fix(home): stop silent rectification open after login (BUG-599)

Bare `/` was treating the latest history session as active, so a returning account could auto-open a failed rectification Case and left-align the starter home.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/app/globals.css

@@ -1903,11 +1903,13 @@ input:not([type="radio"]):not([type="checkbox"]):not([class^="ant-"]):not([class
 /* Starter workbench */
 .welcome {
   width: min(1040px, 100%);
+  margin-inline: auto;
   padding: var(--space-8) 0 var(--space-12);
 }
 
 .starter-list {
   width: min(1040px, 100%);
+  margin-inline: auto;
   display: grid;
   grid-template-columns: minmax(0, 1fr);
   gap: var(--space-6);
@@ -2229,6 +2231,7 @@ input:not([type="radio"]):not([type="checkbox"]):not([class^="ant-"]):not([class
 .composer-wrap-starter .composer,
 .composer-wrap-starter .composer-footer {
   width: min(1040px, 100%);
+  margin-inline: auto;
 }
 
 @media (min-width: 768px) and (max-width: 900px) {

frontend/src/app/page.tsx

@@ -231,7 +231,10 @@ import {
   bootstrapLoadingCopy,
   bootstrapPrepareSettled,
   bootstrapRevealDelayMs,
+  resolveStarterHomeLandingSessionId,
   sessionIdsToPrefetch,
+  shouldAutoOpenRectificationSession,
+  starterHomeLandingNeedsConsultation,
   type BootstrapPhase,
 } from "@/lib/home-bootstrap";
 
@@ -520,16 +523,19 @@ export default function Home() {
     return () => window.removeEventListener("popstate", onPopState);
   }, [hydrated]);
 
-  // A rectification session selected at bootstrap (deep link, refresh, the
-  // most recent session) is opened and hydrated during the prepare phase, so
-  // the reveal shows the surface itself rather than a plain transcript that is
-  // swapped out a moment later. After the reveal the same effect serves
-  // history navigation.
+  // A rectification session named in `?c=` (refresh, deep link, login return)
+  // is opened during prepare so the reveal shows the surface. Bare `/` after
+  // login must not open the latest history item in the background.
   useEffect(() => {
     if ((!hydrated && bootstrapPhase === "account")
       || !account
       || !modelCatalog
-      || activeSession?.sessionType !== "birth_time_rectification"
+      || !activeSession
+      || !shouldAutoOpenRectificationSession({
+        sessionType: activeSession.sessionType,
+        sessionId: activeSession.id,
+        search: window.location.search,
+      })
       || activeSession.id === rectificationSessionId
       || rectificationLoading
       || rectificationMutationPending
@@ -671,7 +677,11 @@ export default function Home() {
     dailyStarlanguageApplicable: Boolean(accountId) && profileComplete && natalMinuteAvailable,
     dailyStarlanguageSettled: dailyStarlanguage.kind !== "pending",
     entrySummarySettled: rectificationEntrySummarySettled,
-    rectificationApplicable: activeSession?.sessionType === "birth_time_rectification",
+    rectificationApplicable: shouldAutoOpenRectificationSession({
+      sessionType: activeSession?.sessionType,
+      sessionId: activeSession?.id,
+      search: typeof window === "undefined" ? "" : window.location.search,
+    }),
     rectificationSettled: activeSession?.id === rectificationSessionId
       || rectificationError !== ""
       || !profileComplete,
@@ -1013,7 +1023,35 @@ export default function Home() {
           search: window.location.search,
           storedReturnId: readLoginSessionReturn(),
         });
-        const activeListed = nextSessions.find((session) => session.id === bootstrapSelection.sessionId)
+        let landingSessionId = resolveStarterHomeLandingSessionId(
+          nextSessions,
+          bootstrapSelection.sessionId,
+          bootstrapSelection.urlAction,
+        );
+        if (starterHomeLandingNeedsConsultation(nextSessions, landingSessionId, bootstrapSelection.urlAction)) {
+          if (controller.signal.aborted) return;
+          const homeSession = createSession(
+            nextModelCatalog?.defaultModelId ?? "",
+            "consultation",
+            chartSnapshotForSession("self", [], nextProfile),
+          );
+          if (nextModelCatalog) {
+            await writeChatSession(homeSession.id, {
+              title: homeSession.title,
+              theme: homeSession.theme,
+              model_id: homeSession.modelId,
+              messages: [],
+              session_type: homeSession.sessionType,
+              rectification_case_id: homeSession.rectificationCaseId,
+              chart_profile_id: homeSession.chartProfileId,
+              chart_profile_name: homeSession.chartProfileName,
+              chart_profile_role: homeSession.chartProfileRole,
+            }, "create");
+          }
+          nextSessions = [homeSession, ...nextSessions];
+          landingSessionId = homeSession.id;
+        }
+        const activeListed = nextSessions.find((session) => session.id === landingSessionId)
           ?? nextSessions[0];
         if (activeListed && !activeListed.messagesHydrated && activeListed.sessionType === "consultation") {
           try {
@@ -1035,7 +1073,7 @@ export default function Home() {
         setStartGreeting(nextProfile.name.trim() ? createStartGreeting(nextProfile.name) : "");
         setOnboardingStep(missingProfileStep(nextProfile) ?? "name");
         setSessions(nextSessions);
-        setActiveSessionId(bootstrapSelection.sessionId);
+        setActiveSessionId(landingSessionId);
         if (bootstrapSelection.clearStoredReturn) clearLoginSessionReturn();
         if (bootstrapSelection.urlAction === "replace-clear") writeSessionUrl(null, "replace");
         if (bootstrapSelection.urlAction === "replace-selected") writeSessionUrl(bootstrapSelection.sessionId, "replace");
@@ -1744,7 +1782,7 @@ export default function Home() {
           </header>
 
         {!rectificationSurfaceOpen && (
-          <div ref={conversation} className={`conversation${!activeSession?.messages.length && Boolean(activeSession?.messagesHydrated) && !onboardingFormActive ? " is-empty" : ""}${!profileComplete ? " is-onboarding" : ""}${onboardingFormActive ? " is-onboarding-form" : ""}`}>
+          <div ref={conversation} className={`conversation${!onboardingFormActive && !activeSession?.messages.length && (Boolean(activeSession?.messagesHydrated) || activeSession?.sessionType !== "consultation") ? " is-empty" : ""}${!profileComplete ? " is-onboarding" : ""}${onboardingFormActive ? " is-onboarding-form" : ""}`}>
             {!activeSession?.messages.length ? (
             <div className="welcome">
               {!profileComplete ? (

frontend/src/lib/home-bootstrap.ts

@@ -8,8 +8,62 @@
  * settled, or when the prepare budget runs out — never with a spinner inside.
  */
 
+import { parseSessionUrlQuery } from "./chat-session-url.ts";
+
 export type BootstrapPhase = "account" | "prepare";
 
+export type LandingSession = Readonly<{
+  id: string;
+  sessionType: string;
+  messages: readonly unknown[];
+}>;
+
+export type LandingUrlAction = "keep" | "replace-selected" | "replace-clear" | "none";
+
+/**
+ * A rectification Case is opened only when the address bar names that session
+ * (`?c=`), including refresh and a login return that restored the URL. Bare `/`
+ * after login must not open the latest history item in the background.
+ */
+export function shouldAutoOpenRectificationSession(input: {
+  readonly sessionType: string | undefined;
+  readonly sessionId: string | undefined;
+  readonly search: string;
+}): boolean {
+  if (input.sessionType !== "birth_time_rectification" || !input.sessionId) return false;
+  return parseSessionUrlQuery(input.search).sessionId === input.sessionId;
+}
+
+/**
+ * Default `/` landing prefers an empty consultation so the starter home can
+ * center. Deep links and login-return URLs keep the requested session.
+ */
+export function resolveStarterHomeLandingSessionId(
+  sessions: readonly LandingSession[],
+  selectedId: string,
+  urlAction: LandingUrlAction,
+): string {
+  if (urlAction === "keep" || urlAction === "replace-selected") return selectedId;
+  const selected = sessions.find((session) => session.id === selectedId);
+  if (selected?.sessionType !== "birth_time_rectification") return selectedId;
+  const emptyConsultation = sessions.find(
+    (session) => session.sessionType === "consultation" && session.messages.length === 0,
+  );
+  if (emptyConsultation) return emptyConsultation.id;
+  const anyConsultation = sessions.find((session) => session.sessionType === "consultation");
+  return anyConsultation?.id ?? selectedId;
+}
+
+export function starterHomeLandingNeedsConsultation(
+  sessions: readonly LandingSession[],
+  landingId: string,
+  urlAction: LandingUrlAction,
+): boolean {
+  if (urlAction === "keep" || urlAction === "replace-selected") return false;
+  const landing = sessions.find((session) => session.id === landingId);
+  return !landing || landing.sessionType === "birth_time_rectification";
+}
+
 export const BOOTSTRAP_PREPARE_TIMEOUT_MS = 4000;
 export const SESSION_PREFETCH_COUNT = 5;
 
@@ -19,7 +73,7 @@ export type BootstrapPrepareState = Readonly<{
   dailyStarlanguageApplicable: boolean;
   dailyStarlanguageSettled: boolean;
   entrySummarySettled: boolean;
-  /** The selected session is a rectification session: its Case must be open and hydrated before the reveal. */
+  /** A URL-named rectification session must be opened and hydrated before reveal. */
   rectificationApplicable?: boolean;
   rectificationSettled?: boolean;
 }>;

frontend/tests/chat-session-url.test.ts

@@ -117,7 +117,7 @@ test("default bootstrap selection does not write a session URL", () => {
 
   const bootstrap = sourceBetween(page, "async function loadCloudData()", "void loadCloudData();");
   assert.match(bootstrap, /defaultSessionId: nextSessions\[0\]\.id/);
-  assert.match(bootstrap, /setActiveSessionId\(bootstrapSelection\.sessionId\)/);
+  assert.match(bootstrap, /setActiveSessionId\(landingSessionId\)/);
   assert.match(bootstrap, /urlAction === "replace-clear"/);
   assert.match(bootstrap, /urlAction === "replace-selected"/);
   assert.doesNotMatch(bootstrap, /writeSessionUrl\([^)]*, "push"\)/);

frontend/tests/home-bootstrap-reveal.test.ts

@@ -8,7 +8,10 @@ import {
   bootstrapLoadingCopy,
   bootstrapPrepareSettled,
   bootstrapRevealDelayMs,
+  resolveStarterHomeLandingSessionId,
   sessionIdsToPrefetch,
+  shouldAutoOpenRectificationSession,
+  starterHomeLandingNeedsConsultation,
 } from "../src/lib/home-bootstrap.ts";
 import { homeSurface } from "./home-surface.ts";
 
@@ -22,6 +25,65 @@ const starterHome = readFileSync(new URL("../src/components/starter-home.tsx", i
 const globalsCss = readFileSync(new URL("../src/app/globals.css", import.meta.url), "utf8");
 const staleClientRecovery = readFileSync(new URL("../src/components/stale-client-recovery.tsx", import.meta.url), "utf8");
 
+const rectificationId = "11111111-1111-4111-8111-111111111111";
+const consultationId = "22222222-2222-4222-8222-222222222222";
+const emptyConsultationId = "33333333-3333-4333-8333-333333333333";
+
+test("bare / after login does not auto-open the latest rectification session", () => {
+  assert.equal(shouldAutoOpenRectificationSession({
+    sessionType: "birth_time_rectification",
+    sessionId: rectificationId,
+    search: "",
+  }), false);
+  assert.equal(shouldAutoOpenRectificationSession({
+    sessionType: "birth_time_rectification",
+    sessionId: rectificationId,
+    search: `?c=${rectificationId}`,
+  }), true);
+  assert.equal(shouldAutoOpenRectificationSession({
+    sessionType: "birth_time_rectification",
+    sessionId: rectificationId,
+    search: `?c=${consultationId}`,
+  }), false);
+  assert.equal(shouldAutoOpenRectificationSession({
+    sessionType: "consultation",
+    sessionId: consultationId,
+    search: `?c=${consultationId}`,
+  }), false);
+});
+
+test("default landing replaces a latest rectification session with an empty consultation", () => {
+  const sessions = [
+    { id: rectificationId, sessionType: "birth_time_rectification", messages: [] },
+    { id: emptyConsultationId, sessionType: "consultation", messages: [] },
+    { id: consultationId, sessionType: "consultation", messages: [{ role: "user" }] },
+  ];
+  assert.equal(resolveStarterHomeLandingSessionId(sessions, rectificationId, "none"), emptyConsultationId);
+  assert.equal(resolveStarterHomeLandingSessionId(sessions, rectificationId, "replace-clear"), emptyConsultationId);
+  assert.equal(resolveStarterHomeLandingSessionId(sessions, rectificationId, "keep"), rectificationId);
+  assert.equal(resolveStarterHomeLandingSessionId(sessions, rectificationId, "replace-selected"), rectificationId);
+  assert.equal(resolveStarterHomeLandingSessionId(sessions, consultationId, "none"), consultationId);
+  assert.equal(
+    starterHomeLandingNeedsConsultation(
+      [{ id: rectificationId, sessionType: "birth_time_rectification", messages: [] }],
+      rectificationId,
+      "none",
+    ),
+    true,
+  );
+  assert.equal(
+    starterHomeLandingNeedsConsultation(sessions, emptyConsultationId, "none"),
+    false,
+  );
+  assert.equal(
+    starterHomeLandingNeedsConsultation(sessions, rectificationId, "keep"),
+    false,
+  );
+  assert.match(page, /resolveStarterHomeLandingSessionId\(/);
+  assert.match(page, /shouldAutoOpenRectificationSession\(/);
+  assert.match(page, /starterHomeLandingNeedsConsultation\(/);
+});
+
 test("prepare phase settles only when every applicable item has an answer", () => {
   const base = {
     profileComplete: true,

frontend/tests/rectification-surface-contract.test.ts

@@ -45,11 +45,13 @@ test("the rectification surface is revealed once: Case hydration precedes the sw
   assert.match(chat, /useEffect\(\(\) => \(\) => \{\s*runAbort\.current\?\.abort\(\);\s*snapshotAbort\.current\?\.abort\(\);\s*\}, \[\]\);/);
 });
 
-test("a rectification session selected at bootstrap is hydrated before the reveal, and popstate defers the same way", () => {
+test("a rectification session named in the URL is hydrated before the reveal; bare / does not", () => {
   // The resume effect runs during the prepare phase, not only after the reveal.
   assert.match(page, /if \(\(!hydrated && bootstrapPhase === "account"\)\s*\|\| !account/);
+  assert.match(page, /shouldAutoOpenRectificationSession\(\{/);
   assert.match(bootstrap, /if \(state\.rectificationApplicable && !state\.rectificationSettled\) return false;/);
-  assert.match(page, /rectificationApplicable: activeSession\?\.sessionType === "birth_time_rectification",\s*rectificationSettled: activeSession\?\.id === rectificationSessionId\s*\|\| rectificationError !== ""\s*\|\| !profileComplete,/);
+  assert.match(page, /rectificationApplicable: shouldAutoOpenRectificationSession\(\{/);
+  assert.match(page, /rectificationSettled: activeSession\?\.id === rectificationSessionId\s*\|\| rectificationError !== ""\s*\|\| !profileComplete,/);
   // One deadline constant for hydration and the home reveal.
   assert.match(read("../src/lib/rectification-surface-state.ts"), /export const RECTIFICATION_OPEN_HYDRATE_TIMEOUT_MS = BOOTSTRAP_PREPARE_TIMEOUT_MS;/);
   // History navigation goes through selectSession, which defers the switch (locked above).

frontend/tests/session-conversation-layout.test.ts

@@ -22,6 +22,16 @@ test("keeps onboarding transcript and intake card on the same session column", (
   assert.match(globalStyles, /\.conversation\.is-onboarding-form \.welcome \{[\s\S]*padding:\s*var\(--space-6\) var\(--session-column-gutter\) var\(--space-8\)/);
 });
 
+test("centers the starter home even when the conversation grid is not is-empty", () => {
+  const pageSource = readProjectFile("src/app/page.tsx");
+  assert.match(globalStyles, /\.welcome \{\s*width:\s*min\(1040px, 100%\);\s*margin-inline:\s*auto;/);
+  assert.match(globalStyles, /\.starter-list \{\s*width:\s*min\(1040px, 100%\);\s*margin-inline:\s*auto;/);
+  assert.match(
+    pageSource,
+    /!onboardingFormActive && !activeSession\?\.messages\.length && \(Boolean\(activeSession\?\.messagesHydrated\) \|\| activeSession\?\.sessionType !== "consultation"\) \? " is-empty"/,
+  );
+});
+
 test("keeps message motion restrained and honors reduced-motion preferences", () => {
   assert.match(messageRowSource, /gsap\.matchMedia\(\)/);
   assert.match(messageRowSource, /prefers-reduced-motion:\s*no-preference/);