feat(models): improve OpenRouter free scan

src/agents/model-scan.test.ts

@@ -0,0 +1,84 @@
+import { describe, expect, it } from "vitest";
+
+import { scanOpenRouterModels } from "./model-scan.js";
+
+function createFetchFixture(payload: unknown): typeof fetch {
+  return async () =>
+    new Response(JSON.stringify(payload), {
+      status: 200,
+      headers: { "content-type": "application/json" },
+    });
+}
+
+describe("scanOpenRouterModels", () => {
+  it("lists free models without probing", async () => {
+    const fetchImpl = createFetchFixture({
+      data: [
+        {
+          id: "acme/free-by-pricing",
+          name: "Free By Pricing",
+          context_length: 16_384,
+          max_completion_tokens: 1024,
+          supported_parameters: ["tools", "tool_choice", "temperature"],
+          modality: "text",
+          pricing: { prompt: "0", completion: "0", request: "0", image: "0" },
+          created_at: 1_700_000_000,
+        },
+        {
+          id: "acme/free-by-suffix:free",
+          name: "Free By Suffix",
+          context_length: 8_192,
+          supported_parameters: [],
+          modality: "text",
+          pricing: { prompt: "0", completion: "0" },
+        },
+        {
+          id: "acme/paid",
+          name: "Paid",
+          context_length: 4_096,
+          supported_parameters: ["tools"],
+          modality: "text",
+          pricing: { prompt: "0.000001", completion: "0.000002" },
+        },
+      ],
+    });
+
+    const results = await scanOpenRouterModels({
+      fetchImpl,
+      probe: false,
+    });
+
+    expect(results.map((entry) => entry.id)).toEqual([
+      "acme/free-by-pricing",
+      "acme/free-by-suffix:free",
+    ]);
+
+    const byPricing = results[0]!;
+    expect(byPricing.supportsToolsMeta).toBe(true);
+    expect(byPricing.supportedParametersCount).toBe(3);
+    expect(byPricing.isFree).toBe(true);
+    expect(byPricing.tool.skipped).toBe(true);
+    expect(byPricing.image.skipped).toBe(true);
+  });
+
+  it("requires an API key when probing", async () => {
+    const fetchImpl = createFetchFixture({ data: [] });
+    const previousKey = process.env.OPENROUTER_API_KEY;
+    try {
+      delete process.env.OPENROUTER_API_KEY;
+      await expect(
+        scanOpenRouterModels({
+          fetchImpl,
+          probe: true,
+          apiKey: "",
+        }),
+      ).rejects.toThrow(/Missing OpenRouter API key/);
+    } finally {
+      if (previousKey === undefined) {
+        delete process.env.OPENROUTER_API_KEY;
+      } else {
+        process.env.OPENROUTER_API_KEY = previousKey;
+      }
+    }
+  });
+});