diff --git a/packages/frontend-plugin-api/api-report.md b/packages/frontend-plugin-api/api-report.md
index e1ed76d82c..dcd2cbda4b 100644
--- a/packages/frontend-plugin-api/api-report.md
+++ b/packages/frontend-plugin-api/api-report.md
@@ -376,23 +376,18 @@ export type CoreProgressComponent = ComponentType<PropsWithChildren<{}>>;
 export function createApiExtension<
   TConfig extends {},
   TInputs extends AnyExtensionInputMap,
->(
-  options: (
-    | {
-        api: AnyApiRef;
-        factory: (options: {
-          config: TConfig;
-          inputs: Expand<ExtensionInputValues<TInputs>>;
-        }) => AnyApiFactory;
-      }
-    | {
-        factory: AnyApiFactory;
-      }
-  ) & {
-    configSchema?: PortableSchema<TConfig>;
-    inputs?: TInputs;
-  },
-): Extension<TConfig>;
+>(options: {
+  factory:
+    | AnyApiFactory
+    | ((options: {
+        config: TConfig;
+        inputs: Expand<ExtensionInputValues<TInputs>>;
+      }) => AnyApiFactory);
+  namespace?: string;
+  name?: string;
+  configSchema?: PortableSchema<TConfig>;
+  inputs?: TInputs;
+}): ExtensionDefinition<TConfig>;
 
 export { createApiFactory };
 
@@ -430,7 +425,7 @@ export function createExtension<
   TConfig = never,
 >(
   options: CreateExtensionOptions<TOutput, TInputs, TConfig>,
-): Extension<TConfig>;
+): ExtensionDefinition<TConfig>;
 
 // @public (undocumented)
 export function createExtensionDataRef<TData>(
@@ -477,10 +472,14 @@ export interface CreateExtensionOptions<
     inputs: Expand<ExtensionInputValues<TInputs>>;
   }): Expand<ExtensionDataValues<TOutput>>;
   // (undocumented)
-  id: string;
-  // (undocumented)
   inputs?: TInputs;
   // (undocumented)
+  kind?: string;
+  // (undocumented)
+  name?: string;
+  // (undocumented)
+  namespace?: string;
+  // (undocumented)
   output: TOutput;
 }
 
@@ -516,11 +515,12 @@ export function createExternalRouteRef<
 
 // @public
 export function createNavItemExtension(options: {
-  id: string;
+  namespace?: string;
+  name?: string;
   routeRef: RouteRef<undefined>;
   title: string;
   icon: IconComponent_2;
-}): Extension<{
+}): ExtensionDefinition<{
   title: string;
 }>;
 
@@ -539,7 +539,8 @@ export function createPageExtension<
         configSchema: PortableSchema<TConfig>;
       }
   ) & {
-    id: string;
+    namespace?: string;
+    name?: string;
     attachTo?: {
       id: string;
       input: string;
@@ -552,7 +553,7 @@ export function createPageExtension<
       inputs: Expand<ExtensionInputValues<TInputs>>;
     }) => Promise<JSX.Element>;
   },
-): Extension<TConfig>;
+): ExtensionDefinition<TConfig>;
 
 // @public (undocumented)
 export function createPlugin<
@@ -616,7 +617,9 @@ export function createSubRouteRef<
 }): MakeSubRouteRef<PathParams<Path>, ParentParams>;
 
 // @public (undocumented)
-export function createThemeExtension(theme: AppTheme): Extension<never>;
+export function createThemeExtension(
+  theme: AppTheme,
+): ExtensionDefinition<never>;
 
 export { DiscoveryApi };
 
@@ -703,6 +706,40 @@ export type ExtensionDataValues<TExtensionData extends AnyExtensionDataMap> = {
     : never]?: TExtensionData[DataName]['T'];
 };
 
+// @public (undocumented)
+export interface ExtensionDefinition<TConfig> {
+  // (undocumented)
+  $$type: '@backstage/ExtensionDefinition';
+  // (undocumented)
+  attachTo: {
+    id: string;
+    input: string;
+  };
+  // (undocumented)
+  configSchema?: PortableSchema<TConfig>;
+  // (undocumented)
+  disabled: boolean;
+  // (undocumented)
+  factory(options: {
+    node: AppNode;
+    config: TConfig;
+    inputs: Record<
+      string,
+      undefined | Record<string, unknown> | Array<Record<string, unknown>>
+    >;
+  }): ExtensionDataValues<any>;
+  // (undocumented)
+  inputs: AnyExtensionInputMap;
+  // (undocumented)
+  kind?: string;
+  // (undocumented)
+  name?: string;
+  // (undocumented)
+  namespace?: string;
+  // (undocumented)
+  output: AnyExtensionDataMap;
+}
+
 // @public (undocumented)
 export interface ExtensionInput<
   TExtensionData extends AnyExtensionDataMap,
@@ -743,7 +780,7 @@ export interface ExtensionOverrides {
 // @public (undocumented)
 export interface ExtensionOverridesOptions {
   // (undocumented)
-  extensions: Extension<unknown>[];
+  extensions: ExtensionDefinition<unknown>[];
   // (undocumented)
   featureFlags?: FeatureFlagConfig[];
 }
@@ -841,7 +878,7 @@ export interface PluginOptions<
   ExternalRoutes extends AnyExternalRoutes,
 > {
   // (undocumented)
-  extensions?: Extension<unknown>[];
+  extensions?: ExtensionDefinition<unknown>[];
   // (undocumented)
   externalRoutes?: ExternalRoutes;
   // (undocumented)
diff --git a/packages/frontend-test-utils/api-report.md b/packages/frontend-test-utils/api-report.md
index 59f5696ddc..14e1c68c4c 100644
--- a/packages/frontend-test-utils/api-report.md
+++ b/packages/frontend-test-utils/api-report.md
@@ -4,7 +4,7 @@
 
 ```ts
 import { ErrorWithContext } from '@backstage/test-utils';
-import { Extension } from '@backstage/frontend-plugin-api';
+import { ExtensionDefinition } from '@backstage/frontend-plugin-api';
 import { JsonObject } from '@backstage/types';
 import { MockAnalyticsApi } from '@backstage/test-utils';
 import { MockConfigApi } from '@backstage/test-utils';
@@ -24,7 +24,7 @@ import { withLogCollector } from '@backstage/test-utils';
 
 // @public (undocumented)
 export function createExtensionTester<TConfig>(
-  subject: Extension<TConfig>,
+  subject: ExtensionDefinition<TConfig>,
   options?: {
     config?: TConfig;
   },
@@ -36,7 +36,7 @@ export { ErrorWithContext };
 export class ExtensionTester {
   // (undocumented)
   add<TConfig>(
-    extension: Extension<TConfig>,
+    extension: ExtensionDefinition<TConfig>,
     options?: {
       config?: TConfig;
     },
diff --git a/plugins/adr/api-report-alpha.md b/plugins/adr/api-report-alpha.md
index 3864c85697..4c9ac1d17e 100644
--- a/plugins/adr/api-report-alpha.md
+++ b/plugins/adr/api-report-alpha.md
@@ -4,11 +4,11 @@
 
 ```ts
 import { BackstagePlugin } from '@backstage/frontend-plugin-api';
-import { Extension } from '@backstage/frontend-plugin-api';
+import { ExtensionDefinition } from '@backstage/frontend-plugin-api';
 import { TranslationRef } from '@backstage/core-plugin-api/alpha';
 
 // @alpha (undocumented)
-export const AdrSearchResultListItemExtension: Extension<{
+export const AdrSearchResultListItemExtension: ExtensionDefinition<{
   lineClamp: number;
   noTrack: boolean;
 }>;
diff --git a/plugins/catalog-react/api-report-alpha.md b/plugins/catalog-react/api-report-alpha.md
index 913055f8b0..1be108f695 100644
--- a/plugins/catalog-react/api-report-alpha.md
+++ b/plugins/catalog-react/api-report-alpha.md
@@ -8,7 +8,7 @@
 import { AnyExtensionInputMap } from '@backstage/frontend-plugin-api';
 import { ConfigurableExtensionDataRef } from '@backstage/frontend-plugin-api';
 import { Entity } from '@backstage/catalog-model';
-import { Extension } from '@backstage/frontend-plugin-api';
+import { ExtensionDefinition } from '@backstage/frontend-plugin-api';
 import { ExtensionInputValues } from '@backstage/frontend-plugin-api';
 import { ResourcePermission } from '@backstage/plugin-permission-common';
 import { RouteRef } from '@backstage/frontend-plugin-api';
@@ -17,7 +17,8 @@ import { RouteRef } from '@backstage/frontend-plugin-api';
 export function createEntityCardExtension<
   TInputs extends AnyExtensionInputMap,
 >(options: {
-  id: string;
+  namespace?: string;
+  name?: string;
   attachTo?: {
     id: string;
     input: string;
@@ -30,7 +31,7 @@ export function createEntityCardExtension<
   loader: (options: {
     inputs: Expand<ExtensionInputValues<TInputs>>;
   }) => Promise<JSX.Element>;
-}): Extension<{
+}): ExtensionDefinition<{
   filter?: string | undefined;
 }>;
 
@@ -38,7 +39,8 @@ export function createEntityCardExtension<
 export function createEntityContentExtension<
   TInputs extends AnyExtensionInputMap,
 >(options: {
-  id: string;
+  namespace?: string;
+  name?: string;
   attachTo?: {
     id: string;
     input: string;
@@ -54,7 +56,7 @@ export function createEntityContentExtension<
   loader: (options: {
     inputs: Expand<ExtensionInputValues<TInputs>>;
   }) => Promise<JSX.Element>;
-}): Extension<{
+}): ExtensionDefinition<{
   title: string;
   path: string;
   filter?: string | undefined;
diff --git a/plugins/catalog/api-report-alpha.md b/plugins/catalog/api-report-alpha.md
index 52afb0894a..3226d10270 100644
--- a/plugins/catalog/api-report-alpha.md
+++ b/plugins/catalog/api-report-alpha.md
@@ -7,7 +7,7 @@
 
 import { AnyExtensionInputMap } from '@backstage/frontend-plugin-api';
 import { BackstagePlugin } from '@backstage/frontend-plugin-api';
-import { Extension } from '@backstage/frontend-plugin-api';
+import { ExtensionDefinition } from '@backstage/frontend-plugin-api';
 import { ExternalRouteRef } from '@backstage/frontend-plugin-api';
 import { PortableSchema } from '@backstage/frontend-plugin-api';
 import { RouteRef } from '@backstage/frontend-plugin-api';
@@ -17,11 +17,12 @@ export function createCatalogFilterExtension<
   TInputs extends AnyExtensionInputMap,
   TConfig = never,
 >(options: {
-  id: string;
+  namespace?: string;
+  name?: string;
   inputs?: TInputs;
   configSchema?: PortableSchema<TConfig>;
   loader: (options: { config: TConfig }) => Promise<JSX.Element>;
-}): Extension<TConfig>;
+}): ExtensionDefinition<TConfig>;
 
 // @alpha (undocumented)
 const _default: BackstagePlugin<
diff --git a/plugins/explore/api-report-alpha.md b/plugins/explore/api-report-alpha.md
index 8670338f3e..4d1afa89bf 100644
--- a/plugins/explore/api-report-alpha.md
+++ b/plugins/explore/api-report-alpha.md
@@ -4,14 +4,14 @@
 
 ```ts
 import { BackstagePlugin } from '@backstage/frontend-plugin-api';
-import { Extension } from '@backstage/frontend-plugin-api';
+import { ExtensionDefinition } from '@backstage/frontend-plugin-api';
 
 // @alpha (undocumented)
 const _default: BackstagePlugin<{}, {}>;
 export default _default;
 
 // @alpha (undocumented)
-export const ExploreSearchResultListItemExtension: Extension<{
+export const ExploreSearchResultListItemExtension: ExtensionDefinition<{
   noTrack?: boolean | undefined;
 }>;
 
diff --git a/plugins/graphiql/api-report-alpha.md b/plugins/graphiql/api-report-alpha.md
index 3362cf0a59..c5895067df 100644
--- a/plugins/graphiql/api-report-alpha.md
+++ b/plugins/graphiql/api-report-alpha.md
@@ -4,20 +4,21 @@
 
 ```ts
 import { BackstagePlugin } from '@backstage/frontend-plugin-api';
-import { Extension } from '@backstage/frontend-plugin-api';
+import { ExtensionDefinition } from '@backstage/frontend-plugin-api';
 import { GraphQLEndpoint } from '@backstage/plugin-graphiql';
 import { PortableSchema } from '@backstage/frontend-plugin-api';
 import { RouteRef } from '@backstage/frontend-plugin-api';
 
 // @alpha (undocumented)
-export function createEndpointExtension<TConfig extends {}>(options: {
-  id: string;
+export function createGraphiQLEndpointExtension<TConfig extends {}>(options: {
+  namespace?: string;
+  name?: string;
   configSchema?: PortableSchema<TConfig>;
   disabled?: boolean;
   factory: (options: { config: TConfig }) => {
     endpoint: GraphQLEndpoint;
   };
-}): Extension<TConfig>;
+}): ExtensionDefinition<TConfig>;
 
 // @alpha (undocumented)
 const _default: BackstagePlugin<
@@ -29,15 +30,15 @@ const _default: BackstagePlugin<
 export default _default;
 
 // @alpha (undocumented)
-export const graphiqlBrowseApi: Extension<{}>;
+export const graphiqlBrowseApi: ExtensionDefinition<{}>;
 
 // @alpha (undocumented)
-export const GraphiqlPage: Extension<{
+export const GraphiqlPage: ExtensionDefinition<{
   path: string;
 }>;
 
 // @alpha (undocumented)
-export const graphiqlPageSidebarItem: Extension<{
+export const graphiqlPageSidebarItem: ExtensionDefinition<{
   title: string;
 }>;
 
diff --git a/plugins/search-react/api-report-alpha.md b/plugins/search-react/api-report-alpha.md
index 9c1248b536..285f1232c2 100644
--- a/plugins/search-react/api-report-alpha.md
+++ b/plugins/search-react/api-report-alpha.md
@@ -6,7 +6,7 @@
 /// <reference types="react" />
 
 import { ConfigurableExtensionDataRef } from '@backstage/frontend-plugin-api';
-import { Extension } from '@backstage/frontend-plugin-api';
+import { ExtensionDefinition } from '@backstage/frontend-plugin-api';
 import { ListItemProps } from '@material-ui/core';
 import { PortableSchema } from '@backstage/frontend-plugin-api';
 import { SearchDocument } from '@backstage/plugin-search-common';
@@ -23,7 +23,9 @@ export function createSearchResultListItemExtension<
   TConfig extends {
     noTrack?: boolean;
   },
->(options: SearchResultItemExtensionOptions<TConfig>): Extension<TConfig>;
+>(
+  options: SearchResultItemExtensionOptions<TConfig>,
+): ExtensionDefinition<TConfig>;
 
 // @alpha (undocumented)
 export type SearchResultItemExtensionComponent = <
@@ -47,7 +49,8 @@ export type SearchResultItemExtensionOptions<
     noTrack?: boolean;
   },
 > = {
-  id: string;
+  namespace?: string;
+  name?: string;
   attachTo?: {
     id: string;
     input: string;
diff --git a/plugins/search/api-report-alpha.md b/plugins/search/api-report-alpha.md
index 99f3d07b57..533734f8e9 100644
--- a/plugins/search/api-report-alpha.md
+++ b/plugins/search/api-report-alpha.md
@@ -4,7 +4,7 @@
 
 ```ts
 import { BackstagePlugin } from '@backstage/frontend-plugin-api';
-import { Extension } from '@backstage/frontend-plugin-api';
+import { ExtensionDefinition } from '@backstage/frontend-plugin-api';
 import { RouteRef } from '@backstage/frontend-plugin-api';
 
 // @alpha (undocumented)
@@ -17,15 +17,15 @@ const _default: BackstagePlugin<
 export default _default;
 
 // @alpha (undocumented)
-export const SearchApi: Extension<{}>;
+export const SearchApi: ExtensionDefinition<{}>;
 
 // @alpha (undocumented)
-export const SearchNavItem: Extension<{
+export const SearchNavItem: ExtensionDefinition<{
   title: string;
 }>;
 
 // @alpha (undocumented)
-export const SearchPage: Extension<{
+export const SearchPage: ExtensionDefinition<{
   path: string;
   noTrack: boolean;
 }>;
diff --git a/plugins/tech-radar/api-report-alpha.md b/plugins/tech-radar/api-report-alpha.md
index da8f12cf0e..bcc9142223 100644
--- a/plugins/tech-radar/api-report-alpha.md
+++ b/plugins/tech-radar/api-report-alpha.md
@@ -4,7 +4,7 @@
 
 ```ts
 import { BackstagePlugin } from '@backstage/frontend-plugin-api';
-import { Extension } from '@backstage/frontend-plugin-api';
+import { ExtensionDefinition } from '@backstage/frontend-plugin-api';
 import { RouteRef } from '@backstage/frontend-plugin-api';
 
 // @alpha (undocumented)
@@ -17,7 +17,10 @@ const _default: BackstagePlugin<
 export default _default;
 
 // @alpha (undocumented)
-export const TechRadarPage: Extension<{
+export const sampleTechRadarApi: ExtensionDefinition<{}>;
+
+// @alpha (undocumented)
+export const TechRadarPage: ExtensionDefinition<{
   height: number;
   width: number;
   title: string;
diff --git a/plugins/tech-radar/src/alpha.tsx b/plugins/tech-radar/src/alpha.tsx
index 295d084a9a..9920c767cd 100644
--- a/plugins/tech-radar/src/alpha.tsx
+++ b/plugins/tech-radar/src/alpha.tsx
@@ -47,6 +47,7 @@ export const TechRadarPage = createPageExtension({
     import('./components').then(m => <m.RadarPage {...config} />),
 });
 
+/** @alpha */
 export const sampleTechRadarApi = createApiExtension({
   factory() {
     return createApiFactory(techRadarApiRef, new SampleTechRadarApi());
diff --git a/plugins/techdocs/api-report-alpha.md b/plugins/techdocs/api-report-alpha.md
index 2b63d6e691..afc3202a43 100644
--- a/plugins/techdocs/api-report-alpha.md
+++ b/plugins/techdocs/api-report-alpha.md
@@ -4,7 +4,7 @@
 
 ```ts
 import { BackstagePlugin } from '@backstage/frontend-plugin-api';
-import { Extension } from '@backstage/frontend-plugin-api';
+import { ExtensionDefinition } from '@backstage/frontend-plugin-api';
 import { RouteRef } from '@backstage/frontend-plugin-api';
 
 // @alpha (undocumented)
@@ -23,7 +23,7 @@ const _default: BackstagePlugin<
 export default _default;
 
 // @alpha (undocumented)
-export const TechDocsSearchResultListItemExtension: Extension<{
+export const TechDocsSearchResultListItemExtension: ExtensionDefinition<{
   lineClamp: number;
   noTrack: boolean;
   asListItem: boolean;