diff --git a/extensions/document-extract/document-extractor.test.ts b/extensions/document-extract/document-extractor.test.ts
index e25169a2d28e..da6555a34c28 100644
--- a/extensions/document-extract/document-extractor.test.ts
+++ b/extensions/document-extract/document-extractor.test.ts
@@ -176,6 +176,24 @@ describe("PDF document extractor", () => {
     );
   });
 
+  it("rejects selected pages outside the PDF page count before extraction", async () => {
+    pdfDocument.pageCount = 1;
+    pdfDocument.extract.mockResolvedValueOnce({ text: "", images: [] });
+    const extractor = createPdfDocumentExtractor();
+
+    await expect(extractor.extract(request({ pageNumbers: [2] }))).rejects.toThrow(
+      "No requested PDF pages exist in this 1-page document.",
+    );
+    expect(pdfDocument.extract).not.toHaveBeenCalled();
+    expect(pdfDocument.destroy).toHaveBeenCalledTimes(1);
+
+    await expect(extractor.extract(request({ pageNumbers: [] }))).resolves.toEqual({
+      text: "",
+      images: [],
+    });
+    expect(pdfDocument.destroy).toHaveBeenCalledTimes(2);
+  });
+
   it("reports image fallback failures and returns extracted text", async () => {
     const onImageExtractionError = vi.fn();
     const failure = new Error("render failed");
diff --git a/extensions/document-extract/document-extractor.ts b/extensions/document-extract/document-extractor.ts
index e2cb7dc0ac30..1c65c0072a18 100644
--- a/extensions/document-extract/document-extractor.ts
+++ b/extensions/document-extract/document-extractor.ts
@@ -70,6 +70,9 @@ async function extractPdfContent(
           .filter((p) => Number.isInteger(p) && p >= 1 && p <= pdf.pageCount)
           .slice(0, request.maxPages)
       : undefined;
+    if (request.pageNumbers?.length && pages?.length === 0) {
+      throw new Error(`No requested PDF pages exist in this ${pdf.pageCount}-page document.`);
+    }
     const pageSelection = pages ? { pages } : { maxPages: request.maxPages };
 
     const textResult = await pdf.extract({