fix(engine): add the missing documentation_url snake_case alias, derive the urlFields pairing test

packages/loopover-engine/src/review/content-lane/content-repo-spec.ts

@@ -102,6 +102,7 @@ export const AWESOME_CLAUDE_CONTENT_SPEC: ContentRepoSpec = {
     "sourceUrl",
     "websiteUrl",
     "docs_url",
+    "documentation_url",
     "download_url",
     "github_url",
     "package_url",
@@ -141,6 +142,7 @@ export const AWESOME_CLAUDE_CONTENT_SPEC: ContentRepoSpec = {
     "repository_url",
     "source_url",
     "website_url",
+    "documentation_url",
   ],
   sourceUrlListFields: new Set(["sourceUrls", "retrievalSources"]),
   // snake_case aliases match urlFields / sourceUrlFields (#7446): without them, a site-relative

packages/loopover-engine/test/content-repo-spec.test.ts

@@ -0,0 +1,22 @@
+import { test } from "node:test";
+import assert from "node:assert/strict";
+
+import { AWESOME_CLAUDE_CONTENT_SPEC } from "../dist/review/content-lane/content-repo-spec.js";
+
+// Mirrors the derived pairing assertion at test/unit/content-lane-duplicates.test.ts (protectedFrontmatterFields)
+// and test/unit/content-lane-source-evidence.test.ts (urlFields): a hand-enumerated alias list can't catch the
+// next camelCase URL field added to the spec without a matching snake_case alias — a derived walk can (#9992).
+test("every camelCase urlFields member has its snake_case alias present in both urlFields and sourceUrlFields", () => {
+  const toSnakeCase = (field: string): string => field.replace(/[A-Z]/g, (letter) => `_${letter.toLowerCase()}`);
+  for (const field of AWESOME_CLAUDE_CONTENT_SPEC.urlFields) {
+    if (!/[A-Z]/.test(field)) continue;
+    const snakeCase = toSnakeCase(field);
+    assert.equal(AWESOME_CLAUDE_CONTENT_SPEC.urlFields.has(snakeCase), true);
+    assert.equal(AWESOME_CLAUDE_CONTENT_SPEC.sourceUrlFields.includes(snakeCase), true);
+  }
+});
+
+test("documentation_url is present in both urlFields and sourceUrlFields (#9992)", () => {
+  assert.equal(AWESOME_CLAUDE_CONTENT_SPEC.urlFields.has("documentation_url"), true);
+  assert.equal(AWESOME_CLAUDE_CONTENT_SPEC.sourceUrlFields.includes("documentation_url"), true);
+});

test/unit/content-lane-duplicates.test.ts

@@ -214,6 +214,22 @@ describe("extractContentDuplicateSignals + strict match", () => {
     const m = findStrictContentDuplicateMatch(a, [b]);
     expect(m?.reasons.some((r) => r.includes("same normalized description"))).toBe(true);
   });
+
+  it("REGRESSION (#9992): an entry whose only URL frontmatter key is documentation_url still yields a non-empty urls signal", () => {
+    const sig = extractContentDuplicateSignals({
+      filePath: "content/skills/doc-only.mdx",
+      content: mdx({ title: "Doc Only", slug: "doc-only", documentation_url: "https://docs.acme.example/guide" }),
+    });
+    expect(sig.urls).toContain("https://docs.acme.example/guide");
+  });
+
+  it("does not pick up an unrelated non-URL frontmatter key into the urls signal", () => {
+    const sig = extractContentDuplicateSignals({
+      filePath: "content/skills/no-url.mdx",
+      content: mdx({ title: "No Url", slug: "no-url", pricing_model: "https://example.com/pricing-not-a-url-field" }),
+    });
+    expect(sig.urls).toEqual([]);
+  });
 });
 
 describe("normalizeUrl — RFC 3986 percent-encoding canonicalization for duplicate detection", () => {

test/unit/content-lane-source-evidence.test.ts

@@ -67,12 +67,24 @@ describe("extractSubmittedSourceUrls", () => {
     // was invisible to the source-evidence gate even though duplicates.ts (which reads urlFields) saw it.
     const pairs = extractSubmittedSourceUrls(mdx({ source_url: "https://github.com/acme/y" })).map((u) => `${u.field}:${u.url}`);
     expect(pairs).toContain("source_url:https://github.com/acme/y");
-    // Every snake_case alias urlFields carries is now recognized here too.
-    for (const field of ["docs_url", "download_url", "github_url", "package_url", "repo_url", "repository_url", "source_url", "website_url"]) {
-      expect(AWESOME_CLAUDE_CONTENT_SPEC.sourceUrlFields).toContain(field);
-      expect(AWESOME_CLAUDE_CONTENT_SPEC.urlFields.has(field)).toBe(true);
+  });
+
+  it("every camelCase urlFields member has its snake_case alias present in both urlFields and sourceUrlFields (mirrors #7250/#7445's pairing assertion; #9992)", () => {
+    // Derived, not hand-enumerated: a hard-coded list here (as before #9992) cannot catch the next URL field
+    // that gets added to urlFields without a matching snake_case alias — it would silently pass regardless.
+    const toSnakeCase = (field: string): string => field.replace(/[A-Z]/g, (letter) => `_${letter.toLowerCase()}`);
+    for (const field of AWESOME_CLAUDE_CONTENT_SPEC.urlFields) {
+      if (!/[A-Z]/.test(field)) continue;
+      const snakeCase = toSnakeCase(field);
+      expect(AWESOME_CLAUDE_CONTENT_SPEC.urlFields.has(snakeCase)).toBe(true);
+      expect(AWESOME_CLAUDE_CONTENT_SPEC.sourceUrlFields).toContain(snakeCase);
     }
   });
+
+  it("REGRESSION (#9992): extracts documentation_url the same way as documentationUrl", () => {
+    const urls = extractSubmittedSourceUrls(mdx({ documentation_url: "https://docs.acme.example/guide" }));
+    expect(urls).toEqual([{ field: "documentation_url", url: "https://docs.acme.example/guide" }]);
+  });
 });
 
 describe("checkSubmittedSourceEvidence", () => {