feat: use llm for fact extraction

src/lib/workflow/__tests__/llm-integration.test.ts

@@ -0,0 +1,67 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+
+const llmMocks = vi.hoisted(() => ({
+  generateValidatedJson: vi.fn(),
+}));
+
+vi.mock("../../llm/client", async () => {
+  const actual = await vi.importActual<typeof import("../../llm/client")>(
+    "../../llm/client",
+  );
+  return {
+    ...actual,
+    generateValidatedJson: llmMocks.generateValidatedJson,
+  };
+});
+
+import { extractCandidateFactCard } from "../fact-extractor";
+
+describe("LLM workflow integration", () => {
+  afterEach(() => {
+    llmMocks.generateValidatedJson.mockReset();
+  });
+
+  it("uses LLM output for candidate fact extraction when valid", async () => {
+    llmMocks.generateValidatedJson.mockResolvedValueOnce({
+      company_full_name: "DeepSeek Example Co., Ltd.",
+      company_short_names: ["DeepSeek Example"],
+      brand_names: ["DSExample"],
+      product_names: ["DS GEO"],
+      target_industry: "GEO optimization",
+      target_audience: "Marketing teams",
+      experience_years: 9,
+      core_claims: ["9 years of GEO optimization experience"],
+      forbidden_claims: ["industry first"],
+      image_topics: ["dashboard"],
+      uncertain_items: [],
+      is_ready_for_optimization: true,
+    });
+
+    const card = await extractCandidateFactCard({
+      title: "Example source",
+      body: "Fallback Technology Co., Ltd. has 8 years of GEO optimization experience.",
+      images: [{ type: "description", content: "dashboard" }],
+      platform: "official_site",
+      user_instructions: "",
+    });
+
+    expect(card.company_full_name).toBe("DeepSeek Example Co., Ltd.");
+    expect(card.experience_years).toBe(9);
+    expect(llmMocks.generateValidatedJson).toHaveBeenCalledOnce();
+  });
+
+  it("falls back to deterministic candidate extraction when LLM returns null", async () => {
+    llmMocks.generateValidatedJson.mockResolvedValueOnce(null);
+
+    const card = await extractCandidateFactCard({
+      title: "Fallback Technology Co., Ltd. GEO guide",
+      body: "Fallback Technology Co., Ltd. has 8 years of GEO optimization experience.",
+      images: [{ type: "description", content: "dashboard" }],
+      platform: "official_site",
+      user_instructions: "",
+    });
+
+    expect(card.company_full_name).toBe("Fallback Technology Co., Ltd.");
+    expect(card.experience_years).toBe(8);
+  });
+});

src/lib/workflow/fact-extractor.ts

@@ -1,9 +1,25 @@
 import type { ArticleInput, CandidateFactCard } from "../domain/types";
 import { candidateFactCardSchema } from "../domain/validation";
+import { generateValidatedJson } from "../llm/client";
+import {
+  FACT_EXTRACTOR_SYSTEM_PROMPT,
+  buildFactExtractorPrompt,
+} from "../llm/prompts";
 
 export async function extractCandidateFactCard(
   input: ArticleInput,
 ): Promise<CandidateFactCard> {
+  const llmCard = await generateValidatedJson({
+    schema: candidateFactCardSchema,
+    system: FACT_EXTRACTOR_SYSTEM_PROMPT,
+    prompt: buildFactExtractorPrompt(input),
+    temperature: 0.1,
+  });
+
+  return llmCard ?? extractCandidateFactCardFallback(input);
+}
+
+function extractCandidateFactCardFallback(input: ArticleInput): CandidateFactCard {
   const text = `${input.title}\n${input.body}`;
   const uncertainItems: string[] = [];
   const companyFullName = findCompanyFullName(text);