diff --git a/docs/superpowers/plans/2026-09-16-phase-1b-design-system-and-board.md b/docs/superpowers/plans/2026-09-16-phase-1b-design-system-and-board.md
index 60f55a4..aa16dbd 100644
--- a/docs/superpowers/plans/2026-09-16-phase-1b-design-system-and-board.md
+++ b/docs/superpowers/plans/2026-09-16-phase-1b-design-system-and-board.md
@@ -4,9 +4,9 @@
 
 **Goal:** Build the themed design system, the application shell, and a working Kanban board that the owner can drag cards around and a client manager can read and set priorities on.
 
-**Architecture:** Semantic CSS custom properties defined once per theme and exposed to Tailwind 4 through `@theme inline`, so no component ever hardcodes a colour. A server component loads a project's board using the signed-in user's own PocketBase token, which means the read rules from Plan 1a are the real boundary rather than a UI convention. Drag and drop is `@dnd-kit`, with the position arithmetic extracted into a pure, unit-tested module. The owner writes card moves straight to PocketBase; a client manager's edits go through the `/api/client/*` routes built in Plan 1a.
+**Architecture:** Semantic CSS custom properties defined once per theme and exposed to Tailwind 4 through `@theme inline`, so no component ever hardcodes a colour. A server component loads a project's board using the signed-in user's own PocketBase token, which means the read rules from Plan 1a are the real boundary rather than a UI convention. Drag and drop is `@dnd-kit`, with the position arithmetic extracted into a pure, unit-tested module. Every write goes through a server route, because Plan 1a's auth token lives in an httpOnly cookie the browser SDK cannot read — the owner's card moves through `/api/owner/*`, the client manager's two editable fields through the `/api/client/*` routes already built.
 
-**Tech Stack:** Next.js 16 · React 19 · Tailwind 4 · Radix primitives · @dnd-kit · PocketBase realtime · vitest
+**Tech Stack:** Next.js 16 · React 19 · Tailwind 4 · Radix primitives · @dnd-kit · vitest
 
 **Spec:** `docs/superpowers/specs/2026-09-16-client-board-phase-1-design.md` §8
 
@@ -57,7 +57,7 @@ src/
 │   │   ├── board-column.tsx
 │   │   ├── card-tile.tsx
 │   │   ├── client-card-controls.tsx        # priority + date, client only
-│   │   └── use-board-realtime.ts
+│   │   └── use-refresh-on-focus.ts
 │   └── ui/
 │       ├── pill.tsx
 │       ├── icon-button.tsx
diff --git a/src/app/api/client/cards/[id]/comments/route.ts b/src/app/api/client/cards/[id]/comments/route.ts
new file mode 100644
index 0000000..705c106
--- /dev/null
+++ b/src/app/api/client/cards/[id]/comments/route.ts
@@ -0,0 +1,85 @@
+import { getAdminPb } from "@/lib/pb/admin";
+import { requireSession } from "@/lib/auth/session";
+import {
+  AccessError,
+  assertClientOwnsProject,
+  canWriteClientFields,
+} from "@/lib/auth/access";
+import { jsonError, jsonOk } from "@/lib/http/json";
+import type { CardRecord, CommentRecord, ProjectRecord } from "@/lib/pb/types";
+
+/**
+ * POST /api/client/cards/:id/comments
+ *
+ * The body is stored as raw markdown and is never trusted. Plan 1b renders it
+ * with react-markdown and no raw-HTML plugin; nothing may pass it to
+ * dangerouslySetInnerHTML.
+ */
+export async function POST(
+  request: Request,
+  context: { params: Promise<{ id: string }> }
+): Promise<Response> {
+  try {
+    const session = await requireSession();
+    const { id } = await context.params;
+
+    let body: unknown;
+    try {
+      body = await request.json();
+    } catch {
+      return jsonError("Invalid request body", 400);
+    }
+
+    const text =
+      typeof body === "object" && body !== null
+        ? (body as Record<string, unknown>).body
+        : undefined;
+
+    if (typeof text !== "string" || !text.trim()) {
+      return jsonError("A comment body is required", 400);
+    }
+
+    const pb = await getAdminPb();
+
+    let card: CardRecord;
+    try {
+      card = await pb.collection("cards").getOne<CardRecord>(id);
+    } catch {
+      return jsonError("Card not found", 404);
+    }
+
+    const project = await pb
+      .collection("projects")
+      .getOne<ProjectRecord>(card.project);
+
+    assertClientOwnsProject(session, project);
+
+    if (!canWriteClientFields(session, project.client)) {
+      return jsonError("Card not found", 404);
+    }
+
+    const comment = await pb.collection("comments").create<CommentRecord>({
+      card: id,
+      author: session.userId,
+      body: text.trim().slice(0, 20000),
+    });
+
+    await pb.collection("activity").create({
+      project: card.project,
+      card: id,
+      actor: session.userId,
+      action: "comment_added",
+      field: "",
+      old_value: "",
+      new_value: "",
+    });
+
+    return jsonOk({ comment: { id: comment.id } }, 201);
+  } catch (error) {
+    if (error instanceof AccessError) {
+      return jsonError(error.message, error.status);
+    }
+    console.error("[client-comment] unexpected error", error);
+    return jsonError("Something went wrong", 500);
+  }
+}
\ No newline at end of file
diff --git a/src/app/api/client/cards/route.ts b/src/app/api/client/cards/route.ts
new file mode 100644
index 0000000..6336746
--- /dev/null
+++ b/src/app/api/client/cards/route.ts
@@ -0,0 +1,123 @@
+import { getAdminPb } from "@/lib/pb/admin";
+import { requireSession } from "@/lib/auth/session";
+import {
+  AccessError,
+  assertClientOwnsProject,
+  canWriteClientFields,
+} from "@/lib/auth/access";
+import { pickClientCardCreate } from "@/lib/cards/client-patch";
+import { positionBetween } from "@/lib/ordering/fractional";
+import { jsonError, jsonOk } from "@/lib/http/json";
+import type { CardRecord, ColumnRecord, ProjectRecord } from "@/lib/pb/types";
+
+/**
+ * POST /api/client/cards — a client manager proposes a new card.
+ *
+ * The destination column, priority and accepted flag are chosen here, never
+ * taken from the request. A card always lands in the project's Inbox at
+ * medium priority with accepted=false, whatever the body asks for. The owner
+ * accepts it by dragging it out, which is what sets accepted=true.
+ */
+export async function POST(request: Request): Promise<Response> {
+  try {
+    const session = await requireSession();
+
+    let body: unknown;
+    try {
+      body = await request.json();
+    } catch {
+      return jsonError("Invalid request body", 400);
+    }
+
+    const projectId =
+      typeof body === "object" && body !== null
+        ? (body as Record<string, unknown>).project
+        : undefined;
+
+    if (typeof projectId !== "string" || !projectId) {
+      return jsonError("A project id is required", 400);
+    }
+
+    const pb = await getAdminPb();
+
+    let project: ProjectRecord;
+    try {
+      project = await pb
+        .collection("projects")
+        .getOne<ProjectRecord>(projectId);
+    } catch {
+      return jsonError("Project not found", 404);
+    }
+
+    assertClientOwnsProject(session, project);
+
+    if (!canWriteClientFields(session, project.client)) {
+      return jsonError("Project not found", 404);
+    }
+
+    const { input, dropped } = pickClientCardCreate(body);
+
+    if (dropped.length > 0) {
+      console.warn(
+        `[client-create] user=${session.userId} project=${projectId} dropped=${dropped.join(",")}`
+      );
+    }
+
+    if (!input) {
+      return jsonError("A title is required", 400);
+    }
+
+    const inbox = await pb
+      .collection("columns")
+      .getFirstListItem<ColumnRecord>(
+        `project = "${projectId}" && is_inbox = true`
+      )
+      .catch(() => null);
+
+    if (!inbox) {
+      // The column invariants in src/lib/columns/seed.ts should make this
+      // impossible. If it happens, the project's columns are corrupt and
+      // silently inventing a destination would hide that.
+      console.error(`[client-create] project ${projectId} has no inbox column`);
+      return jsonError("This project cannot accept new cards", 409);
+    }
+
+    const last = await pb
+      .collection("cards")
+      .getFirstListItem<CardRecord>(`column = "${inbox.id}"`, {
+        sort: "-position",
+      })
+      .catch(() => null);
+
+    const card = await pb.collection("cards").create<CardRecord>({
+      project: projectId,
+      column: inbox.id,
+      title: input.title,
+      description: input.description,
+      position: positionBetween(last ? last.position : null, null),
+      priority: "medium",
+      created_by: session.userId,
+      created_by_role: "client",
+      accepted: false,
+      archived: false,
+    });
+
+    await pb.collection("activity").create({
+      project: projectId,
+      card: card.id,
+      actor: session.userId,
+      action: "card_created",
+      field: "",
+      old_value: "",
+      new_value: card.title,
+    });
+
+    return jsonOk({ card: { id: card.id, title: card.title } }, 201);
+  } catch (error) {
+    if (error instanceof AccessError) {
+      return jsonError(error.message, error.status);
+    }
+    console.error("[client-create] unexpected error", error);
+    return jsonError("Something went wrong", 500);
+  }
+}
\ No newline at end of file