diff --git a/doc/execution-semantics.md b/doc/execution-semantics.md
index 58248674d5..fdc71cad49 100644
--- a/doc/execution-semantics.md
+++ b/doc/execution-semantics.md
@@ -1207,7 +1207,9 @@ that the task is complete.
 For an explicit file output in the current request, an empty report, a
 verification-only reference, or an unregistered URL cannot satisfy delivery.
 The report must cite a task-scoped attachment or a registered accessible work
-product. Reading or reviewing an existing file for an inline answer does not
+product with a published URL. A `workspace_file` locator alone is not delivery
+evidence: it neither verifies the file nor preserves its bytes after cleanup.
+Reading or reviewing an existing file for an inline answer does not
 require uploading that input. Ambiguous prose remains subject to the runner's
 completion contract; the server's explicit-output check is deliberately narrow.
 
diff --git a/server/src/services/native-runtime/native-deliverable-feedback.ts b/server/src/services/native-runtime/native-deliverable-feedback.ts
index 998bdb605e..64f8a516c1 100644
--- a/server/src/services/native-runtime/native-deliverable-feedback.ts
+++ b/server/src/services/native-runtime/native-deliverable-feedback.ts
@@ -84,9 +84,10 @@ export async function validateNativeDeliverableEvidence(
     )) : [];
     const accessibleProduct = products.some(product => {
       if (["failed", "cancelled", "archived"].includes(product.status)) return false;
-      const resource = product.metadata?.resourceRef as { kind?: unknown; path?: unknown } | undefined;
-      const accessible = (typeof product.url === "string" && /^https?:\/\//iu.test(product.url)) ||
-        (resource?.kind === "workspace_file" && typeof resource.path === "string" && resource.path.length > 0);
+      // A workspace_file resource is only a locator: registration neither checks
+      // its current bytes nor keeps them alive after workspace cleanup. Requested
+      // files need a published URL or the verified attachment receipt above.
+      const accessible = typeof product.url === "string" && /^https?:\/\//iu.test(product.url);
       return accessible && [product.url, `work_product:${product.id}`, `work-product:${product.id}`, `artifact:${product.id}`]
         .some(ref => typeof ref === "string" && refs.has(ref));
     });
diff --git a/server/src/services/native-runtime/native-runner-file-handoff.test.ts b/server/src/services/native-runtime/native-runner-file-handoff.test.ts
index 8c2d7c02f6..212756c819 100644
--- a/server/src/services/native-runtime/native-runner-file-handoff.test.ts
+++ b/server/src/services/native-runtime/native-runner-file-handoff.test.ts
@@ -226,9 +226,11 @@ describe("native runner file handoff", () => {
         await expect(nativeCompletionFeedback(db, runId, doneReport([ref])))
           .resolves.toContain("Completion report accepted");
       }
-      await db.update(issueWorkProducts).set({ url: null, metadata: { resourceRef: { kind: "workspace_file", path: "report.pdf" } } }).where(eq(issueWorkProducts.id, product.id));
+      // Metadata can name a nonexistent or cleaned-up workspace file; it is not a download.
+      await db.update(issueWorkProducts).set({ url: null, metadata: { resourceRef: { kind: "workspace_file", path: "missing-report.pdf" } } }).where(eq(issueWorkProducts.id, product.id));
       await expect(nativeCompletionFeedback(db, runId, doneReport([`work_product:${product.id}`])))
-        .resolves.toContain("Completion report accepted");
+        .rejects.toThrow("requested file has no accessible delivery evidence");
+      await db.update(issueWorkProducts).set({ url: product.url }).where(eq(issueWorkProducts.id, product.id));
       await db.update(issueWorkProducts).set({ status: "failed" }).where(eq(issueWorkProducts.id, product.id));
       await expect(nativeCompletionFeedback(db, runId, doneReport([`work_product:${product.id}`])))
         .rejects.toThrow("requested file has no accessible delivery evidence");