diff --git a/extensions/qa-matrix/src/runners/contract/runtime.test.ts b/extensions/qa-matrix/src/runners/contract/runtime.test.ts
index 5a88a2eb42a1..f98cde6cf779 100644
--- a/extensions/qa-matrix/src/runners/contract/runtime.test.ts
+++ b/extensions/qa-matrix/src/runners/contract/runtime.test.ts
@@ -1,4 +1,5 @@
 // Qa Matrix tests cover runtime plugin behavior.
+import path from "node:path";
 import type { OpenClawConfig } from "openclaw/plugin-sdk/config-contracts";
 import { MAX_TIMER_TIMEOUT_MS } from "openclaw/plugin-sdk/number-runtime";
 import { renderQaMarkdownReport } from "openclaw/plugin-sdk/qa-runtime";
@@ -77,6 +78,19 @@ function buildMatrixQaSummaryInput(
 }
 
 describe("matrix live qa runtime", () => {
+  it("uses unique default artifact directories", () => {
+    const repoRoot = "/repo";
+    const firstOutputDir = liveTesting.resolveMatrixQaOutputDir({ repoRoot });
+    const secondOutputDir = liveTesting.resolveMatrixQaOutputDir({ repoRoot });
+
+    expect(path.dirname(firstOutputDir)).toBe(path.join(repoRoot, ".artifacts", "qa-e2e"));
+    expect(path.basename(firstOutputDir)).toMatch(/^matrix-[a-z0-9]+-[a-f0-9]{8}$/u);
+    expect(secondOutputDir).not.toBe(firstOutputDir);
+    expect(
+      liveTesting.resolveMatrixQaOutputDir({ outputDir: ".artifacts/custom", repoRoot }),
+    ).toBe(".artifacts/custom");
+  });
+
   it("prints Matrix QA progress by default for non-interactive runs", () => {
     const previous = process.env.OPENCLAW_QA_MATRIX_PROGRESS;
     delete process.env.OPENCLAW_QA_MATRIX_PROGRESS;
diff --git a/extensions/qa-matrix/src/runners/contract/runtime.ts b/extensions/qa-matrix/src/runners/contract/runtime.ts
index 367b04d12706..74caf221d334 100644
--- a/extensions/qa-matrix/src/runners/contract/runtime.ts
+++ b/extensions/qa-matrix/src/runners/contract/runtime.ts
@@ -29,6 +29,7 @@ import {
 } from "../../substrate/config.js";
 import type { MatrixQaObservedEvent } from "../../substrate/events.js";
 import { startMatrixQaHarness } from "../../substrate/harness.runtime.js";
+import { createLiveTransportQaRunId } from "../../shared/live-transport-artifacts.js";
 import { resolveMatrixQaModels, type ResolvedMatrixQaModels } from "./model-selection.js";
 import type { MatrixQaSyncStreams } from "./scenario-runtime-shared.js";
 import {
@@ -623,6 +624,13 @@ function isMatrixQaStaleConfigPatchError(error: unknown) {
   return formatErrorMessage(error).toLowerCase().includes("config changed since last load");
 }
 
+function resolveMatrixQaOutputDir(params: { outputDir?: string; repoRoot: string }) {
+  return (
+    params.outputDir ??
+    path.join(params.repoRoot, ".artifacts", "qa-e2e", `matrix-${createLiveTransportQaRunId()}`)
+  );
+}
+
 async function startMatrixQaLiveLaneGateway(params: {
   repoRoot: string;
   transport: {
@@ -657,9 +665,7 @@ export async function runMatrixQaLive(params: {
   alternateModel?: string;
 }): Promise<MatrixQaRunResult> {
   const repoRoot = path.resolve(params.repoRoot ?? process.cwd());
-  const outputDir =
-    params.outputDir ??
-    path.join(repoRoot, ".artifacts", "qa-e2e", `matrix-${Date.now().toString(36)}`);
+  const outputDir = resolveMatrixQaOutputDir({ outputDir: params.outputDir, repoRoot });
   await fs.mkdir(outputDir, { recursive: true });
 
   const defaultModels = resolveMatrixQaModels({
@@ -1276,6 +1282,7 @@ export const testing = {
   isMatrixAccountReady,
   patchMatrixQaGatewayConfig,
   remainingMatrixQaRunMs,
+  resolveMatrixQaOutputDir,
   resolveMatrixQaCanaryTimeoutMs,
   resolveMatrixQaModels,
   shouldWriteMatrixQaProgress,
diff --git a/extensions/qa-matrix/src/shared/live-transport-artifacts.ts b/extensions/qa-matrix/src/shared/live-transport-artifacts.ts
new file mode 100644
index 000000000000..27499821755c
--- /dev/null
+++ b/extensions/qa-matrix/src/shared/live-transport-artifacts.ts
@@ -0,0 +1,6 @@
+// Qa Matrix plugin module implements live transport artifact behavior.
+import { randomUUID } from "node:crypto";
+
+export function createLiveTransportQaRunId() {
+  return `${Date.now().toString(36)}-${randomUUID().slice(0, 8)}`;
+}
diff --git a/extensions/qa-matrix/src/shared/live-transport-cli.runtime.test.ts b/extensions/qa-matrix/src/shared/live-transport-cli.runtime.test.ts
index 887a46a0c0be..0caae15ea424 100644
--- a/extensions/qa-matrix/src/shared/live-transport-cli.runtime.test.ts
+++ b/extensions/qa-matrix/src/shared/live-transport-cli.runtime.test.ts
@@ -4,6 +4,7 @@ import os from "node:os";
 import path from "node:path";
 import { startLiveTransportQaOutputTee } from "openclaw/plugin-sdk/qa-runtime";
 import { afterEach, describe, expect, it } from "vitest";
+import { resolveLiveTransportQaRunOptions } from "./live-transport-cli.runtime.js";
 
 const tmpDirs: string[] = [];
 
@@ -12,6 +13,22 @@ describe("live transport CLI runtime", () => {
     await Promise.all(tmpDirs.splice(0).map((dir) => rm(dir, { recursive: true, force: true })));
   });
 
+  it("uses unique default output dirs for CLI runs", () => {
+    const repoRoot = "/repo";
+    const firstOutputDir = resolveLiveTransportQaRunOptions({ repoRoot }).outputDir;
+    const secondOutputDir = resolveLiveTransportQaRunOptions({ repoRoot }).outputDir;
+
+    expect(path.dirname(firstOutputDir)).toBe(path.join(repoRoot, ".artifacts", "qa-e2e"));
+    expect(path.basename(firstOutputDir)).toMatch(/^matrix-[a-z0-9]+-[a-f0-9]{8}$/u);
+    expect(secondOutputDir).not.toBe(firstOutputDir);
+    expect(
+      resolveLiveTransportQaRunOptions({
+        repoRoot,
+        outputDir: ".artifacts/custom",
+      }).outputDir,
+    ).toBe(path.join(repoRoot, ".artifacts/custom"));
+  });
+
   it("tees stdout and stderr into an output artifact", async () => {
     const outputDir = await mkdtemp(path.join(os.tmpdir(), "matrix-qa-output-"));
     tmpDirs.push(outputDir);
diff --git a/extensions/qa-matrix/src/shared/live-transport-cli.runtime.ts b/extensions/qa-matrix/src/shared/live-transport-cli.runtime.ts
index ee2c1e52611f..0fef6c72d6bd 100644
--- a/extensions/qa-matrix/src/shared/live-transport-cli.runtime.ts
+++ b/extensions/qa-matrix/src/shared/live-transport-cli.runtime.ts
@@ -3,6 +3,7 @@ import path from "node:path";
 import { resolveRepoRelativeOutputDir } from "../cli-paths.js";
 import type { QaProviderMode } from "../run-config.js";
 import { normalizeQaProviderMode } from "../run-config.js";
+import { createLiveTransportQaRunId } from "./live-transport-artifacts.js";
 import type { LiveTransportQaCommandOptions } from "./live-transport-cli.js";
 
 export function resolveLiveTransportQaRunOptions(
@@ -15,7 +16,7 @@ export function resolveLiveTransportQaRunOptions(
   const repoRoot = path.resolve(opts.repoRoot ?? process.cwd());
   const outputDir =
     resolveRepoRelativeOutputDir(repoRoot, opts.outputDir) ??
-    path.join(repoRoot, ".artifacts", "qa-e2e", `matrix-${Date.now().toString(36)}`);
+    path.join(repoRoot, ".artifacts", "qa-e2e", `matrix-${createLiveTransportQaRunId()}`);
   return {
     repoRoot,
     outputDir,