diff --git a/apps/landing/astro.config.ts b/apps/landing/astro.config.ts
index 6671b981..20c6e51a 100644
--- a/apps/landing/astro.config.ts
+++ b/apps/landing/astro.config.ts
@@ -59,8 +59,7 @@ function createBundleReportPlugin() {
 export default defineConfig({
   adapter: cloudflare({
     imageService: { build: "compile", runtime: "cloudflare-binding" },
-    // Keep Shiki-backed Astro code rendering out of workerd's prerender path.
-    prerenderEnvironment: "node",
+    prerenderEnvironment: "workerd",
   }),
   build: {
     // Keep page CSS out of a separate render-blocking request for first-load LCP.
diff --git a/apps/landing/wrangler.toml b/apps/landing/wrangler.toml
index 62f4d573..d1990571 100644
--- a/apps/landing/wrangler.toml
+++ b/apps/landing/wrangler.toml
@@ -5,6 +5,7 @@
 name = "onequery-landing"
 main = "./src/worker.ts"
 compatibility_date = "2026-04-14"
+compatibility_flags = ["nodejs_compat"]
 logpush = true
 preview_urls = true
 routes = [{ pattern = "onequery.dev", custom_domain = true }]
diff --git a/packages/astro-agent-markdown/src/content.test.ts b/packages/astro-agent-markdown/src/content.test.ts
index c1a49c6e..b84512c3 100644
--- a/packages/astro-agent-markdown/src/content.test.ts
+++ b/packages/astro-agent-markdown/src/content.test.ts
@@ -75,6 +75,15 @@ title: Debugging production
     ).toBe("debug-production-agent-runs-with-onequery");
   });
 
+  it("does not treat a collection index route as a content entry", () => {
+    expect(
+      getContentEntryIdForMarkdownPath({
+        markdownPath: "/blog/index.md",
+        routePrefix: "/blog",
+      })
+    ).toBeUndefined();
+  });
+
   it("finds a content entry by negotiated page pathname", async () => {
     await expect(
       getContentMarkdownForPath({
diff --git a/packages/astro-agent-markdown/src/content.ts b/packages/astro-agent-markdown/src/content.ts
index 7321c40c..48b43599 100644
--- a/packages/astro-agent-markdown/src/content.ts
+++ b/packages/astro-agent-markdown/src/content.ts
@@ -97,7 +97,12 @@ export function getContentEntryIdForMarkdownPath(input: {
     return undefined;
   }
 
-  return input.markdownPath.slice(routeBase.length, -markdownSuffix.length);
+  const entryId = input.markdownPath.slice(
+    routeBase.length,
+    -markdownSuffix.length
+  );
+
+  return entryId.length > 0 ? entryId : undefined;
 }
 
 export async function getContentMarkdownForPath(input: {
diff --git a/packages/astro-agent-markdown/src/dev-middleware.test.ts b/packages/astro-agent-markdown/src/dev-middleware.test.ts
index 684ba6bc..727dbf02 100644
--- a/packages/astro-agent-markdown/src/dev-middleware.test.ts
+++ b/packages/astro-agent-markdown/src/dev-middleware.test.ts
@@ -87,6 +87,46 @@ Context, not keys.
 `);
   });
 
+  it("falls back to HTML conversion for a content collection index route", async () => {
+    const getMarkdown = vi.fn(async () => "should not read content entry");
+    const onRequest = createDevMarkdownMiddleware({
+      contentRoutes: [
+        {
+          getMarkdown,
+          routePrefix: "/blog",
+        },
+      ],
+    });
+    const next = vi.fn(
+      async () =>
+        new Response("<main><h1>Blog</h1><p>Latest updates.</p></main>", {
+          headers: { "Content-Type": "text/html; charset=utf-8" },
+        })
+    );
+
+    const response = await onRequest(
+      createContext(
+        new Request("http://localhost:4546/blog/", {
+          headers: { Accept: "text/markdown" },
+        })
+      ),
+      next as unknown as MiddlewareNext
+    );
+
+    expect(getMarkdown).not.toHaveBeenCalled();
+    expect(next).toHaveBeenCalledOnce();
+    expect(response).toBeInstanceOf(Response);
+
+    const markdownResponse = response as Response;
+    expect(markdownResponse.headers.get("Content-Type")).toBe(
+      MARKDOWN_CONTENT_TYPE
+    );
+    expect(await markdownResponse.text()).toBe(`# Blog
+
+Latest updates.
+`);
+  });
+
   it("renders HTML-derived HEAD requests with GET so token counts are available", async () => {
     const onRequest = createDevMarkdownMiddleware();
     const next = vi.fn(
diff --git a/packages/astro-agent-markdown/src/html-sidecars.test.ts b/packages/astro-agent-markdown/src/html-sidecars.test.ts
index 20f55398..c48fee70 100644
--- a/packages/astro-agent-markdown/src/html-sidecars.test.ts
+++ b/packages/astro-agent-markdown/src/html-sidecars.test.ts
@@ -67,6 +67,29 @@ describe("HTML Markdown sidecars", () => {
     expect(count).toBe(2);
   });
 
+  it("exports Markdown sidecars for HTML pages missing from the assets map", async () => {
+    const outputDir = await fs.mkdtemp(path.join(os.tmpdir(), "html-md-"));
+
+    await fs.mkdir(path.join(outputDir, "docs", "guide"), {
+      recursive: true,
+    });
+    await fs.writeFile(
+      path.join(outputDir, "docs", "guide", "index.html"),
+      "<main><h1>Guide</h1><p>Run bounded queries.</p></main>"
+    );
+
+    const count = await exportHtmlMarkdownSidecars({
+      assets: new Map(),
+      dir: pathToFileURL(`${outputDir}/`),
+      logger: createLogger(),
+    });
+
+    await expect(
+      fs.readFile(path.join(outputDir, "docs", "guide", "index.md"), "utf8")
+    ).resolves.toContain("# Guide");
+    expect(count).toBe(1);
+  });
+
   it("does not overwrite content collection Markdown sidecars", async () => {
     const outputDir = await fs.mkdtemp(path.join(os.tmpdir(), "html-md-"));
     const blogDir = path.join(outputDir, "blog/post");
diff --git a/packages/astro-agent-markdown/src/html-sidecars.ts b/packages/astro-agent-markdown/src/html-sidecars.ts
index 28e4ccec..1334378f 100644
--- a/packages/astro-agent-markdown/src/html-sidecars.ts
+++ b/packages/astro-agent-markdown/src/html-sidecars.ts
@@ -66,6 +66,33 @@ async function exportHtmlFile(input: {
   return true;
 }
 
+async function collectHtmlFiles(directory: string) {
+  const htmlPaths: string[] = [];
+
+  async function visit(currentDirectory: string) {
+    const entries = await fs.readdir(currentDirectory, { withFileTypes: true });
+
+    await Promise.all(
+      entries.map(async (entry) => {
+        const entryPath = path.join(currentDirectory, entry.name);
+
+        if (entry.isDirectory()) {
+          await visit(entryPath);
+          return;
+        }
+
+        if (entry.isFile() && entry.name.endsWith(HTML_EXTENSION)) {
+          htmlPaths.push(entryPath);
+        }
+      })
+    );
+  }
+
+  await visit(directory);
+
+  return htmlPaths;
+}
+
 export async function exportHtmlMarkdownSidecars(
   options: ExportHtmlMarkdownSidecarsOptions
 ) {
@@ -81,6 +108,12 @@ export async function exportHtmlMarkdownSidecars(
     }
   }
 
+  // Workerd prerender builds can omit static HTML pages from the hook's assets
+  // map, so scan the emitted client directory as the source of truth.
+  for (const htmlPath of await collectHtmlFiles(outputDir)) {
+    htmlAssetPaths.add(htmlPath);
+  }
+
   for (const htmlPath of htmlAssetPaths) {
     const routePath = getHtmlRoutePath(path.relative(outputDir, htmlPath));