W4.1+W4.2: anti-AI-tics house style + bureau nav (back/home everywhere)

Two complaints in one wave:

(W4.1) User: "Não pode ter vícios de IA como uso excessivo de '-' que a IA
coloca geralmente no lugar de vírgulas por exemplo. Isso deve fazer parte
do prompt geral."

  - New prompts/_house-style.md banning the 9 most common AI prose tells
    in both EN and PT-BR:
      1. Em dashes as comma replacements (—)
      2. Rule-of-three lists ("concrete, rigorous, and grounded")
      3. Conjunctive openers ("Moreover", "Notably", "Ademais")
      4. Superficial -ing analyses ("marking a shift", "destacando")
      5. Inflated symbolism + AI vocab (tapestry, navigate, delve,
         underscore, robust, multifaceted, marco histórico, ...)
      6. Negative parallelisms ("Not just X but Y")
      7. Vague attribution ("Some scholars say...")
      8. Summary closers ("In summary...", "Em suma...")
      9. Hedging fluff ("It's important to note...")
    Verbatim chunk quotes are explicitly exempt; preserve as-is.
  - claude.ts callClaude() lazily loads _house-style.md once per process
    and PREPENDS it to every detective's system prompt:
        composedSystem = houseStyle + "---" + detective.systemPrompt
    This means all 7 detectives + future ones get the rules without any
    per-prompt change.

(W4.2) User: "Quando entra em uma página da investigação não tem como
voltar! UX terrível!"

  - New <BureauNav> sticky topbar with explicit "← home" + "🔎 bureau"
    buttons + clickable breadcrumb trail. Always visible at the top of
    every bureau page so the user can escape in one click.
  - Wired into /bureau, /h/[hypothesisId], /c/[slug], /jobs/[id]. Each
    page passes its sensible parent crumb (/bureau#hypotheses,
    /bureau#reports, /bureau#jobs).
  - Replaces the previous plain-text "disclosure.top / hypothesis /
    H-0004" line which had no visual affordance.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

investigator-runtime/prompts/_house-style.md

@@ -0,0 +1,117 @@
+# House style — bureau voice (mandatory)
+
+This preamble is injected before every detective's system prompt. It applies
+to **all narrative prose you emit, in both EN and PT-BR**. Verbatim chunk
+quotes from the source corpus are exempt — preserve those as-is.
+
+Your output will be read by an editor who will reject anything that smells
+of AI-generated prose. The rules below are the editor's red pen.
+
+## 1. NO em dashes as comma replacements
+
+Forbidden: "...sobre o Novo México — território que abrigava os programas..."
+Forbidden: "He was the director — a man of severe temperament — who..."
+
+Use a comma. Or end the sentence and start a new one. If you genuinely need
+parentheses, use parentheses. Em dashes are allowed **only** for true range
+notation (e.g. `1948–1949`) and for verbatim quotes from the corpus that
+already contain them.
+
+In practice: if you can replace the dash with a comma without changing the
+meaning, you should have used the comma.
+
+## 2. NO rule-of-three lists
+
+Forbidden: "concrete, quantitative, and grounded"
+Forbidden: "rigorous, methodical, and exhaustive"
+Forbidden: "uma análise cuidadosa, metódica e exaustiva"
+
+Two adjectives is enough. Four is fine when you have four real items. The
+default three is filler — drop the weakest term.
+
+## 3. NO conjunctive fluff at sentence starts
+
+Forbidden openers: "Moreover", "Furthermore", "Notably", "Importantly",
+"It is worth noting", "It should be mentioned", "Crucially", "Indeed",
+"Ademais", "Além disso", "Vale destacar", "É importante notar",
+"Notadamente", "Cumpre observar".
+
+Start the sentence with the content. If the link is real, use plain "But",
+"And", "However", "So" — sparingly.
+
+## 4. NO superficial -ing analyses
+
+Forbidden: "marking a shift in policy", "highlighting the agency's concern",
+"reflecting a deeper anxiety", "underscoring the importance",
+"demonstrating the scale", "marcando uma mudança", "destacando a
+preocupação", "refletindo uma ansiedade", "sublinhando a importância".
+
+State the conclusion as a finite verb. "The agency changed its policy."
+Not "the document, marking a shift in policy, ...". The -ing tail is
+almost always filler that hedges the claim into mush.
+
+## 5. NO inflated symbolism / promotional adjectives
+
+Forbidden: "stands as a testament", "a beacon of", "speaks volumes",
+"watershed moment", "innovative", "groundbreaking", "remarkable",
+"unprecedented" (unless the corpus literally uses it), "robust",
+"comprehensive", "multifaceted", "nuanced", "rich tapestry", "complex
+landscape", "navigate the complexities", "leverage", "delve into",
+"shed light on", "paints a picture", "extensive", "myriad".
+
+PT-BR equivalents also forbidden: "marco histórico", "verdadeira riqueza",
+"complexa tapeçaria", "panorama complexo", "navegar pelas complexidades",
+"lança luz sobre", "demonstra de forma robusta", "abrangente",
+"multifacetado", "pinta um quadro".
+
+Show, don't characterize. If a result is remarkable, the reader will see
+that from the evidence — you don't need the adjective.
+
+## 6. NO negative parallelisms
+
+Forbidden: "Not just X, but Y." / "It's not X, it's Y."
+Forbidden: "Não apenas X, mas Y." / "Não se trata de X, mas de Y."
+
+Just say Y. The negation of X is rhetorical scaffolding the editor will
+delete.
+
+## 7. NO vague attribution
+
+Forbidden: "Some scholars argue...", "Many believe...", "It is widely
+held...", "Críticos argumentam...", "Muitos sustentam...".
+
+Cite the chunk: `[[doc-id/pNNN#cNNNN]]`. If no chunk supports the
+attribution, you don't get to make the claim.
+
+## 8. NO summary closers
+
+Forbidden last sentences: "In summary...", "In conclusion...",
+"Ultimately...", "Em suma...", "Em última análise...", "Em conclusão...",
+"Resumindo...".
+
+End on the last substantive sentence. The reader doesn't need to be told
+the section is ending.
+
+## 9. NO hedging fluff (separate from calibrated confidence_band)
+
+Forbidden: "It's important to note that...", "It bears mentioning...",
+"Of course...", "Naturally...", "Cabe ressaltar que...", "Naturalmente...",
+"É claro que...".
+
+The hedging you ARE allowed: posterior probability + Tetlock band, and
+explicit `[no evidence in corpus]` markers. Anything else hedge-shaped is
+filler.
+
+---
+
+## Quick self-check before emitting
+
+Read your draft and ask:
+- Did I use any em dash that could be a comma? Replace it.
+- Did I write any list of exactly three items? Drop the weakest one.
+- Did I start any sentence with "Moreover/Notably/Furthermore"? Cut it.
+- Did I use any word from the forbidden list? Find a plain alternative.
+- Did I write "in summary" / "em suma"? Delete that sentence.
+
+The bureau's voice is **plainspoken investigative**. Like a senior detective
+reporting facts to a colleague, not like a Wikipedia introduction.

investigator-runtime/src/lib/claude.ts

@@ -7,8 +7,28 @@
  * so the orchestrator can enforce the per-job budget cap.
  */
 import { spawn } from "node:child_process";
+import { readFile } from "node:fs/promises";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
 import { env } from "./env";
 
+const HERE = path.dirname(fileURLToPath(import.meta.url));
+const HOUSE_STYLE_PATH = path.resolve(HERE, "..", "..", "prompts", "_house-style.md");
+
+// Lazy-load the house style once per process. Detective system prompts get
+// this preamble prepended automatically (the bureau's anti-AI-tics rules:
+// no em dash as comma, no rule-of-three, no "Moreover", no inflated vocab).
+let _houseStyleCache: string | null | undefined;
+async function loadHouseStyle(): Promise<string | null> {
+  if (_houseStyleCache !== undefined) return _houseStyleCache;
+  try {
+    _houseStyleCache = await readFile(HOUSE_STYLE_PATH, "utf-8");
+  } catch {
+    _houseStyleCache = null;
+  }
+  return _houseStyleCache;
+}
+
 export interface ClaudeCallArgs {
   /** Free-form prompt body to send. */
   prompt: string;
@@ -69,8 +89,15 @@ export async function callClaude(args: ClaudeCallArgs): Promise<ClaudeCallResult
   // long multi-line content reliably (the CLI complained "Input must be
   // provided either through stdin or as a prompt argument when using --print"
   // for prompts past a few KB). Stdin is unambiguous.
-  const fullPrompt = args.systemPrompt
-    ? `${args.systemPrompt}\n\n---\n\n${args.prompt}`
+  // Compose system prompt: house style (anti-AI-tics) + detective persona.
+  // House style goes FIRST so the model treats it as a hard constraint that
+  // wraps the detective's discipline.
+  const houseStyle = await loadHouseStyle();
+  const composedSystem = [houseStyle, args.systemPrompt]
+    .filter((s): s is string => typeof s === "string" && s.trim().length > 0)
+    .join("\n\n---\n\n");
+  const fullPrompt = composedSystem
+    ? `${composedSystem}\n\n---\n\n${args.prompt}`
     : args.prompt;
 
   const t0 = Date.now();

web/app/bureau/page.tsx

@@ -8,6 +8,7 @@
 import Link from "next/link";
 import { pgQuery } from "@/lib/retrieval/db";
 import { AuthBar } from "@/components/auth-bar";
+import { BureauNav } from "@/components/bureau-nav";
 
 export const runtime = "nodejs";
 export const dynamic = "force-dynamic";
@@ -141,13 +142,9 @@ export default async function BureauPage() {
 
   return (
     <div className="min-h-screen bg-[#0a0e1a] text-[#e7ecf3]">
+      <BureauNav crumbs={[{ label: "bureau" }]} />
       <AuthBar />
-      <div className="mx-auto max-w-6xl px-4 py-8 pt-16">
-        <div className="text-[11px] text-[#5a6678] font-mono mb-2">
-          <Link href="/" className="hover:text-[#7fdbff]">disclosure.top</Link>
-          <span className="mx-1">/</span>
-          <span className="text-[#e0c080]">bureau</span>
-        </div>
+      <div className="mx-auto max-w-6xl px-4 py-6 pt-4">
 
         <header className="mb-8 border-b border-[rgba(224,192,128,0.32)] pb-4">
           <h1 className="font-mono text-3xl text-[#e0c080]">▍ The Investigation Bureau</h1>

web/app/c/[slug]/page.tsx

@@ -11,6 +11,7 @@ import { readFile } from "node:fs/promises";
 import path from "node:path";
 import { MarkdownBody } from "@/components/markdown-body";
 import { AuthBar } from "@/components/auth-bar";
+import { BureauNav } from "@/components/bureau-nav";
 
 export const runtime = "nodejs";
 export const dynamic = "force-dynamic";
@@ -74,15 +75,13 @@ export default async function CaseReportPage({
 
   return (
     <div className="min-h-screen bg-[#0a0e1a] text-[#e7ecf3]">
+      <BureauNav crumbs={[
+        { label: "bureau", href: "/bureau" },
+        { label: "reports", href: "/bureau#reports" },
+        { label: slug },
+      ]} />
       <AuthBar />
-      <div className="mx-auto max-w-3xl px-4 py-8 pt-16">
-        <div className="text-[11px] text-[#5a6678] font-mono mb-2">
-          <Link href="/" className="hover:text-[#7fdbff]">disclosure.top</Link>
-          <span className="mx-1">/</span>
-          <span>case-report</span>
-          <span className="mx-1">/</span>
-          <span className="text-[#e0c080]">{slug}</span>
-        </div>
+      <div className="mx-auto max-w-3xl px-4 py-6 pt-4">
 
         <div className="rounded-lg border border-[rgba(224,192,128,0.18)] bg-gradient-to-br from-[rgba(224,192,128,0.06)] to-transparent p-4 mb-6">
           <div className="text-[10px] font-mono text-[#5a6678] uppercase mb-2">

web/app/h/[hypothesisId]/page.tsx

@@ -17,6 +17,7 @@ import { readFile } from "node:fs/promises";
 import path from "node:path";
 import { pgQuery } from "@/lib/retrieval/db";
 import { AuthBar } from "@/components/auth-bar";
+import { BureauNav } from "@/components/bureau-nav";
 import { RedTeamRequestButton } from "@/components/red-team-request-button";
 
 export const runtime = "nodejs";
@@ -196,15 +197,13 @@ export default async function HypothesisPage({
 
   return (
     <div className="min-h-screen bg-[#0a0e1a] text-[#e7ecf3]">
+      <BureauNav crumbs={[
+        { label: "bureau", href: "/bureau" },
+        { label: "hypotheses", href: "/bureau#hypotheses" },
+        { label: hypothesisId },
+      ]} />
       <AuthBar />
-      <div className="mx-auto max-w-5xl px-4 py-8 pt-16">
-        <div className="text-[11px] text-[#5a6678] font-mono mb-2">
-          <Link href="/" className="hover:text-[#7fdbff]">disclosure.top</Link>
-          <span className="mx-1">/</span>
-          <span>hypothesis</span>
-          <span className="mx-1">/</span>
-          <span className="text-[#7fdbff]">{hypothesisId}</span>
-        </div>
+      <div className="mx-auto max-w-5xl px-4 py-6 pt-4">
 
         {/* Header */}
         <div className="rounded-lg border border-[rgba(127,219,255,0.18)] bg-gradient-to-br from-[rgba(127,219,255,0.08)] to-transparent p-5">

web/app/jobs/[id]/page.tsx

@@ -18,6 +18,7 @@ import { notFound } from "next/navigation";
 import Link from "next/link";
 import { pgQuery } from "@/lib/retrieval/db";
 import { AuthBar } from "@/components/auth-bar";
+import { BureauNav } from "@/components/bureau-nav";
 import { JobStatusPoller } from "@/components/job-status-poller";
 
 export const runtime = "nodejs";
@@ -109,15 +110,13 @@ export default async function JobPage({
 
   return (
     <div className="min-h-screen bg-[#0a0e1a] text-[#e7ecf3]">
+      <BureauNav crumbs={[
+        { label: "bureau", href: "/bureau" },
+        { label: "jobs", href: "/bureau#jobs" },
+        { label: job.job_id.slice(0, 8) },
+      ]} />
       <AuthBar />
-      <div className="mx-auto max-w-5xl px-4 py-8 pt-16">
-        <div className="text-[11px] text-[#5a6678] font-mono mb-2">
-          <Link href="/" className="hover:text-[#7fdbff]">disclosure.top</Link>
-          <span className="mx-1">/</span>
-          <span>investigation</span>
-          <span className="mx-1">/</span>
-          <span className="text-[#7fdbff]">{job.job_id.slice(0, 8)}</span>
-        </div>
+      <div className="mx-auto max-w-5xl px-4 py-6 pt-4">
 
         <div className={`rounded-lg border border-[rgba(127,219,255,0.18)] bg-gradient-to-br ${detectiveBg} to-transparent p-5`}>
           <div className="flex items-baseline justify-between gap-4 flex-wrap">

web/components/bureau-nav.tsx

@@ -0,0 +1,62 @@
+/**
+ * BureauNav — top navigation bar present on every bureau page.
+ *
+ * Solves "I'm stuck on this page, there's no way back" UX. Shows:
+ *   - "← Home" (always → /)
+ *   - "🔎 Bureau" (always → /bureau)
+ *   - Breadcrumb trail of current page (passed via props)
+ *
+ * Server component. No client-side history needed because the parent links
+ * are deterministic (every bureau page has a known parent in the hierarchy).
+ */
+import Link from "next/link";
+import { ArrowLeft, Home } from "lucide-react";
+
+export interface Crumb {
+  /** Display label. */
+  label: string;
+  /** When omitted the crumb is rendered as the current page (no link). */
+  href?: string;
+}
+
+export function BureauNav({ crumbs }: { crumbs: Crumb[] }) {
+  return (
+    <nav className="sticky top-0 z-30 bg-[#0a0e1a]/95 backdrop-blur border-b border-[rgba(224,192,128,0.18)]">
+      <div className="mx-auto max-w-6xl px-4 py-2 flex items-center gap-3 flex-wrap text-[12px] font-mono">
+        <Link
+          href="/"
+          className="inline-flex items-center gap-1 px-2 py-1 rounded border border-[rgba(127,219,255,0.30)] text-[#7fdbff] hover:bg-[rgba(127,219,255,0.08)]"
+          aria-label="Voltar para a home"
+        >
+          <ArrowLeft size={12} />
+          <Home size={12} />
+          <span>home</span>
+        </Link>
+
+        <Link
+          href="/bureau"
+          className="inline-flex items-center gap-1 px-2 py-1 rounded border border-[#e0c080] text-[#e0c080] hover:bg-[rgba(224,192,128,0.08)]"
+          aria-label="Hub do bureau"
+        >
+          🔎 <span>bureau</span>
+        </Link>
+
+        {crumbs.length > 0 && (
+          <div className="text-[11px] text-[#5a6678] flex items-center gap-1.5 flex-wrap">
+            <span className="mx-1">/</span>
+            {crumbs.map((c, i) => (
+              <span key={`${c.label}-${i}`} className="inline-flex items-center gap-1.5">
+                {c.href ? (
+                  <Link href={c.href} className="hover:text-[#7fdbff]">{c.label}</Link>
+                ) : (
+                  <span className="text-[#e7ecf3]">{c.label}</span>
+                )}
+                {i < crumbs.length - 1 && <span>/</span>}
+              </span>
+            ))}
+          </div>
+        )}
+      </div>
+    </nav>
+  );
+}