Use explicit model ids in e2e tests

Author: ishulgin

src/__tests__/CodexACPAgent/e2e/acp-e2e-test-utils.ts

@@ -9,8 +9,10 @@ export {
     type PermissionResponder,
 } from "./permission-responders";
 export {
+    DEFAULT_TEST_MODEL_ID,
     type SpawnedAgentFixture,
     type TestSkill,
+    OTHER_TEST_MODEL_ID,
 } from "./spawned-agent-fixture";
 
 export const RUN_E2E_TESTS = process.env["RUN_E2E_TESTS"] === "true";

src/__tests__/CodexACPAgent/e2e/acp-e2e.test.ts

@@ -3,7 +3,9 @@ import {AgentMode} from "../../../AgentMode";
 import {
     createAuthenticatedFixture,
     createGatewayFixture,
+    DEFAULT_TEST_MODEL_ID,
     describeE2E,
+    OTHER_TEST_MODEL_ID,
     requireLiveApiKey,
     type SpawnedAgentFixture,
 } from "./acp-e2e-test-utils";
@@ -44,20 +46,13 @@ describeE2E("E2E tests", () => {
             throw new Error("Agent did not return initial model state.");
         }
         expect(models.availableModels.length).toBeGreaterThan(0);
-
-        const selectedModelId =
-            models.availableModels.find((model) => model.modelId !== models.currentModelId)?.modelId
-            ?? models.currentModelId
-            ?? models.availableModels[0]?.modelId;
-        if (!selectedModelId) {
-            throw new Error("No available models returned by ACP server.");
-        }
+        expect(models.currentModelId).toBe(DEFAULT_TEST_MODEL_ID.toString());
 
         await fixture.connection.unstable_setSessionModel({
             sessionId: session.sessionId,
-            modelId: selectedModelId,
+            modelId: OTHER_TEST_MODEL_ID.toString(),
         });
-        await fixture.expectStatus(session.sessionId, {Model: selectedModelId});
+        await fixture.expectStatus(session.sessionId, {Model: OTHER_TEST_MODEL_ID});
     });
 
     it("changes session mode via setSessionMode and reflects it in /status", async () => {

src/__tests__/CodexACPAgent/e2e/spawned-agent-fixture.ts

@@ -5,9 +5,13 @@ import os from "node:os";
 import path from "node:path";
 import {Readable, Writable} from "node:stream";
 import {expect, vi} from "vitest";
+import {ModelId} from "../../../ModelId";
 import {removeDirectoryWithRetry, writeCodexHomeConfig} from "../../acp-test-utils";
 import type {PermissionResponder} from "./permission-responders";
 
+export const DEFAULT_TEST_MODEL_ID = ModelId.create("gpt-5.2", "none");
+export const OTHER_TEST_MODEL_ID = ModelId.create("gpt-5.3-codex", "low");
+
 export interface TestSkill {
     readonly name: string;
     readonly description: string;
@@ -39,8 +43,8 @@ export function createSpawnedAgentFixture(
 ): SpawnedAgentFixture {
     const paths = RuntimePaths.createTemporary();
     writeCodexHomeConfig(paths.codexHome, {
-        model: "gpt-5.2",
-        model_reasoning_effort: "none",
+        model: DEFAULT_TEST_MODEL_ID.model,
+        model_reasoning_effort: DEFAULT_TEST_MODEL_ID.effort,
         web_search: "disabled",
     });