From ff0cb407129f463cbbdc2f0d9f00b77669c492f7 Mon Sep 17 00:00:00 2001
From: Gustavo Madeira Santana <gumadeiras@gmail.com>
Date: Tue, 14 Apr 2026 13:11:47 -0400
Subject: [PATCH] QA: keep explicit Matrix model overrides lazy

Avoid loading the qa-lab runtime model-default seam when the Matrix runner was
already given both primary and alternate model refs explicitly.

Behavior stays the same, but the helper becomes easier to read and avoids an
unnecessary runtime dependency on the fully-explicit path.
---
 .../runners/contract/model-selection.test.ts    |  1 +
 .../src/runners/contract/model-selection.ts     | 17 ++++++++++++-----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/extensions/qa-matrix/src/runners/contract/model-selection.test.ts b/extensions/qa-matrix/src/runners/contract/model-selection.test.ts
index 5a49128416b..ede92b96d9c 100644
--- a/extensions/qa-matrix/src/runners/contract/model-selection.test.ts
+++ b/extensions/qa-matrix/src/runners/contract/model-selection.test.ts
@@ -45,6 +45,7 @@ describe("matrix qa model selection", () => {
       primaryModel: "custom-primary",
       alternateModel: "custom-alt",
     });
+    expect(loadQaLabRuntimeModule).not.toHaveBeenCalled();
     expect(defaultQaRuntimeModelForMode).not.toHaveBeenCalled();
   });
 });
diff --git a/extensions/qa-matrix/src/runners/contract/model-selection.ts b/extensions/qa-matrix/src/runners/contract/model-selection.ts
index 1f3d4652be8..338378d85f8 100644
--- a/extensions/qa-matrix/src/runners/contract/model-selection.ts
+++ b/extensions/qa-matrix/src/runners/contract/model-selection.ts
@@ -13,14 +13,21 @@ export function resolveMatrixQaModels(params: {
   alternateModel?: string;
 }): ResolvedMatrixQaModels {
   const providerMode = normalizeQaProviderMode(params.providerMode ?? "live-frontier");
+  const primaryModel = params.primaryModel?.trim();
+  const alternateModel = params.alternateModel?.trim();
+  if (primaryModel && alternateModel) {
+    return {
+      providerMode,
+      primaryModel,
+      alternateModel,
+    };
+  }
+
   const qaLabRuntime = loadQaLabRuntimeModule();
   return {
     providerMode,
-    primaryModel:
-      params.primaryModel?.trim() ||
-      qaLabRuntime.defaultQaRuntimeModelForMode(providerMode),
+    primaryModel: primaryModel || qaLabRuntime.defaultQaRuntimeModelForMode(providerMode),
     alternateModel:
-      params.alternateModel?.trim() ||
-      qaLabRuntime.defaultQaRuntimeModelForMode(providerMode, { alternate: true }),
+      alternateModel || qaLabRuntime.defaultQaRuntimeModelForMode(providerMode, { alternate: true }),
   };
 }