From 256d48f32db21e381286692f0a1bccfec245ff9e Mon Sep 17 00:00:00 2001
From: rgarcia <72655+rgarcia@users.noreply.github.com>
Date: Sun, 1 Nov 2026 18:51:37 +0000
Subject: [PATCH 1/2] Copy destructiveHint to WebMCP's consequentialHint when
 it is not set

---
 js/README.md         |  4 +++-
 js/src/index.ts      | 19 +++++++++++++++++--
 js/test/core.test.ts | 18 ++++++++++++++++++
 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/js/README.md b/js/README.md
index fb03e5b6..2e713af8 100644
--- a/js/README.md
+++ b/js/README.md
@@ -245,7 +245,9 @@ point of view. A full page load ends the call before it can return.
 | `xwebmcp` | `registerTool(tool, { signal })`, `refresh()`, `getModelContext()`, `availableToolNames()`, `subscribe(listener)`; no React |
 
 `useWebMCPTool({ name, description, inputSchema?, outputSchema?, annotations?, title?, execute, enabled? })`
-takes the fields of a WebMCP tool plus `enabled`.
+takes the fields of a WebMCP tool plus `enabled`. Chrome reads `consequentialHint` rather than
+MCP's `destructiveHint`; when only the latter is set it is copied over, so a destructive tool is
+marked as needing confirmation.
 
 `useWebMCPRoute({ path, description, enabled? })`.
 
diff --git a/js/src/index.ts b/js/src/index.ts
index 4114058c..97683570 100644
--- a/js/src/index.ts
+++ b/js/src/index.ts
@@ -6,6 +6,11 @@ export interface ToolAnnotations {
   idempotentHint?: boolean;
   openWorldHint?: boolean;
   untrustedContentHint?: boolean;
+  /**
+   * WebMCP's name for an action with effects the user would want to confirm.
+   * Defaults to `destructiveHint`, so MCP-style annotations carry over.
+   */
+  consequentialHint?: boolean;
 }
 
 export interface WebMCPTool<Input = any, Output = unknown> {
@@ -121,6 +126,11 @@ function notify() {
   for (const listener of listeners) listener();
 }
 
+function withConsequentialHint(annotations: ToolAnnotations): ToolAnnotations {
+  if (annotations.consequentialHint !== undefined || annotations.destructiveHint === undefined) return annotations;
+  return { ...annotations, consequentialHint: annotations.destructiveHint };
+}
+
 function sync(name: string) {
   const ctx = context();
   if (!ctx) return;
@@ -134,14 +144,19 @@ function sync(name: string) {
   if (top) {
     const controller = new AbortController();
     active.set(name, { tool: top, controller });
-    const { execute, ...definition } = top;
+    const { execute, annotations, ...definition } = top;
     // Deferred so that replacing a registration within one task only
     // registers the final one with the browser.
     Promise.resolve()
       .then(() => {
         if (controller.signal.aborted) return;
         return ctx.registerTool(
-          { inputSchema: { type: 'object', properties: {} }, ...definition, execute },
+          {
+            inputSchema: { type: 'object', properties: {} },
+            ...definition,
+            ...(annotations ? { annotations: withConsequentialHint(annotations) } : {}),
+            execute,
+          },
           { signal: controller.signal },
         );
       })
diff --git a/js/test/core.test.ts b/js/test/core.test.ts
index 3e8a2352..b64e6831 100644
--- a/js/test/core.test.ts
+++ b/js/test/core.test.ts
@@ -114,6 +114,24 @@ describe('with WebMCP', () => {
     expect(ctx.tools.has('a')).toBe(true);
   });
 
+  it('derives consequentialHint from destructiveHint', async () => {
+    const ctx = installFakeModelContext();
+    core.registerTool({ ...tool('a'), annotations: { destructiveHint: true } }, { signal: new AbortController().signal });
+    core.registerTool(
+      { ...tool('b'), annotations: { destructiveHint: true, consequentialHint: false } },
+      { signal: new AbortController().signal },
+    );
+    await flush();
+    expect((ctx.tools.get('a') as { annotations?: object }).annotations).toEqual({
+      destructiveHint: true,
+      consequentialHint: true,
+    });
+    expect((ctx.tools.get('b') as { annotations?: object }).annotations).toEqual({
+      destructiveHint: true,
+      consequentialHint: false,
+    });
+  });
+
   it('lists tools registered outside this package', async () => {
     const ctx = installFakeModelContext();
     ctx.registerTool({ ...tool('native'), inputSchema: {} }, { signal: new AbortController().signal });

From 607260bfba0bcfcf89e1f09fb858e18209d51288 Mon Sep 17 00:00:00 2001
From: rgarcia <72655+rgarcia@users.noreply.github.com>
Date: Sun, 1 Nov 2026 19:05:12 +0000
Subject: [PATCH 2/2] xwebmcp 0.1.2

---
 js/package-lock.json | 4 ++--
 js/package.json      | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/js/package-lock.json b/js/package-lock.json
index 7f36777a..564bc5c1 100644
--- a/js/package-lock.json
+++ b/js/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "xwebmcp",
-  "version": "0.1.1",
+  "version": "0.1.2",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "xwebmcp",
-      "version": "0.1.1",
+      "version": "0.1.2",
       "license": "UNLICENSED",
       "devDependencies": {
         "@testing-library/react": "^16.3.3",
diff --git a/js/package.json b/js/package.json
index 63d5187f..232a1641 100644
--- a/js/package.json
+++ b/js/package.json
@@ -1,6 +1,6 @@
 {
   "name": "xwebmcp",
-  "version": "0.1.1",
+  "version": "0.1.2",
   "description": "Register WebMCP tools from React and Next.js components, with distributed get_page_context and navigate_to_page tools.",
   "license": "MIT",
   "repository": {