fix: respect session model override in agent runtime (#14783) (#14983)

Merged via /review-pr -> /prepare-pr -> /merge-pr.

Prepared head SHA: ec47d1a7bf
Co-authored-by: shtse8 <8020099+shtse8@users.noreply.github.com>
Co-authored-by: gumadeiras <5599352+gumadeiras@users.noreply.github.com>
Reviewed-by: @gumadeiras

src/cron/isolated-agent/session.test.ts

@@ -0,0 +1,73 @@
+import { describe, expect, it, vi } from "vitest";
+import type { OpenClawConfig } from "../../config/config.js";
+
+vi.mock("../../config/sessions.js", () => ({
+  loadSessionStore: vi.fn(),
+  resolveStorePath: vi.fn().mockReturnValue("/tmp/test-store.json"),
+}));
+
+import { loadSessionStore } from "../../config/sessions.js";
+import { resolveCronSession } from "./session.js";
+
+describe("resolveCronSession", () => {
+  it("preserves modelOverride and providerOverride from existing session entry", () => {
+    vi.mocked(loadSessionStore).mockReturnValue({
+      "agent:main:cron:test-job": {
+        sessionId: "old-session-id",
+        updatedAt: 1000,
+        modelOverride: "deepseek-v3-4bit-mlx",
+        providerOverride: "inferencer",
+        thinkingLevel: "high",
+        model: "k2p5",
+      },
+    });
+
+    const result = resolveCronSession({
+      cfg: {} as OpenClawConfig,
+      sessionKey: "agent:main:cron:test-job",
+      agentId: "main",
+      nowMs: Date.now(),
+    });
+
+    expect(result.sessionEntry.modelOverride).toBe("deepseek-v3-4bit-mlx");
+    expect(result.sessionEntry.providerOverride).toBe("inferencer");
+    expect(result.sessionEntry.thinkingLevel).toBe("high");
+    // The model field (last-used model) should also be preserved
+    expect(result.sessionEntry.model).toBe("k2p5");
+  });
+
+  it("handles missing modelOverride gracefully", () => {
+    vi.mocked(loadSessionStore).mockReturnValue({
+      "agent:main:cron:test-job": {
+        sessionId: "old-session-id",
+        updatedAt: 1000,
+        model: "claude-opus-4-5",
+      },
+    });
+
+    const result = resolveCronSession({
+      cfg: {} as OpenClawConfig,
+      sessionKey: "agent:main:cron:test-job",
+      agentId: "main",
+      nowMs: Date.now(),
+    });
+
+    expect(result.sessionEntry.modelOverride).toBeUndefined();
+    expect(result.sessionEntry.providerOverride).toBeUndefined();
+  });
+
+  it("handles no existing session entry", () => {
+    vi.mocked(loadSessionStore).mockReturnValue({});
+
+    const result = resolveCronSession({
+      cfg: {} as OpenClawConfig,
+      sessionKey: "agent:main:cron:new-job",
+      agentId: "main",
+      nowMs: Date.now(),
+    });
+
+    expect(result.sessionEntry.modelOverride).toBeUndefined();
+    expect(result.sessionEntry.providerOverride).toBeUndefined();
+    expect(result.sessionEntry.model).toBeUndefined();
+  });
+});