by the applicable original license are conveyed for such contributions.
+
+---
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
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+
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+          notices within Derivative Works that You distribute, alongside
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+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
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+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+---
+
 MIT License
 
-Copyright (c) 2025 Anthropic, PBC
+Copyright (c) 2024-2025 Model Context Protocol a Series of LF Projects, LLC.
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -19,3 +206,11 @@ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
+
+---
+
+Creative Commons Attribution 4.0 International (CC-BY-4.0)
+
+Documentation in this project (excluding specifications) is licensed under
+CC-BY-4.0. See https://creativecommons.org/licenses/by/4.0/legalcode for
+the full license text.

examples/basic-host/.gitignore

@@ -0,0 +1,2 @@
+node_modules/
+dist/

examples/basic-server-preact/.gitignore

@@ -0,0 +1,2 @@
+node_modules/
+dist/

examples/basic-server-preact/README.md

@@ -28,3 +28,7 @@ npm run dev
 1. The server registers a `get-time` tool with metadata linking it to a UI HTML resource (`ui://get-time/mcp-app.html`).
 2. When the tool is invoked, the Host renders the UI from the resource.
 3. The UI uses the MCP App SDK API to communicate with the host and call server tools.
+
+## Build System
+
+This example bundles into a single HTML file using Vite with `vite-plugin-singlefile` — see [`vite.config.ts`](vite.config.ts). This allows all UI content to be served as a single MCP resource. Alternatively, MCP apps can load external resources by defining [`_meta.ui.csp.resourceDomains`](https://modelcontextprotocol.github.io/ext-apps/api/interfaces/app.McpUiResourceCsp.html#resourcedomains) in the UI resource metadata.

examples/basic-server-preact/src/mcp-app.tsx

@@ -1,23 +1,18 @@
 /**
  * @file App that demonstrates a few features using MCP Apps SDK + Preact.
  */
-import { App, type McpUiHostContext } from "@modelcontextprotocol/ext-apps";
+import {
+  App,
+  applyDocumentTheme,
+  applyHostFonts,
+  applyHostStyleVariables,
+  type McpUiHostContext,
+} from "@modelcontextprotocol/ext-apps";
 import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
 import { useCallback, useEffect, useState } from "preact/hooks";
 import { render } from "preact";
 import styles from "./mcp-app.module.css";
 
-
-const IMPLEMENTATION = { name: "Get Time App", version: "1.0.0" };
-
-
-const log = {
-  info: console.log.bind(console, "[APP]"),
-  warn: console.warn.bind(console, "[APP]"),
-  error: console.error.bind(console, "[APP]"),
-};
-
-
 function extractTime(callToolResult: CallToolResult): string {
   const { text } = callToolResult.content?.find((c) => c.type === "text")!;
   return text;
@@ -30,19 +25,36 @@ function GetTimeApp() {
   const [toolResult, setToolResult] = useState<CallToolResult | null>(null);
   const [hostContext, setHostContext] = useState<McpUiHostContext | undefined>();
 
+  // Apply host styles reactively when hostContext changes
+  useEffect(() => {
+    if (hostContext?.theme) {
+      applyDocumentTheme(hostContext.theme);
+    }
+    if (hostContext?.styles?.variables) {
+      applyHostStyleVariables(hostContext.styles.variables);
+    }
+    if (hostContext?.styles?.css?.fonts) {
+      applyHostFonts(hostContext.styles.css.fonts);
+    }
+  }, [hostContext]);
+
   useEffect(() => {
-    const instance = new App(IMPLEMENTATION);
+    const instance = new App({ name: "Get Time App", version: "1.0.0" });
 
     instance.ontoolinput = async (input) => {
-      log.info("Received tool call input:", input);
+      console.info("Received tool call input:", input);
     };
 
     instance.ontoolresult = async (result) => {
-      log.info("Received tool call result:", result);
+      console.info("Received tool call result:", result);
       setToolResult(result);
     };
 
-    instance.onerror = log.error;
+    instance.ontoolcancelled = (params) => {
+      console.info("Tool call cancelled:", params.reason);
+    };
+
+    instance.onerror = console.error;
 
     instance.onhostcontextchanged = (params) => {
       setHostContext((prev) => ({ ...prev, ...params }));
@@ -83,39 +95,39 @@ function GetTimeAppInner({ app, toolResult, hostContext }: GetTimeAppInnerProps)
 
   const handleGetTime = useCallback(async () => {
     try {
-      log.info("Calling get-time tool...");
+      console.info("Calling get-time tool...");
       const result = await app.callServerTool({ name: "get-time", arguments: {} });
-      log.info("get-time result:", result);
+      console.info("get-time result:", result);
       setServerTime(extractTime(result));
     } catch (e) {
-      log.error(e);
+      console.error(e);
       setServerTime("[ERROR]");
     }
   }, [app]);
 
   const handleSendMessage = useCallback(async () => {
     const signal = AbortSignal.timeout(5000);
     try {
-      log.info("Sending message text to Host:", messageText);
+      console.info("Sending message text to Host:", messageText);
       const { isError } = await app.sendMessage(
         { role: "user", content: [{ type: "text", text: messageText }] },
         { signal },
       );
-      log.info("Message", isError ? "rejected" : "accepted");
+      console.info("Message", isError ? "rejected" : "accepted");
     } catch (e) {
-      log.error("Message send error:", signal.aborted ? "timed out" : e);
+      console.error("Message send error:", signal.aborted ? "timed out" : e);
     }
   }, [app, messageText]);
 
   const handleSendLog = useCallback(async () => {
-    log.info("Sending log text to Host:", logText);
+    console.info("Sending log text to Host:", logText);
     await app.sendLog({ level: "info", data: logText });
   }, [app, logText]);
 
   const handleOpenLink = useCallback(async () => {
-    log.info("Sending open link request to Host:", linkUrl);
+    console.info("Sending open link request to Host:", linkUrl);
     const { isError } = await app.openLink({ url: linkUrl });
-    log.info("Open link request", isError ? "rejected" : "accepted");
+    console.info("Open link request", isError ? "rejected" : "accepted");
   }, [app, linkUrl]);
 
   return (

examples/basic-server-react/.gitignore

@@ -0,0 +1,2 @@
+node_modules/
+dist/

examples/basic-server-react/README.md

@@ -30,3 +30,7 @@ npm run dev
 1. The server registers a `get-time` tool with metadata linking it to a UI HTML resource (`ui://get-time/mcp-app.html`).
 2. When the tool is invoked, the Host renders the UI from the resource.
 3. The UI uses the MCP App SDK API to communicate with the host and call server tools.
+
+## Build System
+
+This example bundles into a single HTML file using Vite with `vite-plugin-singlefile` — see [`vite.config.ts`](vite.config.ts). This allows all UI content to be served as a single MCP resource. Alternatively, MCP apps can load external resources by defining [`_meta.ui.csp.resourceDomains`](https://modelcontextprotocol.github.io/ext-apps/api/interfaces/app.McpUiResourceCsp.html#resourcedomains) in the UI resource metadata.