fix(jobdanmark-search): back off on 429/5xx in detail instead of failing on the first attempt (#460)

`detail` called fetch() directly rather than going through the CLI's own
request wrappers, so it had none of the three things apiFetch/apiPost
guarantee: no 429/5xx retry loop, a hand-inlined User-Agent that would
drift from the exported USER_AGENT, and a timeout no wrapper test covered.
A rate-limited detail page wrote API_ERROR and exited after ONE attempt;
jobnet, jobbank, jobindex, linkedin, and freehire all retry up to six
times on the same response. /scrape calls detail once per shortlisted
posting, so a burst that tripped jobdanmark's limiter dropped those
postings (no description, no deadline) while any other portal rode it out.

Demonstrated by driving the real command handler with a stubbed 429 and
instant timers: 1 fetch attempt and exit 1 before, 7 after (initial try
plus six retries, the contract's schedule).

Add htmlFetch to helpers.ts with the same backoff, timeout, and shared
User-Agent as the JSON wrappers - 404 returns null so detail keeps its
NOT_FOUND contract - and route detail through it. The retry-backoff,
user-agent, and request-timeout suites now cover all three wrappers, and
the new detail-backoff.test.ts exercises the handler path itself; its two
retry cases fail against the bare fetch().

.agents/skills/jobdanmark-search/cli/src/commands/detail.ts

@@ -1,7 +1,7 @@
 import { defineCommand, option } from "@bunli/core"
 import { z } from "zod"
 import { parse } from "node-html-parser"
-import { BASE_URL, normalizeSlug, writeError } from "../helpers.js"
+import { BASE_URL, htmlFetch, normalizeSlug, writeError } from "../helpers.js"
 import { extractCity, toContractDate } from "./search.js"
 
 interface JsonLdJobPosting {
@@ -241,26 +241,15 @@ export const detail = defineCommand({
     const url = `${BASE_URL}/job/${slug}`
 
     try {
-      const response = await fetch(url, {
-        headers: {
-          "Accept": "text/html,application/xhtml+xml",
-          "User-Agent": "Mozilla/5.0 (compatible; jobdanmark-cli/1.0)",
-        },
-        signal: AbortSignal.timeout(15000),
-      })
+      // htmlFetch carries the portal contract's 429/5xx backoff, the request
+      // timeout, and the shared User-Agent; a bare fetch() here had none.
+      const html = await htmlFetch(url)
 
-      if (response.status === 404) {
+      if (html === null) {
         writeError("Job not found", "NOT_FOUND")
         process.exit(1)
       }
 
-      if (!response.ok) {
-        writeError(`API request failed: ${response.status} ${response.statusText}`, "API_ERROR")
-        process.exit(1)
-      }
-
-      const html = await response.text()
-
       if (signal.aborted) return
 
       const output = parseJobPostingFromHtml(html, slug, url)

.agents/skills/jobdanmark-search/cli/src/helpers.ts

@@ -64,6 +64,45 @@ export async function apiPost<T>(path: string, body: unknown): Promise<T> {
   throw new Error("API request failed after max retries")
 }
 
+/**
+ * Fetch a rendered jobdanmark.dk page as text, with the same 429/5xx backoff,
+ * request timeout, and User-Agent as apiFetch/apiPost. `detail` reads HTML
+ * rather than the JSON API; it used to call fetch() directly with none of the
+ * three, so a rate-limited detail page failed on the first 429 while every
+ * other portal's detail command retried. Returns null on 404 so the caller
+ * keeps its own NOT_FOUND contract.
+ */
+export async function htmlFetch(url: string): Promise<string | null> {
+  const maxRetries = 6
+  let delay = 500
+  for (let attempt = 0; attempt <= maxRetries; attempt++) {
+    const response = await fetch(url, {
+      headers: {
+        "Accept": "text/html,application/xhtml+xml",
+        "User-Agent": USER_AGENT,
+      },
+      signal: AbortSignal.timeout(15000),
+    })
+    if (response.status === 429 || response.status >= 500) {
+      if (attempt === maxRetries) {
+        throw new Error(`API request failed: ${response.status} ${response.statusText}`)
+      }
+      const jitter = Math.floor(Math.random() * 500)
+      await new Promise((resolve) => setTimeout(resolve, delay + jitter))
+      delay = Math.min(delay * 2, 5000)
+      continue
+    }
+    if (response.status === 404) {
+      return null
+    }
+    if (!response.ok) {
+      throw new Error(`API request failed: ${response.status} ${response.statusText}`)
+    }
+    return response.text()
+  }
+  throw new Error("API request failed after max retries")
+}
+
 export function writeError(error: string, code: string): void {
   process.stderr.write(JSON.stringify({ error, code }) + "\n")
 }

.agents/skills/jobdanmark-search/cli/tests/detail-backoff.test.ts

@@ -0,0 +1,134 @@
+import { afterEach, describe, expect, test } from "bun:test";
+import { detail } from "../src/commands/detail";
+
+// The portal contract requires backoff on 429/5xx, and `/scrape` calls
+// `detail` once per shortlisted posting - a burst that trips the rate limiter
+// is exactly when it matters. The handler used to call fetch() directly with
+// no retry loop: on a 429 it wrote API_ERROR and exited after ONE attempt,
+// while every other portal's detail command retried. These tests drive the
+// real command handler (not the wrapper in isolation) with a stubbed fetch,
+// instant timers, and process.exit turned into a throw so the exit path can
+// be asserted. On the pre-fix handler the first test sees 1 call and an exit.
+
+const originalFetch = globalThis.fetch;
+const originalSetTimeout = globalThis.setTimeout;
+const originalExit = process.exit;
+const originalLog = console.log;
+const originalStderrWrite = process.stderr.write;
+
+afterEach(() => {
+  globalThis.fetch = originalFetch;
+  globalThis.setTimeout = originalSetTimeout;
+  process.exit = originalExit;
+  console.log = originalLog;
+  process.stderr.write = originalStderrWrite;
+});
+
+const JSON_LD_PAGE = `<!doctype html><html><head>
+<script type="application/ld+json">{"@context":"https://schema.org","@type":"JobPosting",
+"title":"Data Engineer","datePosted":"2026-09-01","hiringOrganization":{"@type":"Organization","name":"Acme"},
+"description":"Build pipelines."}</script></head><body></body></html>`;
+
+function instantTimers() {
+  globalThis.setTimeout = ((fn: () => void) =>
+    originalSetTimeout(fn, 0)) as unknown as typeof setTimeout;
+}
+
+function stubFetch(responses: Array<() => Response>): { calls: number } {
+  const state = { calls: 0 };
+  globalThis.fetch = (async () => {
+    const i = Math.min(state.calls, responses.length - 1);
+    state.calls++;
+    return responses[i]();
+  }) as unknown as typeof fetch;
+  return state;
+}
+
+function captureOutput(): { stdout: string[]; stderr: string[] } {
+  const out = { stdout: [] as string[], stderr: [] as string[] };
+  console.log = ((...args: unknown[]) => out.stdout.push(args.join(" "))) as typeof console.log;
+  process.stderr.write = ((chunk: string | Uint8Array) => {
+    out.stderr.push(String(chunk));
+    return true;
+  }) as typeof process.stderr.write;
+  return out;
+}
+
+function firstStderrJson(out: { stderr: string[] }): unknown {
+  const firstLine = out.stderr.join("").trim().split("\n")[0];
+  return JSON.parse(firstLine);
+}
+
+class ExitCalled extends Error {
+  constructor(public code: number | undefined) {
+    super(`process.exit(${code})`);
+  }
+}
+
+function throwingExit() {
+  process.exit = ((code?: number) => {
+    throw new ExitCalled(code);
+  }) as unknown as typeof process.exit;
+}
+
+async function runDetail(slug: string): Promise<{ exit: number | null }> {
+  const handler = (detail as unknown as { handler: (ctx: unknown) => Promise<void> }).handler;
+  try {
+    await handler({ flags: { format: "json" }, positional: [slug], signal: new AbortController().signal });
+    return { exit: null };
+  } catch (err) {
+    if (err instanceof ExitCalled) return { exit: err.code ?? 0 };
+    throw err;
+  }
+}
+
+describe("detail backoff on the real handler path", () => {
+  test("retries a 429 and returns the posting on the next attempt", async () => {
+    instantTimers();
+    throwingExit();
+    const out = captureOutput();
+    const state = stubFetch([
+      () => new Response("", { status: 429, statusText: "Too Many Requests" }),
+      () => new Response(JSON_LD_PAGE, { status: 200 }),
+    ]);
+
+    const result = await runDetail("data-engineer-acme");
+
+    expect(result.exit).toBeNull();
+    expect(state.calls).toBe(2);
+    const parsed = JSON.parse(out.stdout.join("\n")) as { title: string; slug: string };
+    expect(parsed.title).toBe("Data Engineer");
+    expect(parsed.slug).toBe("data-engineer-acme");
+    expect(out.stderr.join("")).toBe("");
+  });
+
+  test("gives up after the initial attempt plus six retries and exits 1 with API_ERROR", async () => {
+    instantTimers();
+    throwingExit();
+    const out = captureOutput();
+    const state = stubFetch([() => new Response("", { status: 503, statusText: "Service Unavailable" })]);
+
+    const result = await runDetail("data-engineer-acme");
+
+    expect(result.exit).toBe(1);
+    expect(state.calls).toBe(7);
+    const err = firstStderrJson(out) as { code: string; error: string };
+    expect(err.code).toBe("API_ERROR");
+    expect(err.error).toMatch(/503/);
+  });
+
+  test("a 404 is not retried and still reports NOT_FOUND", async () => {
+    throwingExit();
+    const out = captureOutput();
+    const state = stubFetch([() => new Response("", { status: 404 })]);
+
+    const result = await runDetail("gone");
+
+    expect(result.exit).toBe(1);
+    expect(state.calls).toBe(1);
+    // The handler's own catch block sees the throwing process.exit stub and
+    // writes a second line - a test artifact, not CLI behaviour. The first
+    // stderr line is the contract.
+    expect(firstStderrJson(out)).toEqual({ error: "Job not found", code: "NOT_FOUND" });
+  });
+});

.agents/skills/jobdanmark-search/cli/tests/request-timeout.test.ts

@@ -1,5 +1,5 @@
 import { afterEach, describe, expect, test } from "bun:test";
-import { apiFetch, apiPost } from "../src/helpers";
+import { apiFetch, apiPost, htmlFetch } from "../src/helpers";
 
 // A stalled upstream connection (accepted socket, no response) would otherwise
 // hang the CLI forever - fetch has no default timeout. Assert both request
@@ -21,6 +21,17 @@ describe("request timeout", () => {
     expect(init?.signal).toBeInstanceOf(AbortSignal);
   });
 
+  test("htmlFetch passes an AbortSignal timeout to fetch", async () => {
+    let init: RequestInit | undefined;
+    globalThis.fetch = (async (_url: string | URL | Request, i?: RequestInit) => {
+      init = i;
+      return new Response("<html></html>", { status: 200 });
+    }) as unknown as typeof fetch;
+
+    await htmlFetch("https://jobdanmark.dk/job/x");
+    expect(init?.signal).toBeInstanceOf(AbortSignal);
+  });
+
   test("apiPost passes an AbortSignal timeout to fetch", async () => {
     let init: RequestInit | undefined;
     globalThis.fetch = (async (_url: string | URL | Request, i?: RequestInit) => {

.agents/skills/jobdanmark-search/cli/tests/retry-backoff.test.ts

@@ -1,11 +1,13 @@
 import { afterEach, describe, expect, test } from "bun:test";
-import { apiFetch, apiPost } from "../src/helpers";
+import { apiFetch, apiPost, htmlFetch } from "../src/helpers";
 
 // The portal contract requires backoff on 429/5xx. These tests pin the retry
 // loop offline: a stubbed fetch counts attempts, and a stubbed setTimeout
 // fires immediately so the exhaustion case does not sleep through the real
-// 500ms -> 5s backoff schedule. apiFetch and apiPost carry separate copies of
-// the loop, so both are exercised to keep them from drifting apart.
+// 500ms -> 5s backoff schedule. apiFetch, apiPost, and htmlFetch carry separate
+// copies of the loop, so all three are exercised to keep them from drifting
+// apart. htmlFetch is the one `detail` uses: before it existed, detail called
+// fetch() directly and a 429 failed on the first attempt (1 call, not 7).
 
 const originalFetch = globalThis.fetch;
 const originalSetTimeout = globalThis.setTimeout;
@@ -33,6 +35,7 @@ function stubFetch(responses: Array<() => Response>): { calls: number } {
 const wrappers: Array<[string, () => Promise<{ ok: boolean }>]> = [
   ["apiFetch", () => apiFetch<{ ok: boolean }>("/x")],
   ["apiPost", () => apiPost<{ ok: boolean }>("/x", {})],
+  ["htmlFetch", () => htmlFetch("https://jobdanmark.dk/job/x").then((html) => ({ ok: html !== null }))],
 ];
 
 for (const [name, call] of wrappers) {
@@ -65,3 +68,12 @@ for (const [name, call] of wrappers) {
     });
   });
 }
+
+describe("htmlFetch 404", () => {
+  test("returns null without retrying so detail keeps its NOT_FOUND contract", async () => {
+    const state = stubFetch([() => new Response("", { status: 404 })]);
+
+    expect(await htmlFetch("https://jobdanmark.dk/job/missing")).toBeNull();
+    expect(state.calls).toBe(1);
+  });
+});

.agents/skills/jobdanmark-search/cli/tests/user-agent.test.ts

@@ -1,5 +1,5 @@
 import { afterEach, describe, expect, test } from "bun:test";
-import { apiFetch, apiPost, USER_AGENT } from "../src/helpers";
+import { apiFetch, apiPost, htmlFetch, USER_AGENT } from "../src/helpers";
 
 // Bun's fetch injects an anonymous default User-Agent (Bun/1.3.10) when code
 // sets none. This CLI should say who is asking, in the honest style jobindex
@@ -46,3 +46,17 @@ describe("apiPost user agent", () => {
     expect(headerValue(init?.headers, "Content-Type")).toBe("application/json");
   });
 });
+
+describe("htmlFetch user agent", () => {
+  test("sends the shared User-Agent and asks for HTML", async () => {
+    let init: RequestInit | undefined;
+    globalThis.fetch = (async (_url: string | URL | Request, i?: RequestInit) => {
+      init = i;
+      return new Response("<html></html>", { status: 200 });
+    }) as unknown as typeof fetch;
+
+    await htmlFetch("https://jobdanmark.dk/job/x");
+    expect(headerValue(init?.headers, "User-Agent")).toBe(USER_AGENT);
+    expect(headerValue(init?.headers, "Accept")).toContain("text/html");
+  });
+});