WebMCP: Reject invalid origins with "NotSupportedError"

webmcp/declarative/opaque-origin-tools.https.html

@@ -25,9 +25,9 @@
 
   await promise_rejects_dom(
     t,
-    'DataError',
+    'NotSupportedError',
     document.modelContext.executeTool(tool, '{"param1":"value"}'),
-    'executeTool() must reject with DataError in opaque origin documents'
+    'executeTool() must reject with NotSupportedError in opaque origin documents'
   );
 }, 'An opaque origin document can register but not execute its own declarative tools');
 
@@ -48,9 +48,9 @@
 
   await promise_rejects_dom(
     t,
-    'DataError',
+    'NotSupportedError',
     document.modelContext.executeTool(tool, '{"param1":"value"}'),
-    'executeTool() must reject with DataError in opaque origin documents'
+    'executeTool() must reject with NotSupportedError in opaque origin documents'
   );
 
   assert_array_equals(events, ['rejection', 'microtask'],

webmcp/imperative/opaque-origin-tools.https.html

@@ -25,15 +25,28 @@
 
   await promise_rejects_dom(
     t,
-    'DataError',
+    'NotSupportedError',
     document.modelContext.executeTool(tool, '{}'),
-    'executeTool() must reject with DataError in opaque origin documents'
+    'executeTool() must reject with NotSupportedError in opaque origin documents'
   );
 }, 'An opaque origin document can register but not execute its own tools');
 
+// The below three tests are almost the same, with the following distinctions:
+//   1. The first test asserts that executing a tool whose origin as returned
+//      from `getTools()` is "null", synchronously rejects the execution
+//      Promise. "null" fails to parse as a URL, because we don't parse it
+//      relative to the document's URL as a base URL.
+//   2. The second and third tests below, captured by
+//      `invalid_execution_origins`, don't reference legitimately-registered
+//      tools. Instead, they test when the passed-in tool origin is:
+//
+//     a.) An invalid URL that's not a single "null" string value. Rather, it's
+//         an `https://` URL that fails to parse due to an invalid port.
+//     b.) A string that successfully parses as a URL, but whose origin is opaque.
 promise_test(async t => {
   const tools = await document.modelContext.getTools();
   const tool = tools.find(t => t.name === 'opaque_tool');
+  assert_equals(tool.origin, "null", "getTools() gives");
 
   let events = [];
   const p = document.modelContext.executeTool(tool, '{}');
@@ -48,14 +61,41 @@
 
   await promise_rejects_dom(
     t,
-    'DataError',
+    'NotSupportedError',
     document.modelContext.executeTool(tool, '{"param1":"value"}'),
-    'executeTool() must reject with DataError in opaque origin documents'
+    'executeTool() must reject with NotSupportedError in opaque origin documents'
   );
 
   assert_array_equals(events, ['rejection', 'microtask'],
     'returned promise is rejected before custom microtask is queued');
-}, 'executeTool() rejects synchronously for opaque origins');
+}, 'executeTool() rejects synchronously for origin "null" that fails to parse as a URL');
+
+const invalid_execution_origins = ["https://test.example:invalidport", "data:text/html,foo"];
+for (const invalid_origin of invalid_execution_origins) {
+  promise_test(async t => {
+    const fake_tool = {
+      name: 'data_opaque_tool',
+      description: 'Data URL opaque tool description',
+      window: window,
+      origin: invalid_origin
+    };
+
+    let events = [];
+    const p = document.modelContext.executeTool(fake_tool, '{}');
+    p.catch(() => events.push('rejection'));
+
+    // Queue another microtask immediately after.
+    queueMicrotask(() => events.push('microtask'));
+
+    await promise_rejects_dom(
+      t,
+      'NotSupportedError',
+      document.modelContext.executeTool(fake_tool, '{"param1":"value"}'));
+
+    assert_array_equals(events, ['rejection', 'microtask'],
+      'returned promise is rejected before custom microtask is queued');
+  }, `executeTool() rejects synchronously for invalid origin: ${invalid_origin}`);
+}
 </script>
 </body>
 </html>