diff --git a/CHANGELOG.md b/CHANGELOG.md
index 41e6f3ec8d2..c0b82dc96e1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- Tests: keep kitchen-sink plugin assertion fixtures on a configurable temp root so native Windows runs no longer skip full-surface diagnostic coverage.
 - Config/secrets: allow exec SecretRef ids to include `#` selectors so AWS-style `secret#json_key` ids validate consistently. (#80731) Thanks @TurboTheTurtle.
 - Tests: keep the Telegram user credential helper on platform temp and path APIs so native Windows credential export and restore commands do not write through POSIX-only paths.
 - Installer: include the optional verify phase in the progress counter so `--verify` shows `[4/4] Verifying installation` instead of `[4/3]`.
diff --git a/scripts/e2e/lib/kitchen-sink-plugin/assertions.mjs b/scripts/e2e/lib/kitchen-sink-plugin/assertions.mjs
index 71d089ba451..a147a907e72 100644
--- a/scripts/e2e/lib/kitchen-sink-plugin/assertions.mjs
+++ b/scripts/e2e/lib/kitchen-sink-plugin/assertions.mjs
@@ -1,9 +1,23 @@
 import fs from "node:fs";
+import os from "node:os";
 import path from "node:path";
 
 const command = process.argv[2];
+const scratchRoot = process.env.KITCHEN_SINK_TMP_DIR || os.tmpdir();
 
 const readJson = (file) => JSON.parse(fs.readFileSync(file, "utf8"));
+const scratchFile = (name) => path.join(scratchRoot, name);
+const normalizedPath = (filePath) => filePath.replaceAll("\\", "/");
+
+function resolveHomePath(value) {
+  if (value === "~") {
+    return process.env.HOME;
+  }
+  if (value?.startsWith("~/") || value?.startsWith("~\\")) {
+    return path.join(process.env.HOME, value.slice(2));
+  }
+  return value;
+}
 
 function expectFailure() {
   const outputFile = process.argv[3];
@@ -24,7 +38,7 @@ function expectFailure() {
 }
 
 function scanLogs() {
-  const roots = ["/tmp", path.join(process.env.HOME, ".openclaw")];
+  const roots = [scratchRoot, path.join(process.env.HOME, ".openclaw")];
   const files = [];
   const visit = (entry) => {
     if (!fs.existsSync(entry)) {
@@ -38,7 +52,7 @@ function scanLogs() {
       return;
     }
     if (/\.(?:log|jsonl)$/u.test(entry) || /openclaw-kitchen-sink-/u.test(path.basename(entry))) {
-      if (entry.includes("/.npm/_logs/")) {
+      if (normalizedPath(entry).includes("/.npm/_logs/")) {
         return;
       }
       files.push(entry);
@@ -287,9 +301,9 @@ function assertInstalled() {
   const source = process.env.KITCHEN_SINK_SOURCE;
   const surfaceMode = process.env.KITCHEN_SINK_SURFACE_MODE;
   const label = process.env.KITCHEN_SINK_LABEL;
-  const list = readJson(`/tmp/kitchen-sink-${label}-plugins.json`);
-  const inspect = readJson(`/tmp/kitchen-sink-${label}-inspect.json`);
-  const allInspect = readJson(`/tmp/kitchen-sink-${label}-inspect-all.json`);
+  const list = readJson(scratchFile(`kitchen-sink-${label}-plugins.json`));
+  const inspect = readJson(scratchFile(`kitchen-sink-${label}-inspect.json`));
+  const allInspect = readJson(scratchFile(`kitchen-sink-${label}-inspect-all.json`));
   const plugin = (list.plugins || []).find((entry) => entry.id === pluginId);
   if (!plugin) {
     throw new Error(`kitchen-sink plugin not found after install: ${pluginId}`);
@@ -429,20 +443,20 @@ function assertInstalled() {
   if (typeof record.installPath !== "string" || record.installPath.length === 0) {
     throw new Error("missing kitchen-sink install path");
   }
-  const installPath = record.installPath.replace(/^~(?=$|\/)/u, process.env.HOME);
+  const installPath = resolveHomePath(record.installPath);
   if (!fs.existsSync(installPath)) {
     throw new Error(`kitchen-sink install path missing: ${record.installPath}`);
   }
   if (source === "clawhub" && record.artifactKind === "npm-pack") {
     assertClawHubExternalInstallContract(installPath);
   }
-  fs.writeFileSync(`/tmp/kitchen-sink-${label}-install-path.txt`, installPath, "utf8");
+  fs.writeFileSync(scratchFile(`kitchen-sink-${label}-install-path.txt`), installPath, "utf8");
 }
 
 function assertRemoved() {
   const pluginId = process.env.KITCHEN_SINK_ID;
   const label = process.env.KITCHEN_SINK_LABEL;
-  const list = readJson(`/tmp/kitchen-sink-${label}-uninstalled.json`);
+  const list = readJson(scratchFile(`kitchen-sink-${label}-uninstalled.json`));
   if ((list.plugins || []).some((entry) => entry.id === pluginId)) {
     throw new Error(`kitchen-sink plugin still listed after uninstall: ${pluginId}`);
   }
@@ -467,7 +481,7 @@ function assertRemoved() {
   if (config.channels?.["kitchen-sink-channel"]) {
     throw new Error("kitchen-sink channel config still present after uninstall");
   }
-  const installPathFile = `/tmp/kitchen-sink-${label}-install-path.txt`;
+  const installPathFile = scratchFile(`kitchen-sink-${label}-install-path.txt`);
   if (fs.existsSync(installPathFile)) {
     const installPath = fs.readFileSync(installPathFile, "utf8").trim();
     if (installPath && fs.existsSync(installPath)) {
diff --git a/scripts/e2e/lib/kitchen-sink-plugin/sweep.sh b/scripts/e2e/lib/kitchen-sink-plugin/sweep.sh
index 6f45fa06173..d09d0369364 100644
--- a/scripts/e2e/lib/kitchen-sink-plugin/sweep.sh
+++ b/scripts/e2e/lib/kitchen-sink-plugin/sweep.sh
@@ -6,13 +6,14 @@ source scripts/lib/docker-e2e-logs.sh
 
 OPENCLAW_ENTRY="$(openclaw_e2e_resolve_entrypoint)"
 export OPENCLAW_ENTRY
+export KITCHEN_SINK_TMP_DIR="${KITCHEN_SINK_TMP_DIR:-/tmp}"
 
 openclaw_e2e_eval_test_state_from_b64 "${OPENCLAW_TEST_STATE_SCRIPT_B64:?missing OPENCLAW_TEST_STATE_SCRIPT_B64}"
 
 run_expect_failure() {
   local label="$1"
   shift
-  local output_file="/tmp/kitchen-sink-expected-failure-${label}.txt"
+  local output_file="${KITCHEN_SINK_TMP_DIR}/kitchen-sink-expected-failure-${label}.txt"
   set +e
   "$@" >"$output_file" 2>&1
   local status="$?"
@@ -90,9 +91,9 @@ run_success_scenario() {
   run_logged_print "kitchen-sink-install-${KITCHEN_SINK_LABEL}" node "$OPENCLAW_ENTRY" plugins install "${install_args[@]}"
   configure_kitchen_sink_runtime
   run_logged_print "kitchen-sink-enable-${KITCHEN_SINK_LABEL}" node "$OPENCLAW_ENTRY" plugins enable "$KITCHEN_SINK_ID"
-  node "$OPENCLAW_ENTRY" plugins list --json >"/tmp/kitchen-sink-${KITCHEN_SINK_LABEL}-plugins.json"
-  node "$OPENCLAW_ENTRY" plugins inspect "$KITCHEN_SINK_ID" --runtime --json >"/tmp/kitchen-sink-${KITCHEN_SINK_LABEL}-inspect.json"
-  node "$OPENCLAW_ENTRY" plugins inspect --all --runtime --json >"/tmp/kitchen-sink-${KITCHEN_SINK_LABEL}-inspect-all.json"
+  node "$OPENCLAW_ENTRY" plugins list --json >"${KITCHEN_SINK_TMP_DIR}/kitchen-sink-${KITCHEN_SINK_LABEL}-plugins.json"
+  node "$OPENCLAW_ENTRY" plugins inspect "$KITCHEN_SINK_ID" --runtime --json >"${KITCHEN_SINK_TMP_DIR}/kitchen-sink-${KITCHEN_SINK_LABEL}-inspect.json"
+  node "$OPENCLAW_ENTRY" plugins inspect --all --runtime --json >"${KITCHEN_SINK_TMP_DIR}/kitchen-sink-${KITCHEN_SINK_LABEL}-inspect-all.json"
   assert_kitchen_sink_installed
   if [ "$KITCHEN_SINK_SOURCE" = "clawhub" ]; then
     run_logged_print "kitchen-sink-uninstall-${KITCHEN_SINK_LABEL}" node "$OPENCLAW_ENTRY" plugins uninstall "$KITCHEN_SINK_SPEC" --force
@@ -100,7 +101,7 @@ run_success_scenario() {
     run_logged_print "kitchen-sink-uninstall-${KITCHEN_SINK_LABEL}" node "$OPENCLAW_ENTRY" plugins uninstall "$KITCHEN_SINK_ID" --force
   fi
   remove_kitchen_sink_channel_config
-  node "$OPENCLAW_ENTRY" plugins list --json >"/tmp/kitchen-sink-${KITCHEN_SINK_LABEL}-uninstalled.json"
+  node "$OPENCLAW_ENTRY" plugins list --json >"${KITCHEN_SINK_TMP_DIR}/kitchen-sink-${KITCHEN_SINK_LABEL}-uninstalled.json"
   assert_kitchen_sink_removed
 }
 
@@ -108,7 +109,7 @@ run_failure_scenario() {
   echo "Testing expected ${KITCHEN_SINK_LABEL} install failure from ${KITCHEN_SINK_SPEC}..."
   run_expect_failure "install-${KITCHEN_SINK_LABEL}" node "$OPENCLAW_ENTRY" plugins install "$KITCHEN_SINK_SPEC"
   remove_kitchen_sink_channel_config
-  node "$OPENCLAW_ENTRY" plugins list --json >"/tmp/kitchen-sink-${KITCHEN_SINK_LABEL}-uninstalled.json"
+  node "$OPENCLAW_ENTRY" plugins list --json >"${KITCHEN_SINK_TMP_DIR}/kitchen-sink-${KITCHEN_SINK_LABEL}-uninstalled.json"
   assert_kitchen_sink_removed
 }
 
diff --git a/test/scripts/kitchen-sink-plugin-assertions.test.ts b/test/scripts/kitchen-sink-plugin-assertions.test.ts
index cc741f8fbc1..5431e757235 100644
--- a/test/scripts/kitchen-sink-plugin-assertions.test.ts
+++ b/test/scripts/kitchen-sink-plugin-assertions.test.ts
@@ -62,10 +62,11 @@ function runAssertInstalled({
   const pluginId = "openclaw-kitchen-sink-fixture";
   const home = mkdtempSync(path.join(tmpdir(), "openclaw-kitchen-sink-home-"));
   const installPath = mkdtempSync(path.join(tmpdir(), "openclaw-kitchen-sink-install-"));
-  const pluginsJsonPath = path.join("/tmp", `kitchen-sink-${label}-plugins.json`);
-  const inspectJsonPath = path.join("/tmp", `kitchen-sink-${label}-inspect.json`);
-  const inspectAllJsonPath = path.join("/tmp", `kitchen-sink-${label}-inspect-all.json`);
-  const installPathMarker = path.join("/tmp", `kitchen-sink-${label}-install-path.txt`);
+  const scratchRoot = tmpdir();
+  const pluginsJsonPath = path.join(scratchRoot, `kitchen-sink-${label}-plugins.json`);
+  const inspectJsonPath = path.join(scratchRoot, `kitchen-sink-${label}-inspect.json`);
+  const inspectAllJsonPath = path.join(scratchRoot, `kitchen-sink-${label}-inspect-all.json`);
+  const installPathMarker = path.join(scratchRoot, `kitchen-sink-${label}-install-path.txt`);
   const installsPath = path.join(home, ".openclaw", "plugins", "installs.json");
   const spawnEnv = { ...process.env };
   delete spawnEnv.KITCHEN_SINK_REQUIRE_ALL_DIAGNOSTICS;
@@ -100,6 +101,7 @@ function runAssertInstalled({
         KITCHEN_SINK_SOURCE: "npm",
         KITCHEN_SINK_SPEC: "npm:@openclaw/kitchen-sink@latest",
         KITCHEN_SINK_SURFACE_MODE: "full",
+        KITCHEN_SINK_TMP_DIR: scratchRoot,
       },
     });
   } finally {
@@ -113,41 +115,32 @@ function runAssertInstalled({
 }
 
 describe("kitchen-sink plugin assertions", () => {
-  it.skipIf(process.platform === "win32")(
-    "fails full-surface installs when stable diagnostic canaries disappear",
-    () => {
-      const result = runAssertInstalled();
+  it("fails full-surface installs when stable diagnostic canaries disappear", () => {
+    const result = runAssertInstalled();
 
-      expect(result.status).not.toBe(0);
-      expect(`${result.stdout}\n${result.stderr}`).toContain(
-        "missing expected kitchen-sink diagnostic error",
-      );
-    },
-  );
+    expect(result.status).not.toBe(0);
+    expect(`${result.stdout}\n${result.stderr}`).toContain(
+      "missing expected kitchen-sink diagnostic error",
+    );
+  });
 
-  it.skipIf(process.platform === "win32")(
-    "accepts published full-surface installs with stable diagnostic canaries",
-    () => {
-      const result = runAssertInstalled({
-        diagnostics: diagnosticErrors(REQUIRED_FULL_DIAGNOSTIC_CANARIES),
-      });
+  it("accepts published full-surface installs with stable diagnostic canaries", () => {
+    const result = runAssertInstalled({
+      diagnostics: diagnosticErrors(REQUIRED_FULL_DIAGNOSTIC_CANARIES),
+    });
 
-      expect(result.status).toBe(0);
-    },
-  );
+    expect(result.status).toBe(0);
+  });
 
-  it.skipIf(process.platform === "win32")(
-    "keeps exhaustive diagnostic matching available for synchronized fixtures",
-    () => {
-      const result = runAssertInstalled({
-        diagnostics: diagnosticErrors(REQUIRED_FULL_DIAGNOSTIC_CANARIES),
-        env: { KITCHEN_SINK_REQUIRE_ALL_DIAGNOSTICS: "1" },
-      });
+  it("keeps exhaustive diagnostic matching available for synchronized fixtures", () => {
+    const result = runAssertInstalled({
+      diagnostics: diagnosticErrors(REQUIRED_FULL_DIAGNOSTIC_CANARIES),
+      env: { KITCHEN_SINK_REQUIRE_ALL_DIAGNOSTICS: "1" },
+    });
 
-      expect(result.status).not.toBe(0);
-      expect(`${result.stdout}\n${result.stderr}`).toContain(
-        "cli registration missing explicit commands metadata",
-      );
-    },
-  );
+    expect(result.status).not.toBe(0);
+    expect(`${result.stdout}\n${result.stderr}`).toContain(
+      "cli registration missing explicit commands metadata",
+    );
+  });
 });