diff --git a/src/benchmarks/benchmark-config.test.ts b/src/benchmarks/benchmark-config.test.ts
index 74a1ac3..b88b874 100644
--- a/src/benchmarks/benchmark-config.test.ts
+++ b/src/benchmarks/benchmark-config.test.ts
@@ -1,4 +1,5 @@
 import { describe, expect, it } from "bun:test";
+import { spawnSync } from "node:child_process";
 
 import { assertLeft, assertRight } from "../internal/testing";
 import { parseSchema } from "../internal/zod";
@@ -12,6 +13,16 @@ import {
 } from "./benchmark-config";
 
 describe("benchmark config", () => {
+  it("loads with frozen globals in a workflow sandbox", () => {
+    const result = spawnSync(
+      process.execPath,
+      ["-e", 'Object.freeze(Error); await import("./benchmark-config.ts");'],
+      { cwd: import.meta.dirname, encoding: "utf8" }
+    );
+    expect(result.stderr).toBe("");
+    expect(result.status).toBe(0);
+  });
+
   it("keeps native configs precise while parsing them through the native schema", () => {
     const result = parseSchema(NativeBenchmarkRunConfigSchema, {
       benchmarkId: "search_hle",
diff --git a/src/benchmarks/benchmark-config.ts b/src/benchmarks/benchmark-config.ts
index 4727c98..953021c 100644
--- a/src/benchmarks/benchmark-config.ts
+++ b/src/benchmarks/benchmark-config.ts
@@ -2,10 +2,10 @@ import {
   COST_TIERS,
   IMAGE_DETAIL_VALUES,
   REASONING_EFFORTS,
+  stripVariantSuffix,
   SWITCHYARD_ALGORITHMS,
   VIDEO_PROCESSING_MODES,
 } from "../harness/constants";
-import { stripVariantSuffix } from "../harness/model";
 import { ProviderSort } from "../internal/enums";
 import type { ValueOf } from "../internal/guards";
 import { z, zDefaultedText, zInt } from "../internal/zod";
diff --git a/src/harness/constants.ts b/src/harness/constants.ts
index 355238b..9cc14f3 100644
--- a/src/harness/constants.ts
+++ b/src/harness/constants.ts
@@ -86,3 +86,8 @@ export const VIDEO_PROCESSING_MODES = [
 ] as const;
 
 export type VideoProcessingMode = ValueOf<typeof VIDEO_PROCESSING_MODES>;
+
+export function stripVariantSuffix(model: string): string {
+  const idx = model.indexOf(":");
+  return idx <= 0 ? model : model.slice(0, idx);
+}
diff --git a/src/harness/model.ts b/src/harness/model.ts
index b540a83..ac7c4f9 100644
--- a/src/harness/model.ts
+++ b/src/harness/model.ts
@@ -14,10 +14,7 @@ import type {
   ToolDefinition,
 } from "./core";
 
-export function stripVariantSuffix(model: string): string {
-  const idx = model.indexOf(":");
-  return idx <= 0 ? model : model.slice(0, idx);
-}
+export { stripVariantSuffix } from "./constants";
 
 export interface GenerateConfig {
   readonly temperature?: number;