diff --git a/vike-solid/renderer/+config.ts b/vike-solid/renderer/+config.ts
index a210669..e7e78d1 100644
--- a/vike-solid/renderer/+config.ts
+++ b/vike-solid/renderer/+config.ts
@@ -29,7 +29,15 @@ const toggleSsrRelatedConfig: ConfigEffect = ({
 export default {
   onRenderHtml: "import:vike-solid/renderer/onRenderHtml:onRenderHtml",
   onRenderClient: "import:vike-solid/renderer/onRenderClient:onRenderClient",
+
+  // A page can define an onBeforeRender() hook to be run on the server, which
+  // can fetch data and return it as additional page context. Typically it will
+  // return the page's root Solid component's props and additional data that can
+  // be used by the renderers.
+  // It is a cumulative config option, so a web app using vike-solid can extend
+  // this list.
   passToClient: ["pageProps", "title"],
+
   clientRouting: true,
   hydrationCanBeAborted: true,
   meta: {
@@ -46,7 +54,7 @@ export default {
       env: "server-only",
     },
     favicon: {
-      env: 'server-only'
+      env: "server-only",
     },
     lang: {
       env: "server-only",
@@ -67,7 +75,7 @@ declare global {
       Layout?: Component;
       title?: string | ((pageContext: PageContext) => string);
       description?: string;
-      favicon?: string
+      favicon?: string;
       /**
        * @default 'en'
        */
diff --git a/vike-solid/renderer/getTitle.ts b/vike-solid/renderer/getTitle.ts
index b54cfb6..1241ba7 100644
--- a/vike-solid/renderer/getTitle.ts
+++ b/vike-solid/renderer/getTitle.ts
@@ -2,21 +2,27 @@ export { getTitle };
 
 import type { PageContext } from "vike/types";
 
+/**
+ * Get the page's title if defined, either from the additional data fetched by
+ * the page's onBeforeRender() hook or from the config.
+ */
 function getTitle(pageContext: PageContext): null | string {
-  if (typeof pageContext.title === "string") {
+  if (pageContext.title !== undefined) {
     return pageContext.title;
   }
-  if (pageContext.title) {
-    throw new Error("pageContext.title should be a string");
+
+  const titleConfig = pageContext.configEntries.title?.[0];
+  if (!titleConfig) {
+    return null;
   }
-  const { title } = pageContext.config;
+  const title = titleConfig.configValue;
   if (typeof title === "string") {
     return title;
   }
   if (!title) {
     return null;
   }
-  const { configDefinedAt } = pageContext.configEntries.title![0]!;
+  const { configDefinedAt } = titleConfig;
   if (typeof title === "function") {
     const val = title(pageContext);
     if (typeof val === "string") {
diff --git a/vike-solid/renderer/types.ts b/vike-solid/renderer/types.ts
index 1573064..833fff6 100644
--- a/vike-solid/renderer/types.ts
+++ b/vike-solid/renderer/types.ts
@@ -8,8 +8,14 @@ type PageProps = Record<string, unknown>;
 declare global {
   namespace Vike {
     interface PageContext {
-      Page: Page;
-      pageProps: Record<string, unknown>;
+      // Note: Page will typically be undefined in onRenderHtml() when setting the `ssr` config flag
+      // to `false` (SPA mode).
+      Page?: Page;
+
+      /** Properties of the page's root Solid component. */
+      pageProps?: Record<string, unknown>;
+
+      /** &lt;title>${title}&lt;/title> - has precedence over the config */
       title?: string;
     }
   }