diff --git a/app/core/src/test/java/stirling/software/SPDF/model/api/converters/ConvertPDFToMarkdownTest.java b/app/core/src/test/java/stirling/software/SPDF/model/api/converters/ConvertPDFToMarkdownTest.java
new file mode 100644
index 000000000..606c9fe7a
--- /dev/null
+++ b/app/core/src/test/java/stirling/software/SPDF/model/api/converters/ConvertPDFToMarkdownTest.java
@@ -0,0 +1,107 @@
+package stirling.software.SPDF.model.api.converters;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.*;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.multipart;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
+
+import java.nio.charset.StandardCharsets;
+
+import org.junit.jupiter.api.Test;
+import org.mockito.ArgumentCaptor;
+import org.mockito.MockedConstruction;
+import org.mockito.Mockito;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.mock.web.MockMultipartFile;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.RestControllerAdvice;
+import org.springframework.web.multipart.MultipartFile;
+
+import stirling.software.common.util.PDFToFile;
+
+class ConvertPDFToMarkdownTest {
+
+    private MockMvc mockMvc() {
+        return MockMvcBuilders.standaloneSetup(new ConvertPDFToMarkdown())
+                .setControllerAdvice(new GlobalErrorHandler())
+                .build();
+    }
+
+    @RestControllerAdvice
+    static class GlobalErrorHandler {
+        @ExceptionHandler(Exception.class)
+        ResponseEntity<byte[]> handle(Exception ex) {
+            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(new byte[0]);
+        }
+    }
+
+    @Test
+    void pdf_to_markdown_returns_markdown_bytes() throws Exception {
+        byte[] md = "# heading\n\ncontent\n".getBytes(StandardCharsets.UTF_8);
+
+        try (MockedConstruction<PDFToFile> construction =
+                Mockito.mockConstruction(
+                        PDFToFile.class,
+                        (mock, ctx) -> {
+                            when(mock.processPdfToMarkdown(any(MultipartFile.class)))
+                                    .thenAnswer(
+                                            inv ->
+                                                    ResponseEntity.ok()
+                                                            .header("Content-Type", "text/markdown")
+                                                            .body(md));
+                        })) {
+
+            MockMvc mvc = mockMvc();
+
+            MockMultipartFile file =
+                    new MockMultipartFile(
+                            "fileInput", // muss zum Feldnamen in PDFFile passen
+                            "input.pdf",
+                            "application/pdf",
+                            new byte[] {1, 2, 3});
+
+            mvc.perform(multipart("/api/v1/convert/pdf/markdown").file(file))
+                    .andExpect(status().isOk())
+                    .andExpect(header().string("Content-Type", "text/markdown"))
+                    .andExpect(content().bytes(md));
+
+            // Verifizieren, dass genau eine Instanz erzeugt wurde
+            assert construction.constructed().size() == 1;
+
+            // und dass das hochgeladene File an processPdfToMarkdown() durchgereicht wurde
+            PDFToFile created = construction.constructed().get(0);
+            ArgumentCaptor<MultipartFile> captor = ArgumentCaptor.forClass(MultipartFile.class);
+            verify(created, times(1)).processPdfToMarkdown(captor.capture());
+            MultipartFile passed = captor.getValue();
+            // minimal plausi
+            org.junit.jupiter.api.Assertions.assertEquals(
+                    "input.pdf", passed.getOriginalFilename());
+            org.junit.jupiter.api.Assertions.assertEquals(
+                    "application/pdf", passed.getContentType());
+        }
+    }
+
+    @Test
+    void pdf_to_markdown_when_service_throws_returns_500() throws Exception {
+        try (MockedConstruction<PDFToFile> ignored =
+                Mockito.mockConstruction(
+                        PDFToFile.class,
+                        (mock, ctx) -> {
+                            when(mock.processPdfToMarkdown(any(MultipartFile.class)))
+                                    .thenThrow(new RuntimeException("boom"));
+                        })) {
+
+            MockMvc mvc = mockMvc();
+
+            MockMultipartFile file =
+                    new MockMultipartFile(
+                            "fileInput", "x.pdf", "application/pdf", new byte[] {0x01});
+
+            mvc.perform(multipart("/api/v1/convert/pdf/markdown").file(file))
+                    .andExpect(status().isInternalServerError());
+        }
+    }
+}