fix: default custom provider model fields

src/config/model-alias-defaults.test.ts

@@ -1,4 +1,5 @@
 import { describe, expect, it } from "vitest";
+import { DEFAULT_CONTEXT_TOKENS } from "../agents/defaults.js";
 import { applyModelDefaults } from "./defaults.js";
 import type { ClawdbotConfig } from "./types.js";
 
@@ -55,4 +56,28 @@ describe("applyModelDefaults", () => {
       "gemini-flash",
     );
   });
+
+  it("fills missing model provider defaults", () => {
+    const cfg = {
+      models: {
+        providers: {
+          myproxy: {
+            baseUrl: "https://proxy.example/v1",
+            apiKey: "sk-test",
+            api: "openai-completions",
+            models: [{ id: "gpt-5.2", name: "GPT-5.2" }],
+          },
+        },
+      },
+    } satisfies ClawdbotConfig;
+
+    const next = applyModelDefaults(cfg);
+    const model = next.models?.providers?.myproxy?.models?.[0];
+
+    expect(model?.reasoning).toBe(false);
+    expect(model?.input).toEqual(["text"]);
+    expect(model?.cost).toEqual({ input: 0, output: 0, cacheRead: 0, cacheWrite: 0 });
+    expect(model?.contextWindow).toBe(DEFAULT_CONTEXT_TOKENS);
+    expect(model?.maxTokens).toBe(8192);
+  });
 });