diff --git a/marketing-site/data/sample-chapter.js b/marketing-site/data/sample-chapter.js
index 1833e1d..e92102c 100644
--- a/marketing-site/data/sample-chapter.js
+++ b/marketing-site/data/sample-chapter.js
@@ -56,6 +56,7 @@ const RE04 = {
   time: "~15 min",
   cost: "≈ $0.03",
   vertical: "Real Estate",
+  shortTitle: "Market brief",
   title: "Draft a property-market brief with an AI agent without leaking client data.",
   problem:
     "You need a neighborhood market brief for a client meeting this week. The listing sheet and client notes cannot go into a public model.",
@@ -115,6 +116,7 @@ const RE05 = {
   time: "~12 min",
   cost: "≈ $0.02",
   vertical: "Real Estate",
+  shortTitle: "Listing copy",
   title: "Rewrite a listing description from public comps without pasting the client address book.",
   problem:
     "You need listing copy that sounds like this house, not every house on the street. The CRM holds owner notes and the showing list. Those do not go into a public model.",
@@ -188,6 +190,7 @@ export const CHAPTER = {
     { id: "RE-05", href: "#re-05", title: "Listing copy" },
   ],
   stakes: {
+    id: "stakes",
     heading: "The stakes",
     paragraphs: [
       "A listing that stalls because the market brief is late is a lost weekend. A listing that leaks because you pasted the client sheet into a public model is a lost license. Real estate work runs on both clocks: the showing at 4pm, and the file that must never leave the office.",
@@ -195,6 +198,7 @@ export const CHAPTER = {
     ],
   },
   constraints: {
+    id: "constraints",
     heading: "Constraints you cannot ignore",
     paragraphs: [
       "You already work in MLS exports, a CRM, and a phone that rings during the write-up. Done is a brief the client can read in a meeting, with numbers you can stand behind, reviewed by a human. Public models are useful for draft and classify. They are not a filing cabinet.",
@@ -202,12 +206,14 @@ export const CHAPTER = {
     ],
   },
   practice: {
+    id: "practice",
     heading: "How we work here",
     paragraphs: [
       "Redact locally. Prompt with a sample or a stripped file. Review against a checklist. Share the artifact, not the workflow text. The first job this week is the neighborhood market brief. Run it on sample comps before you touch a live listing.",
     ],
   },
   between: {
+    id: "between",
     heading: "The brief is half the meeting",
     paragraphs: [
       "The brief gets you into the room with numbers. The other half is the listing copy: public comps, a description that does not sound like every other house on the street, and an address book that never belongs in the prompt. Same rule. Different job.",
@@ -224,3 +230,33 @@ export const CHAPTER = {
     "Local redaction fields: owner_name, phone, exact_address.",
   ],
 };
+
+/** Outline groups for the chapter map. Headings come from the essay objects. */
+export function buildOutline(chapter, recipes) {
+  return [
+    {
+      label: "Essay",
+      items: [chapter.stakes, chapter.constraints, chapter.practice, chapter.between].map((s) => ({
+        id: s.id,
+        label: s.heading,
+      })),
+    },
+    {
+      label: "Workflows",
+      items: recipes.map((r) => ({
+        id: r.anchor,
+        recipeId: r.id,
+        label: r.id + " · " + r.shortTitle,
+        time: r.time,
+        shortTitle: r.shortTitle,
+      })),
+    },
+    {
+      label: "End",
+      items: [
+        { id: "further", label: "Further workflows" },
+        { id: "sources", label: "Sources" },
+      ],
+    },
+  ];
+}