diff --git a/scripts/bench-cli-startup.ts b/scripts/bench-cli-startup.ts
index d763a81d5fc2..11fd4781d731 100644
--- a/scripts/bench-cli-startup.ts
+++ b/scripts/bench-cli-startup.ts
@@ -838,6 +838,8 @@ export function collectFailedSamples(result: SuiteResult): string[] {
         failures.push(`${label}: exited via signal ${sample.signal}`);
       } else if (!expectedExitCodes.has(sample.exitCode ?? -1)) {
         failures.push(`${label}: exited with code ${String(sample.exitCode)}`);
+      } else if (sample.maxRssMb === null) {
+        failures.push(`${label}: did not report max RSS`);
       } else if (sample.exitCode !== 0) {
         const output = `${sample.stdoutTail ?? ""}\n${sample.stderrTail ?? ""}`;
         const missing = (commandCase.expectedNonzeroOutputIncludes ?? []).filter(
diff --git a/scripts/test-cli-startup-bench-budget.mjs b/scripts/test-cli-startup-bench-budget.mjs
index 035b305deb9a..e396d9c58ddb 100644
--- a/scripts/test-cli-startup-bench-budget.mjs
+++ b/scripts/test-cli-startup-bench-budget.mjs
@@ -174,6 +174,10 @@ for (const currentCase of currentCases.values()) {
     console.error(`[test-cli-startup-bench-budget] ${currentCase.name} timed out.`);
     failed = true;
   }
+  if (samples.some((sample) => !Number.isFinite(sample.maxRssMb))) {
+    console.error(`[test-cli-startup-bench-budget] ${currentCase.name} did not report max RSS.`);
+    failed = true;
+  }
 }
 
 if (!opts.skipBaseline) {
diff --git a/test/scripts/bench-cli-startup.test.ts b/test/scripts/bench-cli-startup.test.ts
index fdc551c38311..d073a98e10d0 100644
--- a/test/scripts/bench-cli-startup.test.ts
+++ b/test/scripts/bench-cli-startup.test.ts
@@ -91,6 +91,38 @@ describe("bench-cli-startup", () => {
     ]);
   });
 
+  it("fails reports with samples that did not report RSS", () => {
+    expect(
+      testing.collectFailedSamples({
+        entry: "openclaw.mjs",
+        cases: [
+          {
+            id: "version",
+            name: "--version",
+            args: ["--version"],
+            contract: null,
+            samples: [
+              {
+                ms: 10,
+                firstOutputMs: 5,
+                maxRssMb: null,
+                exitCode: 0,
+                signal: null,
+              },
+            ],
+            summary: {
+              sampleCount: 1,
+              durationMs: { avg: 10, p50: 10, p95: 10, min: 10, max: 10 },
+              firstOutputMs: { avg: 5, p50: 5, p95: 5, min: 5, max: 5 },
+              maxRssMb: null,
+              exitSummary: "code:0x1",
+            },
+          },
+        ],
+      }),
+    ).toEqual(["openclaw.mjs version sample 1: did not report max RSS"]);
+  });
+
   it("allows declared nonzero exit codes for clean-state probes", () => {
     const sample = {
       ms: 10,
diff --git a/test/scripts/cli-startup-bench-spawner.test.ts b/test/scripts/cli-startup-bench-spawner.test.ts
index b9a5e4889fc7..23545a8dbfb5 100644
--- a/test/scripts/cli-startup-bench-spawner.test.ts
+++ b/test/scripts/cli-startup-bench-spawner.test.ts
@@ -270,6 +270,46 @@ describe("CLI startup benchmark script spawners", () => {
     }
   });
 
+  it("fails reused reports with missing RSS samples", () => {
+    const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), "openclaw-bench-budget-rss-test-"));
+    try {
+      const baselinePath = path.join(tmpDir, "baseline.json");
+      const reportPath = path.join(tmpDir, "current.json");
+      const missingRssCase = {
+        id: "version",
+        name: "--version",
+        samples: [{ ms: 10, firstOutputMs: 5, maxRssMb: null, exitCode: 0, signal: null }],
+        summary: {
+          durationMs: { avg: 10, p50: 10, p95: 10, min: 10, max: 10 },
+          firstOutputMs: { avg: 5, p50: 5, p95: 5, min: 5, max: 5 },
+          maxRssMb: null,
+        },
+      };
+      fs.writeFileSync(baselinePath, JSON.stringify({ primary: { cases: [missingRssCase] } }));
+      fs.writeFileSync(reportPath, JSON.stringify({ primary: { cases: [missingRssCase] } }));
+
+      const result = spawnSync(
+        process.execPath,
+        [
+          "scripts/test-cli-startup-bench-budget.mjs",
+          "--baseline",
+          baselinePath,
+          "--report",
+          reportPath,
+          "--skip-baseline",
+        ],
+        { cwd: process.cwd(), encoding: "utf8" },
+      );
+
+      expect(result.status).toBe(1);
+      expect(result.stderr).toContain(
+        "[test-cli-startup-bench-budget] --version did not report max RSS.",
+      );
+    } finally {
+      fs.rmSync(tmpDir, { recursive: true, force: true });
+    }
+  });
+
   it("rejects malformed startup budget env vars before reading reports", () => {
     const result = spawnSync(process.execPath, ["scripts/test-cli-startup-bench-budget.mjs"], {
       cwd: process.cwd(),