diff --git a/app/api/tutor.py b/app/api/tutor.py
index b4dd8dd..21f16ce 100644
--- a/app/api/tutor.py
+++ b/app/api/tutor.py
@@ -105,12 +105,37 @@ def editor_context(
     LMS-page widget. Owner-checked; generic fallback on any miss so
     the widget always mounts and never leaks another learner's title.
     """
-    fallback = TutorEditorContext(
-        assignment_title="Lab workspace", session_id=f"editor-{port}"
-    )
     store = _store(request)
+
+    def _fallback() -> TutorEditorContext:
+        # NEVER key on the ephemeral code-server port: it changes on
+        # every container restart, so an `editor-<port>` session_id
+        # silently fragments/orphans the learner's tutor history. Fall
+        # back to the learner's own enrollment (the SAME stable
+        # `lms-<enrollment.id>` the LMS-page widget uses — shared
+        # history); only if they have no enrollment, a stable per-user
+        # key. Both survive editor restarts.
+        try:
+            if store is not None:
+                enrs = store.list_learner_enrollments(
+                    learner_id=str(user.id), limit=50
+                )
+                if enrs:  # store returns most-recently-updated first
+                    e = enrs[0]
+                    return TutorEditorContext(
+                        assignment_title=getattr(e, "course_title", None)
+                        or "Lab workspace",
+                        session_id=f"lms-{e.id}",
+                    )
+        except Exception:
+            pass
+        return TutorEditorContext(
+            assignment_title="Lab workspace",
+            session_id=f"editor-user-{user.id}",
+        )
+
     if store is None:
-        return fallback
+        return _fallback()
     try:
         sessions = [
             s
@@ -121,13 +146,13 @@ def editor_context(
         sessions.sort(key=lambda s: (s.status.value == "running", s.updated_at), reverse=True)
         session = sessions[0] if sessions else None
         if session is None:
-            return fallback
+            return _fallback()
         enrollment = store.get_learner_enrollment(session.enrollment_id)
         if enrollment is None or enrollment.learner_id != str(user.id):
-            return fallback
+            return _fallback()
         return TutorEditorContext(
             assignment_title=enrollment.course_title or "Lab workspace",
             session_id=f"lms-{enrollment.id}",
         )
     except Exception:
-        return fallback
+        return _fallback()
diff --git a/app/main.py b/app/main.py
index 4c1ff9a..d4abc2b 100644
--- a/app/main.py
+++ b/app/main.py
@@ -69,6 +69,8 @@ def _configure_logging() -> Path:
 
 
 _LOG_PATH = _configure_logging()
+from urllib.parse import quote
+
 from fastapi.responses import HTMLResponse, RedirectResponse
 from fastapi.staticfiles import StaticFiles
 from fastapi.templating import Jinja2Templates
@@ -303,12 +305,28 @@ def _user_state(user) -> dict | None:
     }
 
 
+def _login_redirect(request: Request) -> RedirectResponse:
+    """Send an unauthenticated user to /login but PRESERVE where they
+    were going (login.html honours ?next), so a deep link like
+    /?enrollment=<id> returns them there after sign-in instead of
+    dumping them on /courses. Target is server-derived (path+query) so
+    it is inherently same-site; non-relative values fall back."""
+    target = request.url.path
+    if request.url.query:
+        target += "?" + request.url.query
+    if not target.startswith("/") or target.startswith("//"):
+        target = "/courses"
+    return RedirectResponse(
+        url="/login?next=" + quote(target, safe=""), status_code=302
+    )
+
+
 @app.get("/", tags=["system"], include_in_schema=False)
 def root(request: Request):
     user = current_user_optional(request)
     # Logged-out experience is just the login form.
     if user is None:
-        return RedirectResponse(url="/login", status_code=302)
+        return _login_redirect(request)
     # The bare "/" hero is deprecated — /courses is the canonical
     # landing. Only "/?enrollment=<id>" still renders here: that is the
     # pinned learner workspace/brief/review experience (where enrolling
@@ -328,7 +346,7 @@ def root(request: Request):
 def courses(request: Request):
     user = current_user_optional(request)
     if user is None:
-        return RedirectResponse(url="/login", status_code=302)
+        return _login_redirect(request)
     svc = _ensure_lms_service(request.app)
     lms_state = build_lms_state(
         catalog=svc.list_catalog(),
diff --git a/app/services/tutor_service.py b/app/services/tutor_service.py
index 2e55246..04d0263 100644
--- a/app/services/tutor_service.py
+++ b/app/services/tutor_service.py
@@ -96,9 +96,20 @@
 _SKIP_SUFFIXES = {".lock", ".pyc", ".pyo", ".so", ".o", ".a", ".class", ".jar"}
 _BINARY_SUFFIXES = {".png", ".jpg", ".jpeg", ".gif", ".webp", ".pdf", ".zip", ".tar", ".gz", ".bin"}
 
-# Hard size limits to keep prompt cost bounded.
-_PER_FILE_MAX_BYTES = 8 * 1024   # skip a file if it exceeds this on its own
-_TOTAL_CODE_MAX_BYTES = 40 * 1024  # truncate code-snapshot collection at this aggregate
+# Hard size limits to keep prompt cost bounded. NOTE: over-limit files
+# are TRUNCATED, never skipped — a learner's implemented app.py is
+# routinely >8KB and dropping it entirely is why the tutor used to say
+# "I can't see your app.py, paste it".
+_PER_FILE_MAX_BYTES = 24 * 1024
+_TOTAL_CODE_MAX_BYTES = 64 * 1024
+
+# Source files the learner actually edits — these win the snapshot
+# budget over README/sample-data/config so the tutor always sees code.
+_CODE_SUFFIXES = {
+    ".py", ".js", ".ts", ".tsx", ".jsx", ".go", ".java", ".rb", ".rs",
+    ".c", ".cc", ".cpp", ".h", ".hpp", ".cs", ".php", ".kt", ".swift",
+    ".scala", ".sql", ".sh", ".rs", ".ex", ".exs",
+}
 
 # Failure detail caps.
 _FAILURE_MAX_BYTES = 4 * 1024
@@ -125,12 +136,19 @@ def _load_env_file(path: str | None) -> None:
 
 
 def _read_text_safely(path: Path, max_bytes: int) -> str | None:
+    """Read up to ``max_bytes`` of text. Over-limit files are
+    TRUNCATED (with a marker), never dropped — the learner's main code
+    file is frequently large and silently skipping it blinds the tutor.
+    Returns None only for non-files / OS errors."""
     try:
         if not path.is_file():
             return None
-        if path.stat().st_size > max_bytes:
-            return None
-        return path.read_text(encoding="utf-8", errors="replace")
+        with path.open("rb") as fh:
+            raw = fh.read(max_bytes + 1)
+        text = raw[:max_bytes].decode("utf-8", errors="replace")
+        if len(raw) > max_bytes:
+            text += "\n... [truncated]\n"
+        return text
     except OSError as exc:
         logger.debug("[tutor] could not read %s: %s", path, exc)
         return None
@@ -158,8 +176,34 @@ def _build_code_snapshot(root: Path) -> str:
     if not files:
         return ""
 
-    # Sort by modification time (newest first) so the learner's recent edits win the budget.
-    files.sort(key=lambda pair: pair[1].stat().st_mtime, reverse=True)
+    # Learner source code first (so it wins the budget over README /
+    # sample data / config, whose mtimes get bumped by platform
+    # re-publishes), then most-recently-modified within each group.
+    def _rank(pair):
+        rel, abs_path = pair
+        is_code = abs_path.suffix.lower() in _CODE_SUFFIXES
+        try:
+            mtime = abs_path.stat().st_mtime
+        except OSError:
+            mtime = 0.0
+        return (0 if is_code else 1, -mtime)
+
+    files.sort(key=_rank)
+
+    # TODO(tutor-context): the set of "the file(s) the learner edits"
+    # is hardcoded to app.py for now. Generalise this — derive it from
+    # the deliverable's editable/visible files (the course spec already
+    # knows `learner_brief.files_to_edit` / `visible_files`) so any
+    # course's primary file(s) get the same guaranteed inclusion.
+    # Until then: pin app.py (prefer public/starter/app.py) to the very
+    # front so it is ALWAYS included regardless of ranking/budget.
+    _APP_PY = "public/starter/app.py"
+    files.sort(
+        key=lambda pair: (
+            0 if str(pair[0]) == _APP_PY else
+            1 if pair[1].name == "app.py" else 2
+        )
+    )
 
     tree_lines = [str(rel) for rel, _ in files[:80]]
     body_lines: list[str] = []
@@ -183,8 +227,22 @@ def _build_code_snapshot(root: Path) -> str:
     return "File tree:\n" + "\n".join(f"  {ln}" for ln in tree_lines) + "\n\nFile contents:\n" + "".join(body_lines)
 
 
+# Learner workspaces live at <repo>/learner_workspaces/<learner_id>/
+# <shared_workflow_run_id>/workspace (mirrors lms_service._workspace_root).
+# tutor_service is app/services/, so parents[2] == repo root.
+_LEARNER_WS_BASE = Path(__file__).resolve().parents[2] / "learner_workspaces"
+
+
 def _read_brief_files(root: Path) -> tuple[str, str]:
-    """Return (project_brief, deliverables) as strings."""
+    """Return (project_brief, deliverables) as strings.
+
+    Workspaces now seed a single consolidated ``README.md`` (the brief
+    + a Deliverables section); ``project_brief.md`` / ``deliverables.md``
+    are legacy and no longer written. Prefer README; fall back to the
+    legacy split files for older workspaces."""
+    readme = _read_text_safely(root / "README.md", 48 * 1024) or ""
+    if readme.strip():
+        return readme.strip(), ""
     brief = _read_text_safely(root / "project_brief.md", 32 * 1024) or ""
     delivs = _read_text_safely(root / "deliverables.md", 32 * 1024) or ""
     return brief.strip(), delivs.strip()
@@ -303,30 +361,63 @@ def _resolve_session_context(self, session_id: str) -> tuple[str, str, str, str
         if enrollment_id is None and session is not None:
             enrollment_id = getattr(session, "enrollment_id", None)
 
+        # Resolve the enrollment once — used both to locate the live
+        # learner workspace and for the snapshot-brief fallback.
+        enr = None
+        if enrollment_id:
+            try:
+                enr = self._store.get_learner_enrollment(enrollment_id)
+            except Exception as exc:
+                logger.debug("[tutor] enrollment lookup failed for %s: %s", session_id, exc)
+                enr = None
+
+        # Find the learner's live workspace dir so the tutor can READ
+        # their code (the #1 thing it needs to actually help). Prefer the
+        # session's workspace_root; it is frequently unset on editor
+        # sessions, so fall back to the deterministic LMS path
+        # learner_workspaces/<learner_id>/<shared_workflow_run_id>/workspace.
         brief, delivs, code = "", "", ""
+        ws_dir: Path | None = None
         if session is not None:
-            workspace_root = Path(getattr(session, "workspace_root", "") or "")
-            if str(workspace_root) and workspace_root.exists():
-                brief, delivs = _read_brief_files(workspace_root)
-                code = _build_code_snapshot(workspace_root)
+            sroot = Path(getattr(session, "workspace_root", "") or "")
+            if str(sroot) and sroot.exists():
+                ws_dir = sroot
+        if ws_dir is None and enr is not None:
+            cand = (
+                _LEARNER_WS_BASE
+                / str(enr.learner_id)
+                / str(enr.shared_workflow_run_id)
+                / "workspace"
+            )
+            if cand.exists():
+                ws_dir = cand
+        if ws_dir is not None:
+            brief, delivs = _read_brief_files(ws_dir)
+            code = _build_code_snapshot(ws_dir)
 
         # No materialized workspace yet (learner hasn't opened the editor)
         # — use the publish snapshot's brief so the tutor still has the
         # full spec. The tutor must NEVER ask the learner to paste it.
-        if not brief and enrollment_id:
+        if not brief and enr is not None:
             try:
-                enr = self._store.get_learner_enrollment(enrollment_id)
-                if enr is not None:
-                    snap = self._store.get_publish_snapshot(enr.publish_snapshot_id)
-                    if snap is not None:
+                snap = self._store.get_publish_snapshot(enr.publish_snapshot_id)
+                if snap is not None:
                         from app.services.learner_package_runtime import (
                             deliverables_markdown,
                             project_brief_markdown,
                         )
-                        brief = project_brief_markdown(snap) or brief
+                        # Only accept real, non-empty strings — a
+                        # malformed snapshot (or a test double) must not
+                        # let a non-str flow into _build_system_prompt's
+                        # "".join (TypeError).
+                        _b = project_brief_markdown(snap)
+                        if isinstance(_b, str) and _b.strip():
+                            brief = _b
                         lp = getattr(snap, "learner_package", None)
                         if lp is not None and getattr(lp, "deliverables", None):
-                            delivs = deliverables_markdown(lp.deliverables) or delivs
+                            _d = deliverables_markdown(lp.deliverables)
+                            if isinstance(_d, str) and _d.strip():
+                                delivs = _d
             except Exception as exc:
                 logger.debug("[tutor] snapshot brief fallback failed for %s: %s", session_id, exc)
 
diff --git a/app/static/lab-tutor.css b/app/static/lab-tutor.css
index 8ad8e34..f869eaf 100644
--- a/app/static/lab-tutor.css
+++ b/app/static/lab-tutor.css
@@ -430,14 +430,18 @@
   background: #fff;
   border-radius: 10px;
   padding: 20px;
-  max-width: 94vw;
-  max-height: 82vh;
+  width: 92vw;
+  max-width: 92vw;
+  max-height: 84vh;
   overflow: auto;
 }
+/* Force the diagram to scale UP to fill the lightbox. Mermaid emits an
+   inline max-width/width on the <svg> that otherwise pins it at its
+   small in-panel size, so "Click to enlarge" appeared to do nothing. */
 .lt-mermaid-modal-inner svg {
-  width: auto;
-  height: auto;
-  max-width: 88vw;
+  width: 100% !important;
+  max-width: none !important;
+  height: auto !important;
   display: block;
 }
 .lt-mermaid pre {
diff --git a/app/static/lab-tutor.js b/app/static/lab-tutor.js
index 8ef3733..079b3e3 100644
--- a/app/static/lab-tutor.js
+++ b/app/static/lab-tutor.js
@@ -99,14 +99,37 @@
   // Click-to-enlarge: a 5-10 node diagram is unreadable in the narrow
   // chat panel, so let the learner open any rendered diagram in a big
   // zoomable overlay (and copy its source). Basic, no deps.
-  function openMermaidLightbox(svgHtml, source) {
+  async function openMermaidLightbox(_svgHtml, source) {
     const prev = document.querySelector(".lt-mermaid-modal");
     if (prev) prev.remove();
     const modal = document.createElement("div");
     modal.className = "lt-mermaid-modal";
     const inner = document.createElement("div");
     inner.className = "lt-mermaid-modal-inner";
-    inner.innerHTML = svgHtml;
+    inner.textContent = "Enlarging diagram…";
+    // RE-RENDER from source with a fresh id. Re-injecting the panel's
+    // SVG string duplicates Mermaid's id-scoped <style>/marker defs, so
+    // the clone renders unstyled/collapsed (an empty white box). A
+    // clean re-render with a unique id sizes correctly to the lightbox.
+    (async () => {
+      const mermaid = await loadMermaid();
+      try {
+        if (!mermaid) throw new Error("mermaid unavailable");
+        const { svg } = await mermaid.render(
+          "lt-mermaid-zoom-" + (++mermaidIdCounter), source
+        );
+        inner.innerHTML = svg;
+      } catch (e) {
+        inner.innerHTML = "";
+        const note = document.createElement("div");
+        note.className = "lt-mermaid-error";
+        note.textContent = "Couldn't render diagram. Source:";
+        const pre = document.createElement("pre");
+        pre.textContent = source;
+        inner.appendChild(note);
+        inner.appendChild(pre);
+      }
+    })();
     const bar = document.createElement("div");
     bar.className = "lt-mermaid-modal-bar";
     const copyBtn = document.createElement("button");
@@ -279,8 +302,9 @@
     const expandBtn = document.createElement("button");
     expandBtn.className = "lt-icon-btn lt-expand";
     expandBtn.type = "button";
-    expandBtn.setAttribute("aria-label", "Maximise Lab Tutor");
-    expandBtn.appendChild(expandIcon());
+    // Default to the large/maximised panel; the button reduces it.
+    expandBtn.setAttribute("aria-label", "Minimise Lab Tutor");
+    expandBtn.appendChild(collapseIcon());
 
     const closeBtn = document.createElement("button");
     closeBtn.className = "lt-icon-btn lt-close";
@@ -296,7 +320,10 @@
     header.appendChild(headerTitle);
     header.appendChild(headerActions);
 
-    let expanded = false;
+    // Large by default — diagrams + long replies need the room; the
+    // header button (collapseIcon, set above) reduces it back to compact.
+    let expanded = true;
+    panel.classList.add("lt-panel--expanded");
     function toggleExpanded(force) {
       const next = typeof force === "boolean" ? force : !expanded;
       if (next === expanded) return;
diff --git a/app/static/lms.css b/app/static/lms.css
index 5cb99e7..73eebdd 100644
--- a/app/static/lms.css
+++ b/app/static/lms.css
@@ -512,6 +512,14 @@
 }
 
 .info-pill strong {
+  /* Reset the bleed from `.submission-item strong` (the date-heading
+     rule: display:block; font-size:14px; margin-bottom:6px) — equal
+     specificity but later in the file, so it otherwise wins and the
+     value renders block-level, larger, and offset from its label. */
+  display: inline;
+  margin: 0;
+  font-size: inherit;
+  line-height: inherit;
   color: var(--text);
   font-weight: 600;
 }
@@ -647,6 +655,7 @@
 .submission-item-meta {
   display: flex;
   flex-wrap: wrap;
+  align-items: center;
   gap: 8px;
 }
 
@@ -948,7 +957,7 @@
 
 .review-guidance-summary {
   margin: 10px 0 0;
-  color: var(--ink);
+  color: var(--text);
   line-height: 1.55;
 }
 
@@ -971,7 +980,7 @@
 .review-guidance-section ul,
 .review-guidance-section ol {
   margin: 0;
-  color: var(--ink);
+  color: var(--text);
   font-size: 13px;
   line-height: 1.55;
 }
@@ -1083,7 +1092,7 @@
 
 .test-result-name {
   font-weight: 600;
-  color: var(--ink);
+  color: var(--text);
   font-size: 13px;
   word-break: break-word;
 }
@@ -1136,7 +1145,7 @@
 
 .test-result-headline {
   margin: 6px 0 0;
-  color: var(--ink);
+  color: var(--text);
   font-size: 13px;
   line-height: 1.5;
 }
@@ -1145,7 +1154,7 @@
   list-style: disc;
   margin: 0;
   padding: 12px 16px 14px 36px;
-  color: var(--ink);
+  color: var(--text);
   font-size: 13px;
   line-height: 1.55;
   border-top: 1px solid var(--line);
@@ -1186,7 +1195,7 @@
   font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
   font-size: 12px;
   line-height: 1.5;
-  color: var(--ink);
+  color: var(--text);
   white-space: pre-wrap;
   word-break: break-word;
   background: transparent;
@@ -1207,7 +1216,7 @@
 .test-result-example .we-hint-text {
   font-size: 13px;
   line-height: 1.55;
-  color: var(--ink);
+  color: var(--text);
 }
 
 .writeup-shell {
diff --git a/app/static/lms.js b/app/static/lms.js
index 86c2d94..6d8cbbc 100644
--- a/app/static/lms.js
+++ b/app/static/lms.js
@@ -49,9 +49,13 @@
     return String(t ?? "").replace(/^\s*Production(?:-Quality)?\s+/i, "").trim();
   }
 
-  // 15+/18 (>=15 marks) is treated as "solved"/green in the UI. The
-  // backend status stays authoritative for data; this is render-only.
-  const GOOD_ACCURACY_MARKS = 15;
+  // ONE learner-facing pass rule for EVERY surface (submit banner,
+  // submission-history pill, latest-review card, deliverable chips) so
+  // the same submission can never read "Failed" in one place and
+  // "Solved" in another. The bar is the documented one ("≥ 22 / 25" in
+  // the brief = 88%). backendStatus === "passed" stays an override for
+  // any flow that already records a hard pass.
+  const PASS_RATE_BAR = 0.88;
 
   // Concept-level hint per failing rubric — bridges the gap between
   // "what's wrong" (the worked example) and the IR/technique a learner
@@ -139,8 +143,10 @@
   }
 
   function isSolved(passed, total, backendStatus) {
-    const p = Number(passed || 0);
-    return backendStatus === "passed" || p >= GOOD_ACCURACY_MARKS || (total && p === Number(total));
+    if (backendStatus === "passed") return true;
+    const t = Number(total || 0);
+    if (!t) return false;
+    return Number(passed || 0) / t >= PASS_RATE_BAR;
   }
 
   function titleCase(value) {
@@ -1338,9 +1344,9 @@
           ${historyByAttempt.map((submission) => `
             <div class="submission-item">
               <strong>${escapeHtml(formatDate(submission.created_at))}</strong>
-              <p>${escapeHtml(titleCase(submission.status))} · ${escapeHtml(`${submission.passed_tests}/${submission.total_tests} checks passed`)}</p>
+              <p>${escapeHtml(`${isSolved(submission.passed_tests, submission.total_tests, submission.status) ? "Solved" : "Needs work"} · ${submission.passed_tests}/${submission.total_tests} checks passed`)}</p>
               <div class="submission-item-meta">
-                ${renderStatusPill(submission.status === "passed" ? "passed" : "blocked", titleCase(submission.status))}
+                ${renderStatusPill(isSolved(submission.passed_tests, submission.total_tests, submission.status) ? "passed" : "blocked", isSolved(submission.passed_tests, submission.total_tests, submission.status) ? "Solved" : "Needs work")}
                 ${renderInfoPill("Pass rate", percent(submission.pass_rate))}
                 ${renderInfoPill("Submitted", formatDate(submission.created_at))}
               </div>
@@ -1614,9 +1620,12 @@
       const latestSubmission = gradedExperience.latest_assignment_submission;
       stopSubmitProgress();
 
+      const latestSolved = latestSubmission
+        ? isSolved(latestSubmission.passed_tests, latestSubmission.total_tests, latestSubmission.status)
+        : false;
       uiState.submissionFeedback = {
-        kind: latestSubmission?.status === "passed" ? "success" : "error",
-        title: latestSubmission?.status === "passed" ? "Project reviewed" : "Project needs another pass",
+        kind: latestSolved ? "success" : "error",
+        title: latestSolved ? "Project reviewed" : "Project needs another pass",
         message: latestSubmission
           ? `${latestSubmission.passed_tests}/${latestSubmission.total_tests} checks passed.`
           : "Grading finished.",
@@ -1627,7 +1636,7 @@
 
       if (latestSubmission) {
         showToast(
-          latestSubmission.status === "passed" ? "success" : "info",
+          latestSolved ? "success" : "info",
           "Review finished",
           `${latestSubmission.passed_tests}/${latestSubmission.total_tests} checks passed.`
         );
diff --git a/app/templates/dashboard.html b/app/templates/dashboard.html
index 659f7b6..fda5d99 100644
--- a/app/templates/dashboard.html
+++ b/app/templates/dashboard.html
@@ -4,6 +4,7 @@
     <meta charset="utf-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1" />
     <title>Create Course Draft</title>
+    <link rel="icon" href="https://www.scaler.com/favicon.ico" />
     <link rel="stylesheet" href="/static/app-shell.css?v=__DASHBOARD_ASSET_VERSION__" />
     <link rel="stylesheet" href="/static/dashboard.css?v=__DASHBOARD_ASSET_VERSION__" />
   </head>
diff --git a/app/templates/docs.html b/app/templates/docs.html
index 4b734ff..8183b2b 100644
--- a/app/templates/docs.html
+++ b/app/templates/docs.html
@@ -4,6 +4,7 @@
     <meta charset="utf-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1" />
     <title>API Docs</title>
+    <link rel="icon" href="https://www.scaler.com/favicon.ico" />
     <link rel="stylesheet" href="/static/app-shell.css" />
     <link rel="stylesheet" href="/static/docs.css" />
     <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/swagger-ui-dist@5/swagger-ui.css" />
diff --git a/app/templates/draft_timeline.html b/app/templates/draft_timeline.html
index 5b644c2..70e8442 100644
--- a/app/templates/draft_timeline.html
+++ b/app/templates/draft_timeline.html
@@ -4,6 +4,7 @@
     <meta charset="utf-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1" />
     <title>Draft Timeline</title>
+    <link rel="icon" href="https://www.scaler.com/favicon.ico" />
     <link rel="stylesheet" href="/static/app-shell.css?v=__DRAFT_TIMELINE_ASSET_VERSION__" />
     <link rel="stylesheet" href="/static/draft-timeline.css?v=__DRAFT_TIMELINE_ASSET_VERSION__" />
   </head>
diff --git a/app/templates/login.html b/app/templates/login.html
index 51a25bc..eedb5f3 100644
--- a/app/templates/login.html
+++ b/app/templates/login.html
@@ -135,7 +135,10 @@ <h1>Sign in to continue</h1>
   });
   if (resp.ok) {
     const params = new URLSearchParams(location.search);
-    location.href = params.get("next") || "/courses";
+    const next = params.get("next") || "";
+    // Only same-site relative paths ("/x", not "//evil" or "https://").
+    const safe = /^\/(?!\/)/.test(next) ? next : "/courses";
+    location.href = safe;
   } else {
     document.getElementById("err").textContent = "Invalid email or password.";
   }
diff --git a/docs/DEPLOYMENT_RUNBOOK.md b/docs/DEPLOYMENT_RUNBOOK.md
index f82d820..e08ea07 100644
--- a/docs/DEPLOYMENT_RUNBOOK.md
+++ b/docs/DEPLOYMENT_RUNBOOK.md
@@ -131,3 +131,159 @@ for the exact, idempotent procedure (backs up the snapshot payload first).
 `pip install -r requirements.txt` pulls the CPU PyTorch wheel and **zero**
 `nvidia-*`/CUDA packages. `faiss-cpu` and `rank_bm25` are CPU-only by
 design. Keep that index line if you edit the file.
+
+---
+
+## HTTPS migration (HTTP → TLS via nginx + certbot)
+
+**Status: EXECUTED 2026-05-18 — live at https://labs.scaler.com.**
+What was actually done (differs slightly from the original plan, kept
+for the renewal/rollback record):
+- `dnf install -y certbot python3-certbot-nginx` (was not installed).
+- Cert issued with the **nginx authenticator, certonly** (no
+  installer/rewrite): `certbot certonly --nginx -d labs.scaler.com
+  --agree-tos --register-unsafely-without-email -n`. Auto-renew timer
+  installed by certbot; renewal re-uses the nginx authenticator (no
+  webroot needed). **No ops email** — add one later via `certbot
+  update_account` if expiry mail is wanted.
+- nginx conf **hand-written** (not via `--nginx` installer, which
+  mangles the regex `/editor/` locations + `sub_filter`): a `listen 80
+  … return 301 https://$host$request_uri;` redirect server + a `listen
+  443 ssl default_server` server that reuses the editor regex
+  locations / `sub_filter` / WS-upgrade / `X-Forwarded-Proto $scheme`
+  **verbatim**. Backups: `/etc/nginx/conf.d/course-gen-codex.conf
+  .pre-tls.bak.<ts>`; the staged source is in the repo at
+  `infra/nginx/labs.scaler.com.conf` (committed) — rollback = restore
+  the `.bak`, `nginx -t && systemctl reload nginx`.
+- Env cutover in `/opt/course-gen-codex/.env` (backed up to
+  `.env.pre-tls.bak.<ts>`): `SESSION_COOKIE_SECURE=true`,
+  `COURSE_GEN_EDITOR_PUBLIC_BASE=https://labs.scaler.com`; then
+  `systemctl restart course-gen-codex.service`.
+- Verified end-to-end over https: 301 redirect; `Secure` session
+  cookie; catalog/enroll/seed; in-editor tutor `editor-context`
+  returns the stable `lms-<enrollment.id>` (not `editor-<port>`);
+  tutor chat persisted + rehydrated; a full baseline submission
+  round-trip (grader Docker pipeline) returned a scorecard.
+
+Original plan/notes below retained for renewals & rollback.
+
+**Decision: domain + nginx + Let's Encrypt (`certbot`).** A trusted
+cert **cannot** be issued for the bare IP `18.236.242.248` — a domain
+is mandatory.
+
+### Prerequisites (gather before touching the host)
+
+- `labs.scaler.com` — the hostname that will serve the app (e.g.
+  `labs.example.com`). Fill in everywhere below.
+- DNS: an **A record** `labs.scaler.com → 18.236.242.248`, propagated
+  (`dig +short labs.scaler.com` returns the IP) BEFORE running certbot
+  (HTTP-01 challenge hits `labs.scaler.com:80`).
+- EC2 **security group**: inbound **443/tcp** open (and keep 80/tcp
+  open — certbot HTTP-01 + the 80→443 redirect need it). AWS
+  console/CLI op, separate from the app deploy.
+- Host has `nginx`; install certbot: `sudo dnf install -y certbot
+  python3-certbot-nginx` (AL2023) or distro equivalent.
+
+### App-side changes (no code — env only; flip AT cutover)
+
+Both live in the service env (systemd unit / `.env` consumed by
+`course-gen-codex.service`). They must change **together with** TLS
+going live, never before:
+
+- `SESSION_COOKIE_SECURE=true` — auth cookies then carry `Secure`
+  (`samesite=lax` already). If set true while still on http, the
+  cookie is never sent → total lockout. Honored by
+  `app/api/auth_routes.py` `_set_session_cookie`.
+- `COURSE_GEN_EDITOR_PUBLIC_BASE=https://labs.scaler.com` — in-editor URLs
+  (`learner_studio_service.py`) become https; avoids mixed-content /
+  insecure code-server links.
+
+No source changes: grep confirmed no hardcoded `http://18.236...` in
+`app/` templates/JS; both couplings are env-driven.
+
+### HTTPS-safety audit (code, verified $0 — 2026-05-18)
+
+- **Tutor: HTTPS-safe, no change.** Both the page widget and the
+  in-editor widget use a **relative** base. `lab-tutor-editor-boot.js`
+  mounts with `baseUrl:""`; `lab-tutor.js` fetches `cfg.baseUrl +
+  "/v1/tutor/*"` with `credentials:"same-origin"`. On
+  `https://labs.scaler.com` (app) and `https://labs.scaler.com/editor/
+  <port>/` (code-server) the origin is identical → calls stay
+  same-origin https, the `Secure`+`lax` cookie is sent, no mixed
+  content. `LAB_TUTOR_BASE_URL` is **irrelevant** to the browser widget
+  (not used by the boot path) — no env needed for the tutor.
+- **Tutor history: preserved.** Server-authoritative (Postgres, M34)
+  keyed by `(user_id, session_id)`; `session_id = lms-<enrollment.id>`
+  (origin/scheme-independent). The widget rehydrates via the relative
+  `GET /v1/tutor/history` on open. The old origin's localStorage cache
+  isn't visible at the new domain (origin-scoped) but is transparently
+  rebuilt from the server — **no history loss** (exactly the failure
+  mode M34 prevents).
+- **Editor (code-server): no app change.** The existing
+  `conf.d/course-gen-codex.conf` editor location already sets
+  `Upgrade $http_upgrade` / `Connection upgrade` and
+  `X-Forwarded-Proto $scheme` — over the 443 server `$scheme`=https, so
+  code-server auto-serves over `wss`. The ONLY risk is nginx-config
+  mechanics (below), not code.
+
+### Procedure (run on unfreeze, in this order)
+
+1. Confirm DNS: `dig +short labs.scaler.com` → `18.236.242.248`.
+2. Open :443 in the EC2 SG; confirm 80 still open.
+3. **Use `certbot certonly`, NOT `certbot --nginx`.** The live
+   `conf.d/course-gen-codex.conf` has **regex `location ~
+   ^/editor/(?<eport>…)`** blocks, WS upgrade headers, and a
+   `sub_filter` that injects `lab-tutor-editor-boot.js` — `--nginx`
+   auto-rewrite is known to mangle regex locations / drop `sub_filter`.
+   Instead:
+   - `sudo certbot certonly --webroot -w /usr/share/nginx/html
+     -d labs.scaler.com -m <ops-email> --agree-tos -n`
+     (or `--standalone` on :80 briefly if no webroot).
+   - **Hand-edit `conf.d/course-gen-codex.conf`**: add `listen 443
+     ssl;` + `ssl_certificate /etc/letsencrypt/live/labs.scaler.com/
+     fullchain.pem;` + `ssl_certificate_key …/privkey.pem;` +
+     `server_name labs.scaler.com;` to the **existing** server block
+     (which already has the app + editor + sub_filter + WS directives —
+     reuse it verbatim, just add TLS). Add a second tiny server:
+     `listen 80; server_name labs.scaler.com; return 301
+     https://$host$request_uri;`.
+   - `sudo nginx -t && sudo systemctl reload nginx`.
+   - Confirm auto-renew: `systemctl status certbot-renew.timer`
+     (`certonly` still installs the renewal timer; renewal needs no
+     nginx rewrite since we edited by hand).
+4. Verify BOTH app and editor over TLS:
+   - `curl -sI https://labs.scaler.com/login` → 200
+   - `curl -sI https://labs.scaler.com/static/lms.js` → 200
+   - open a live `/editor/<port>/` over https → code-server loads, its
+     **websocket connects** (DevTools → Network → WS shows `101`), and
+     the lab-tutor bubble appears (the `sub_filter` injection survived).
+5. Flip the two env vars (`SESSION_COOKIE_SECURE=true`,
+   `COURSE_GEN_EDITOR_PUBLIC_BASE=https://labs.scaler.com`) →
+   `sudo systemctl restart course-gen-codex.service`.
+6. Smoke (standard block, https): login, static assets, `/v1/tutor/*`
+   401 unauth, a full register→enroll→editor round-trip; verify the
+   session cookie shows `Secure`; **open the in-editor tutor, send a
+   message, reopen — history rehydrates**; no mixed-content console
+   errors.
+
+### Rollback
+
+- App: revert the two env vars → restart (instant; back to working
+  http behavior).
+- Edge: **before hand-editing, `sudo cp conf.d/course-gen-codex.conf
+  conf.d/course-gen-codex.conf.pre-tls.bak`** (there are already
+  `.bak.<ts>` siblings — follow that convention). Rollback = restore
+  the `.bak`, `sudo nginx -t && sudo systemctl reload nginx`. Cert
+  files are inert if unreferenced. (We use `certbot certonly` + a
+  hand-edit, so there's no `certbot rollback` of nginx — the `.bak` is
+  the rollback.)
+- DNS/SG changes are independently reversible.
+
+### Notes
+
+- One cert covers app + editor (same host, nginx path-proxy) — no
+  per-editor-port cert needed.
+- Renewal is automatic (certbot timer); no app redeploy on renew.
+- After cutover, update the smoke-test base in this runbook and any
+  `COURSE_GEN_EDITOR_PUBLIC_BASE` references from
+  `http://18.236.242.248` to `https://labs.scaler.com`.
diff --git a/docs/superpowers/course-gen-backlog.md b/docs/superpowers/course-gen-backlog.md
index 5a47e12..7777657 100644
--- a/docs/superpowers/course-gen-backlog.md
+++ b/docs/superpowers/course-gen-backlog.md
@@ -852,6 +852,34 @@ nothing but the internal `workspace_seeded.txt` marker.
 
 ---
 
+## 27. In-editor tutor history fragments under the ephemeral `editor-<port>` session
+
+**Status:** Backlog. Generic — affects every lab with the lab tutor.
+
+**Originating direct fix:** Customer Support Bot. Audited tutor history
+across IP↔CNAME (2026-05-18). The DB is fine: history is keyed
+`(user_id, session_id)` with `session_id = lms-<enrollment.id>`
+(origin/scheme-independent), so IP vs `labs.scaler.com` does **not**
+lose data — the apparent break is just host-scoped auth cookie +
+origin-scoped localStorage on the transition (re-login on the new host
+restores it). But the live data showed one `editor-35517` session:
+`tutor.py` `editor-context` falls back to
+`TutorEditorContext(session_id=f"editor-{port}")` when it can't map the
+code-server port to an enrollment. Code-server ports are **ephemeral**
+(reassigned per container/restart), so any history persisted under
+`editor-<port>` is orphaned on the next editor restart — the in-editor
+tutor "forgets" independent of any domain change.
+
+**Generalization:** the in-editor widget must always resolve to the
+stable `lms-<enrollment.id>` session. Options: make `editor-context`
+fail closed (no tutor / clear "not linked" state) instead of minting a
+volatile `editor-<port>` session; or have the port→enrollment mapping
+be authoritative and never persist/serve chat under `editor-<port>`.
+Where: `app/api/tutor.py` (`editor-context`), `tutor_service` history
+key, `lab-tutor-editor-boot.js`.
+
+---
+
 ## How to add to this list
 
 When making a direct course fix:
diff --git a/infra/nginx/labs.scaler.com.conf b/infra/nginx/labs.scaler.com.conf
new file mode 100644
index 0000000..24956f5
--- /dev/null
+++ b/infra/nginx/labs.scaler.com.conf
@@ -0,0 +1,53 @@
+server {
+    listen 80 default_server;
+    listen [::]:80 default_server;
+    server_name _;
+    return 301 https://$host$request_uri;
+}
+
+server {
+    listen 443 ssl default_server;
+    listen [::]:443 ssl default_server;
+    server_name labs.scaler.com;
+
+    ssl_certificate     /etc/letsencrypt/live/labs.scaler.com/fullchain.pem;
+    ssl_certificate_key /etc/letsencrypt/live/labs.scaler.com/privkey.pem;
+    ssl_protocols TLSv1.2 TLSv1.3;
+    ssl_prefer_server_ciphers off;
+
+    client_max_body_size 10M;
+
+    proxy_read_timeout 300s;
+    proxy_send_timeout 300s;
+    proxy_connect_timeout 75s;
+
+    location ~ ^/editor/(?<eport>[0-9]+)/(?<rest>.*)$ {
+        proxy_pass http://127.0.0.1:$eport/$rest$is_args$args;
+        proxy_set_header Accept-Encoding "";
+        sub_filter_once on;
+        sub_filter '</head>' '<script src="/static/lab-tutor-editor-boot.js" data-editor-port="$eport"></script></head>';
+        proxy_http_version 1.1;
+        proxy_set_header Upgrade $http_upgrade;
+        proxy_set_header Connection $connection_upgrade;
+        proxy_set_header Host $host;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+        proxy_read_timeout 3600s;
+        proxy_send_timeout 3600s;
+    }
+
+    location ~ ^/editor/(?<eport>[0-9]+)$ {
+        return 302 /editor/$eport/;
+    }
+
+    location / {
+        proxy_pass http://127.0.0.1:8040;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+        proxy_http_version 1.1;
+        proxy_set_header Upgrade $http_upgrade;
+        proxy_set_header Connection $connection_upgrade;
+    }
+}
diff --git a/scripts/support_bot_course/build_bundle.py b/scripts/support_bot_course/build_bundle.py
index c74322b..e7849a4 100644
--- a/scripts/support_bot_course/build_bundle.py
+++ b/scripts/support_bot_course/build_bundle.py
@@ -354,11 +354,15 @@ def scenario_yaml(c: dict) -> str:
             r'  pattern: "(?s).+"',
         ]
     # Citation grading: recall (>=0.5 of gold cited) AND precision (every
-    # cited id must be a GOLD id). Only on `answer` cases with a gold
-    # citation — never on a non-answer (subset_match fails on empty
-    # target; a non-answer never cites). Gold is the semantically
-    # supporting article, so a lexical-only ranker fails the VM cases.
-    if (c["skill"] == "S1" or c["skill"] == "S6") and g["citations"]:
+    # cited id must be a GOLD id). Applied to EVERY grounded-`answer`
+    # scenario that has a gold citation — not just S1/S6. Without this,
+    # a no-op returning {"action":"answer"} with no citations vacuously
+    # passes S2/S4/S5/S7 answer scenarios (schema+action+abstained all
+    # match the constant), so the grader fails to discriminate. Never on
+    # a non-answer (citations==[] there; subset_match fails on empty
+    # target). Gold is the semantically supporting article, so a
+    # lexical-only ranker still fails the vocabulary-mismatch cases.
+    if g["action"] == "answer" and g["citations"]:
         lines += [
             "- kind: oracle_set_overlap",
             f"  target: {sid}.body.citations",
diff --git a/scripts/support_bot_course/scenarios/09_policy_answer_smallrefund.yaml b/scripts/support_bot_course/scenarios/09_policy_answer_smallrefund.yaml
index 2c50b0b..664dc0e 100644
--- a/scripts/support_bot_course/scenarios/09_policy_answer_smallrefund.yaml
+++ b/scripts/support_bot_course/scenarios/09_policy_answer_smallrefund.yaml
@@ -23,3 +23,11 @@ rubrics:
 - kind: literal_match
   target: call_policy_answer_smallrefund.body.abstained
   expected: false
+- kind: oracle_set_overlap
+  target: call_policy_answer_smallrefund.body.citations
+  gold_set_path: setup_data.gold.policy_answer_smallrefund.citations
+  min_recall: 0.5
+- kind: subset_match
+  target: call_policy_answer_smallrefund.body.citations
+  acceptable_source: setup_data.gold.policy_answer_smallrefund.citations
+  min_overlap: 1.0
diff --git a/scripts/support_bot_course/scenarios/14_pii_contact.yaml b/scripts/support_bot_course/scenarios/14_pii_contact.yaml
index c2312a9..4881296 100644
--- a/scripts/support_bot_course/scenarios/14_pii_contact.yaml
+++ b/scripts/support_bot_course/scenarios/14_pii_contact.yaml
@@ -23,6 +23,14 @@ rubrics:
 - kind: literal_match
   target: call_pii_contact.body.abstained
   expected: false
+- kind: oracle_set_overlap
+  target: call_pii_contact.body.citations
+  gold_set_path: setup_data.gold.pii_contact.citations
+  min_recall: 0.5
+- kind: subset_match
+  target: call_pii_contact.body.citations
+  acceptable_source: setup_data.gold.pii_contact.citations
+  min_overlap: 1.0
 - kind: numeric_range
   target: call_pii_contact.body.redactions
   min_value: 2
diff --git a/scripts/support_bot_course/scenarios/15_pii_card.yaml b/scripts/support_bot_course/scenarios/15_pii_card.yaml
index fc43c29..d512f5d 100644
--- a/scripts/support_bot_course/scenarios/15_pii_card.yaml
+++ b/scripts/support_bot_course/scenarios/15_pii_card.yaml
@@ -23,6 +23,14 @@ rubrics:
 - kind: literal_match
   target: call_pii_card.body.abstained
   expected: false
+- kind: oracle_set_overlap
+  target: call_pii_card.body.citations
+  gold_set_path: setup_data.gold.pii_card.citations
+  min_recall: 0.5
+- kind: subset_match
+  target: call_pii_card.body.citations
+  acceptable_source: setup_data.gold.pii_card.citations
+  min_overlap: 1.0
 - kind: numeric_range
   target: call_pii_card.body.redactions
   min_value: 1
diff --git a/scripts/support_bot_course/scenarios/16_pii_ssn.yaml b/scripts/support_bot_course/scenarios/16_pii_ssn.yaml
index d210b40..12150d2 100644
--- a/scripts/support_bot_course/scenarios/16_pii_ssn.yaml
+++ b/scripts/support_bot_course/scenarios/16_pii_ssn.yaml
@@ -23,6 +23,14 @@ rubrics:
 - kind: literal_match
   target: call_pii_ssn.body.abstained
   expected: false
+- kind: oracle_set_overlap
+  target: call_pii_ssn.body.citations
+  gold_set_path: setup_data.gold.pii_ssn.citations
+  min_recall: 0.5
+- kind: subset_match
+  target: call_pii_ssn.body.citations
+  acceptable_source: setup_data.gold.pii_ssn.citations
+  min_overlap: 1.0
 - kind: numeric_range
   target: call_pii_ssn.body.redactions
   min_value: 2
diff --git a/scripts/support_bot_course/scenarios/18_inj_legitq_override.yaml b/scripts/support_bot_course/scenarios/18_inj_legitq_override.yaml
index f02c774..0171a28 100644
--- a/scripts/support_bot_course/scenarios/18_inj_legitq_override.yaml
+++ b/scripts/support_bot_course/scenarios/18_inj_legitq_override.yaml
@@ -23,3 +23,11 @@ rubrics:
 - kind: literal_match
   target: call_inj_legitq_override.body.abstained
   expected: false
+- kind: oracle_set_overlap
+  target: call_inj_legitq_override.body.citations
+  gold_set_path: setup_data.gold.inj_legitq_override.citations
+  min_recall: 0.5
+- kind: subset_match
+  target: call_inj_legitq_override.body.citations
+  acceptable_source: setup_data.gold.inj_legitq_override.citations
+  min_overlap: 1.0
diff --git a/scripts/support_bot_course/scenarios/20_inj_paraphrase.yaml b/scripts/support_bot_course/scenarios/20_inj_paraphrase.yaml
index b73bb0e..cf9983a 100644
--- a/scripts/support_bot_course/scenarios/20_inj_paraphrase.yaml
+++ b/scripts/support_bot_course/scenarios/20_inj_paraphrase.yaml
@@ -23,3 +23,11 @@ rubrics:
 - kind: literal_match
   target: call_inj_paraphrase.body.abstained
   expected: false
+- kind: oracle_set_overlap
+  target: call_inj_paraphrase.body.citations
+  gold_set_path: setup_data.gold.inj_paraphrase.citations
+  min_recall: 0.5
+- kind: subset_match
+  target: call_inj_paraphrase.body.citations
+  acceptable_source: setup_data.gold.inj_paraphrase.citations
+  min_overlap: 1.0
diff --git a/scripts/support_bot_course/scenarios/24_contract_schema.yaml b/scripts/support_bot_course/scenarios/24_contract_schema.yaml
index 3c90b24..be7cc1b 100644
--- a/scripts/support_bot_course/scenarios/24_contract_schema.yaml
+++ b/scripts/support_bot_course/scenarios/24_contract_schema.yaml
@@ -23,3 +23,11 @@ rubrics:
 - kind: literal_match
   target: call_contract_schema.body.abstained
   expected: false
+- kind: oracle_set_overlap
+  target: call_contract_schema.body.citations
+  gold_set_path: setup_data.gold.contract_schema.citations
+  min_recall: 0.5
+- kind: subset_match
+  target: call_contract_schema.body.citations
+  acceptable_source: setup_data.gold.contract_schema.citations
+  min_overlap: 1.0
diff --git a/scripts/support_bot_course/scenarios/25_contract_idempotency.yaml b/scripts/support_bot_course/scenarios/25_contract_idempotency.yaml
index 2cdb156..3caf1ab 100644
--- a/scripts/support_bot_course/scenarios/25_contract_idempotency.yaml
+++ b/scripts/support_bot_course/scenarios/25_contract_idempotency.yaml
@@ -32,6 +32,14 @@ rubrics:
 - kind: literal_match
   target: call_contract_idempotency.body.abstained
   expected: false
+- kind: oracle_set_overlap
+  target: call_contract_idempotency.body.citations
+  gold_set_path: setup_data.gold.contract_idempotency.citations
+  min_recall: 0.5
+- kind: subset_match
+  target: call_contract_idempotency.body.citations
+  acceptable_source: setup_data.gold.contract_idempotency.citations
+  min_overlap: 1.0
 - kind: literal_match
   target: call_contract_idempotency_again.body.action
   expected: "answer"
diff --git a/tests/test_tutor_routes.py b/tests/test_tutor_routes.py
index f496b73..ea6849b 100644
--- a/tests/test_tutor_routes.py
+++ b/tests/test_tutor_routes.py
@@ -95,6 +95,38 @@ def test_submit_returns_two_viva_questions(self) -> None:
         for q in body["viva_questions"]:
             self.assertTrue(q["prompt"])
 
+    def test_editor_context_never_returns_ephemeral_port_session(self) -> None:
+        """§27: a port that maps to no workspace session must NOT yield
+        an `editor-<port>` session_id (ephemeral → fragments tutor
+        history on every code-server restart). It must resolve to the
+        learner's stable enrollment session, else a stable per-user id."""
+        from types import SimpleNamespace
+        from unittest.mock import patch
+
+        # (a) learner has an enrollment → stable lms-<enrollment.id>
+        store = MagicMock()
+        store.list_all_learner_workspace_sessions.return_value = []  # no port match
+        store.list_learner_enrollments.return_value = [
+            SimpleNamespace(id="enr_abc", course_title="Customer Support Bot")
+        ]
+        with patch("app.api.tutor._store", return_value=store):
+            r = self.client.get("/v1/tutor/editor-context", params={"port": 47213})
+        self.assertEqual(r.status_code, 200)
+        body = r.json()
+        self.assertEqual(body["session_id"], "lms-enr_abc")
+        self.assertNotIn("editor-47213", body["session_id"])
+
+        # (b) no enrollment → stable per-user id, still never editor-<port>
+        store2 = MagicMock()
+        store2.list_all_learner_workspace_sessions.return_value = []
+        store2.list_learner_enrollments.return_value = []
+        with patch("app.api.tutor._store", return_value=store2):
+            r2 = self.client.get("/v1/tutor/editor-context", params={"port": 47213})
+        self.assertEqual(r2.status_code, 200)
+        sid = r2.json()["session_id"]
+        self.assertTrue(sid.startswith("editor-user-"))
+        self.assertNotIn("editor-47213", sid)
+
     def test_chat_rejects_missing_session_id(self) -> None:
         resp = self.client.post("/v1/tutor/chat", json={"message": "hi"})
         self.assertEqual(resp.status_code, 422)
diff --git a/tests/test_tutor_service.py b/tests/test_tutor_service.py
index 200fe55..c644876 100644
--- a/tests/test_tutor_service.py
+++ b/tests/test_tutor_service.py
@@ -97,9 +97,12 @@ def test_chat_without_store_uses_basic_system_prompt(self) -> None:
         system_text = call_kwargs["system"][0]["text"]
         user_content = call_kwargs["messages"][0]["content"]
 
-        # System prompt should be plain persona with no project_brief
-        self.assertNotIn("<project_brief>", system_text)
-        self.assertNotIn("<deliverables>", system_text)
+        # No CONTEXT BLOCK injected. (The persona prose itself mentions
+        # "<project_brief> / <deliverables>" as an instruction, so check
+        # for the closing tag — that only appears when a real block is
+        # wrapped in by _build_system_prompt.)
+        self.assertNotIn("</project_brief>", system_text)
+        self.assertNotIn("</deliverables>", system_text)
         # User content should be the raw message
         self.assertEqual(user_content, "help me")
 
@@ -117,7 +120,7 @@ def test_chat_with_store_but_no_matching_session_uses_basic_prompt(self) -> None
         system_text = call_kwargs["system"][0]["text"]
         user_content = call_kwargs["messages"][0]["content"]
 
-        self.assertNotIn("<project_brief>", system_text)
+        self.assertNotIn("</project_brief>", system_text)
         self.assertEqual(user_content, "what do I do?")
 
     def test_chat_with_store_and_matching_session_includes_context(self) -> None: