diff --git a/apps/web/__tests__/lib/auth.test.ts b/apps/web/__tests__/lib/auth.test.ts
new file mode 100644
index 0000000..0de01b6
--- /dev/null
+++ b/apps/web/__tests__/lib/auth.test.ts
@@ -0,0 +1,83 @@
+/**
+ * Unit tests for resolveActiveDomain helper in lib/auth.ts.
+ * Tests both branches: existing domain returned, and auto-creation of "Personal" domain.
+ */
+
+import { describe, it, expect, jest, beforeEach } from '@jest/globals';
+
+// Mock the database module
+const mockDb = {
+  select: jest.fn(),
+  insert: jest.fn(),
+};
+const mockDomains = {};
+
+jest.mock('@project-e/db', () => ({
+  db: mockDb,
+  domains: mockDomains,
+}));
+
+// Mock next-auth
+jest.mock('next-auth', () => ({
+  getServerSession: jest.fn(),
+}));
+
+// Mock next-auth config
+jest.mock('@/lib/auth-config', () => ({
+  authOptions: {},
+}));
+
+describe('resolveActiveDomain', () => {
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  it('should return the user\'s first existing domain without creating one', async () => {
+    const { resolveActiveDomain } = await import('@/lib/auth');
+
+    const mockUser = { id: 'user-1', email: 'test@example.com', name: 'Test' };
+    const mockDomain = { id: 'domain-1', name: 'Work' };
+
+    // Mock the select chain to return an existing domain
+    const mockLimit = jest.fn().mockResolvedValue([mockDomain]);
+    const mockOrderBy = jest.fn().mockReturnValue({ limit: mockLimit });
+    const mockWhere = jest.fn().mockReturnValue({ orderBy: mockOrderBy });
+    const mockFrom = jest.fn().mockReturnValue({ where: mockWhere });
+    mockDb.select.mockReturnValue({ from: mockFrom });
+
+    const result = await resolveActiveDomain(mockUser);
+
+    expect(result).toEqual({ id: 'domain-1', name: 'Work', created: false });
+    expect(mockDb.select).toHaveBeenCalledWith({ id: expect.anything(), name: expect.anything() });
+    expect(mockDb.insert).not.toHaveBeenCalled();
+  });
+
+  it('should create a "Personal" domain when the user has none', async () => {
+    const { resolveActiveDomain } = await import('@/lib/auth');
+
+    const mockUser = { id: 'user-2', email: 'new@example.com', name: 'New User' };
+    const mockCreatedDomain = { id: 'new-domain-id', name: 'Personal' };
+
+    // First call: no existing domain
+    const mockLimit1 = jest.fn().mockResolvedValue([]);
+    const mockOrderBy1 = jest.fn().mockReturnValue({ limit: mockLimit1 });
+    const mockWhere1 = jest.fn().mockReturnValue({ orderBy: mockOrderBy1 });
+    const mockFrom1 = jest.fn().mockReturnValue({ where: mockWhere1 });
+    mockDb.select.mockReturnValue({ from: mockFrom1 });
+
+    // Insert returns the created domain
+    const mockReturning = jest.fn().mockResolvedValue([mockCreatedDomain]);
+    const mockValues = jest.fn().mockReturnValue({ returning: mockReturning });
+    mockDb.insert.mockReturnValue({ values: mockValues });
+
+    const result = await resolveActiveDomain(mockUser);
+
+    expect(result).toEqual({ id: 'new-domain-id', name: 'Personal', created: true });
+    expect(mockDb.insert).toHaveBeenCalled();
+    expect(mockValues).toHaveBeenCalledWith(expect.objectContaining({
+      ownerId: 'user-2',
+      name: 'Personal',
+      sortOrder: 0,
+    }));
+  });
+});
diff --git a/apps/web/app/(dashboard)/canvas/page.tsx b/apps/web/app/(dashboard)/canvas/page.tsx
index 7207141..988b6f4 100644
--- a/apps/web/app/(dashboard)/canvas/page.tsx
+++ b/apps/web/app/(dashboard)/canvas/page.tsx
@@ -399,7 +399,6 @@ export default function CanvasPage() {
         body: JSON.stringify({
           name: 'New canvas',
           mode: 'freeform',
-          domain: 'personal',
         }),
       });
       if (!res.ok) throw new Error('Unable to create canvas.');
diff --git a/apps/web/app/api/agents/route.ts b/apps/web/app/api/agents/route.ts
index c3de684..9805292 100644
--- a/apps/web/app/api/agents/route.ts
+++ b/apps/web/app/api/agents/route.ts
@@ -4,7 +4,7 @@
 // See AGENTS.md for full rules.
 
 import { NextRequest, NextResponse } from 'next/server';
-import { withAuth, createErrorResponse } from '@/lib/auth';
+import { withAuth, createErrorResponse, resolveActiveDomain } from '@/lib/auth';
 import { createPocketBaseClient } from '@/lib/pocketbase';
 import { createAgentSchema } from '@project-e/shared';
 import { z } from 'zod';
@@ -33,10 +33,13 @@ export const GET = withAuth(async (request: NextRequest, _user) => {
 });
 
 // POST /api/agents — Create an agent with auto-generated API key
-export const POST = withAuth(async (request: NextRequest, _user) => {
+export const POST = withAuth(async (request: NextRequest, user) => {
   try {
     const body = await request.json();
-    const data = createAgentSchema.parse(body);
+    const data = createAgentSchema.parse({
+      ...body,
+      domain: body.domain || (await resolveActiveDomain(user)).id,
+    });
 
     const pb = createPocketBaseClient();
     const agent = await pb.collection('agents').create({
diff --git a/apps/web/app/api/canvases/route.ts b/apps/web/app/api/canvases/route.ts
index d216266..c4b8e79 100644
--- a/apps/web/app/api/canvases/route.ts
+++ b/apps/web/app/api/canvases/route.ts
@@ -4,7 +4,7 @@
 // See AGENTS.md for full rules.
 
 import { NextRequest, NextResponse } from 'next/server';
-import { withAuth, createErrorResponse } from '@/lib/auth';
+import { withAuth, createErrorResponse, resolveActiveDomain } from '@/lib/auth';
 import { createPocketBaseClient } from '@/lib/pocketbase';
 import { createCanvasSchema } from '@project-e/shared';
 import { z } from 'zod';
@@ -33,10 +33,13 @@ export const GET = withAuth(async (request: NextRequest, _user) => {
 });
 
 // POST /api/canvases — Create a canvas
-export const POST = withAuth(async (request: NextRequest, _user) => {
+export const POST = withAuth(async (request: NextRequest, user) => {
   try {
     const body = await request.json();
-    const data = createCanvasSchema.parse(body);
+    const data = createCanvasSchema.parse({
+      ...body,
+      domain: body.domain || (await resolveActiveDomain(user)).id,
+    });
 
     const pb = createPocketBaseClient();
     const canvas = await pb.collection('canvases').create(data);
diff --git a/apps/web/app/api/domains/route.ts b/apps/web/app/api/domains/route.ts
index fcc9e59..eadc193 100644
--- a/apps/web/app/api/domains/route.ts
+++ b/apps/web/app/api/domains/route.ts
@@ -4,7 +4,7 @@
 // See AGENTS.md for full rules.
 
 import { NextRequest, NextResponse } from 'next/server';
-import { withAuth, createErrorResponse } from '@/lib/auth';
+import { withAuth, createErrorResponse, resolveActiveDomain } from '@/lib/auth';
 import { db, domains } from '@project-e/db';
 import { and, asc, desc, eq, ilike, or, sql } from 'drizzle-orm';
 import { z } from 'zod';
@@ -18,7 +18,7 @@ const createDomainSchema = z.object({
 });
 
 // GET /api/domains — List domains with filtering, sorting, pagination
-export const GET = withAuth(async (request: NextRequest, _user) => {
+export const GET = withAuth(async (request: NextRequest, user) => {
   const { searchParams } = new URL(request.url);
   const page = Math.max(1, parseInt(searchParams.get('page') || '1'));
   const perPage = Math.min(100, Math.max(1, parseInt(searchParams.get('perPage') || '50')));
@@ -39,8 +39,8 @@ export const GET = withAuth(async (request: NextRequest, _user) => {
     ? asc(sortColumns[sortField] || domains.sortOrder)
     : desc(sortColumns[sortField] || domains.sortOrder);
 
-  // Build where clause
-  const conditions: any[] = [];
+  // Build where clause — filter by owner
+  const conditions: any[] = [eq(domains.ownerId, user.id)];
   if (filter) {
     conditions.push(
       or(
@@ -64,7 +64,31 @@ export const GET = withAuth(async (request: NextRequest, _user) => {
       .where(and(...conditions)),
   ]);
 
-  const totalItems = Number(countResult[0]?.count || 0);
+  let totalItems = Number(countResult[0]?.count || 0);
+
+  // If user has no domains, auto-create a default "Personal" domain
+  if (totalItems === 0) {
+    const active = await resolveActiveDomain(user);
+    // Re-fetch to include the newly created domain
+    const [newItems, newCount] = await Promise.all([
+      db.select()
+        .from(domains)
+        .where(eq(domains.ownerId, user.id))
+        .orderBy(orderBy)
+        .limit(perPage)
+        .offset(offset),
+      db.select({ count: sql<number>`count(*)` })
+        .from(domains)
+        .where(eq(domains.ownerId, user.id)),
+    ]);
+    return NextResponse.json({
+      items: newItems,
+      totalItems: Number(newCount[0]?.count || 0),
+      totalPages: Math.ceil(Number(newCount[0]?.count || 0) / perPage),
+      page,
+      perPage,
+    });
+  }
 
   return NextResponse.json({
     items,
@@ -76,7 +100,7 @@ export const GET = withAuth(async (request: NextRequest, _user) => {
 });
 
 // POST /api/domains — Create a domain
-export const POST = withAuth(async (request: NextRequest, _user) => {
+export const POST = withAuth(async (request: NextRequest, user) => {
   try {
     const body = await request.json();
     const data = createDomainSchema.parse(body);
@@ -88,6 +112,7 @@ export const POST = withAuth(async (request: NextRequest, _user) => {
         color: data.color || null,
         icon: data.icon || null,
         parentId: data.parentId || null,
+        ownerId: user.id,
       })
       .returning();
 
diff --git a/apps/web/app/api/habits/route.ts b/apps/web/app/api/habits/route.ts
index aa30f29..a0153c5 100644
--- a/apps/web/app/api/habits/route.ts
+++ b/apps/web/app/api/habits/route.ts
@@ -4,7 +4,7 @@
 // See AGENTS.md for full rules.
 
 import { NextRequest, NextResponse } from 'next/server';
-import { withAuth, createErrorResponse } from '@/lib/auth';
+import { withAuth, createErrorResponse, resolveActiveDomain } from '@/lib/auth';
 import { recordActivity } from '@/lib/activity';
 import { db, habits, habitTags, tags as tagsTable } from '@project-e/db';
 import { and, asc, desc, eq, ilike, inArray, isNull, or, sql } from 'drizzle-orm';
@@ -25,13 +25,17 @@ const createHabitSchema = z.object({
 });
 
 // GET /api/habits — List habits with filtering, sorting, pagination
-export const GET = withAuth(async (request: NextRequest, _user) => {
+export const GET = withAuth(async (request: NextRequest, user) => {
   const { searchParams } = new URL(request.url);
   const page = Math.max(1, parseInt(searchParams.get('page') || '1'));
   const perPage = Math.min(100, Math.max(1, parseInt(searchParams.get('perPage') || '50')));
   const filter = searchParams.get('filter') || undefined;
   const sort = searchParams.get('sort') || '-created';
-  const domainId = searchParams.get('domain') || undefined;
+  let domainId = searchParams.get('domain') || undefined;
+  if (!domainId) {
+    const active = await resolveActiveDomain(user);
+    domainId = active.id;
+  }
 
   const sortDir = sort.startsWith('-') ? 'desc' : 'asc';
   const sortField = sort.replace(/^-/, '');
@@ -81,7 +85,10 @@ export const GET = withAuth(async (request: NextRequest, _user) => {
 export const POST = withAuth(async (request: NextRequest, user) => {
   try {
     const body = await request.json();
-    const data = createHabitSchema.parse(body);
+    const data = createHabitSchema.parse({
+      ...body,
+      domain: body.domain || (await resolveActiveDomain(user)).id,
+    });
 
     const [habit] = await db.insert(habits).values({
       name: data.name,
diff --git a/apps/web/app/api/projects/route.ts b/apps/web/app/api/projects/route.ts
index 807c0d4..f0b542d 100644
--- a/apps/web/app/api/projects/route.ts
+++ b/apps/web/app/api/projects/route.ts
@@ -4,7 +4,7 @@
 // See AGENTS.md for full rules.
 
 import { NextRequest, NextResponse } from 'next/server';
-import { withAuth, createErrorResponse } from '@/lib/auth';
+import { withAuth, createErrorResponse, resolveActiveDomain } from '@/lib/auth';
 import { recordActivity } from '@/lib/activity';
 import { db, projects, projectTags, tags as tagsTable } from '@project-e/db';
 import { and, asc, desc, eq, ilike, inArray, isNull, or, sql } from 'drizzle-orm';
@@ -24,13 +24,17 @@ const createProjectSchema = z.object({
 });
 
 // GET /api/projects — List projects with filtering, sorting, pagination
-export const GET = withAuth(async (request: NextRequest, _user) => {
+export const GET = withAuth(async (request: NextRequest, user) => {
   const { searchParams } = new URL(request.url);
   const page = Math.max(1, parseInt(searchParams.get('page') || '1'));
   const perPage = Math.min(100, Math.max(1, parseInt(searchParams.get('perPage') || '50')));
   const filter = searchParams.get('filter') || undefined;
   const sort = searchParams.get('sort') || '-created';
-  const domainId = searchParams.get('domain') || undefined;
+  let domainId = searchParams.get('domain') || undefined;
+  if (!domainId) {
+    const active = await resolveActiveDomain(user);
+    domainId = active.id;
+  }
 
   const sortDir = sort.startsWith('-') ? 'desc' : 'asc';
   const sortField = sort.replace(/^-/, '');
@@ -79,7 +83,10 @@ export const GET = withAuth(async (request: NextRequest, _user) => {
 export const POST = withAuth(async (request: NextRequest, user) => {
   try {
     const body = await request.json();
-    const data = createProjectSchema.parse(body);
+    const data = createProjectSchema.parse({
+      ...body,
+      domain: body.domain || (await resolveActiveDomain(user)).id,
+    });
 
     const [project] = await db.insert(projects).values({
       name: data.name,
diff --git a/apps/web/app/api/quick-capture/route.ts b/apps/web/app/api/quick-capture/route.ts
new file mode 100644
index 0000000..0775011
--- /dev/null
+++ b/apps/web/app/api/quick-capture/route.ts
@@ -0,0 +1,110 @@
+// AGENT INSTRUCTION: After every write (INSERT/UPDATE/DELETE), you MUST:
+// 1. Insert activity feed entry
+// 2. Call pg.notify('project_e_events', JSON.stringify({ type, action, id, workspace_id }))
+// See AGENTS.md for full rules.
+
+import { NextRequest, NextResponse } from 'next/server';
+import { withAuth, createErrorResponse, resolveActiveDomain } from '@/lib/auth';
+import { recordActivity } from '@/lib/activity';
+import { db, tasks, habits, notes, projects } from '@project-e/db';
+import { z } from 'zod';
+
+const quickCaptureSchema = z.object({
+  type: z.enum(['task', 'habit', 'note', 'project']),
+  text: z.string().min(1, 'Text is required'),
+  description: z.string().optional().nullable(),
+  priority: z.enum(['low', 'medium', 'high', 'urgent']).optional().default('medium'),
+  domain: z.string().optional(),
+});
+
+// POST /api/quick-capture — Create an entity from quick text input
+// Forwards to the appropriate create logic after resolving the active domain.
+export const POST = withAuth(async (request: NextRequest, user) => {
+  try {
+    const body = await request.json();
+    const data = quickCaptureSchema.parse(body);
+    const domainId = data.domain || (await resolveActiveDomain(user)).id;
+
+    let result;
+
+    switch (data.type) {
+      case 'task': {
+        const [task] = await db.insert(tasks).values({
+          title: data.text,
+          description: data.description ?? null,
+          domainId,
+          priority: data.priority,
+        }).returning();
+        result = task;
+        await recordActivity({
+          actor: user.name,
+          action: 'created',
+          entityType: 'task',
+          entityId: task.id,
+          changes: { title: task.title },
+          workspaceId: domainId,
+        });
+        break;
+      }
+      case 'habit': {
+        const [habit] = await db.insert(habits).values({
+          name: data.text,
+          description: data.description ?? null,
+          domainId,
+        }).returning();
+        result = habit;
+        await recordActivity({
+          actor: user.name,
+          action: 'created',
+          entityType: 'habit',
+          entityId: habit.id,
+          changes: { name: habit.name },
+          workspaceId: domainId,
+        });
+        break;
+      }
+      case 'note': {
+        const [note] = await db.insert(notes).values({
+          title: data.text,
+          content: data.description ?? null,
+          domainId,
+        }).returning();
+        result = note;
+        await recordActivity({
+          actor: user.name,
+          action: 'created',
+          entityType: 'note',
+          entityId: note.id,
+          changes: { title: note.title },
+          workspaceId: domainId,
+        });
+        break;
+      }
+      case 'project': {
+        const [project] = await db.insert(projects).values({
+          name: data.text,
+          description: data.description ?? null,
+          domainId,
+        }).returning();
+        result = project;
+        await recordActivity({
+          actor: user.name,
+          action: 'created',
+          entityType: 'project',
+          entityId: project.id,
+          changes: { name: project.name },
+          workspaceId: domainId,
+        });
+        break;
+      }
+    }
+
+    return NextResponse.json(result, { status: 201 });
+  } catch (error) {
+    if (error instanceof z.ZodError) {
+      return createErrorResponse('VALIDATION_ERROR', 'Invalid input', 400, error.issues);
+    }
+    console.error('[quick-capture POST] error:', error);
+    return createErrorResponse('INTERNAL_ERROR', 'Failed to create', 500);
+  }
+});
diff --git a/apps/web/app/api/search/route.ts b/apps/web/app/api/search/route.ts
index 7598f51..5a315c4 100644
--- a/apps/web/app/api/search/route.ts
+++ b/apps/web/app/api/search/route.ts
@@ -4,7 +4,7 @@
 // See AGENTS.md for full rules.
 
 import { NextRequest, NextResponse } from 'next/server';
-import { withAuth, createErrorResponse } from '@/lib/auth';
+import { withAuth, createErrorResponse, resolveActiveDomain } from '@/lib/auth';
 import { searchEntities } from '@/lib/search-service';
 
 // GET /api/search?q=&type=&domain=&limit=&offset=
@@ -13,7 +13,11 @@ export const GET = withAuth(async (request: NextRequest, user) => {
   const { searchParams } = new URL(request.url);
   const q = (searchParams.get('q') || '').trim();
   const types = searchParams.get('types')?.split(',').filter(Boolean) || ['task', 'note', 'project', 'habit', 'domain'];
-  const domain = searchParams.get('domain') || undefined;
+  let domain = searchParams.get('domain') || undefined;
+  if (!domain) {
+    const active = await resolveActiveDomain(user);
+    domain = active.id;
+  }
   const limit = Math.max(1, Math.min(50, parseInt(searchParams.get('limit') || '20')));
   const offset = Math.max(0, parseInt(searchParams.get('offset') || '0'));
 
diff --git a/apps/web/app/api/tasks/route.ts b/apps/web/app/api/tasks/route.ts
index 53adbd7..3a00c21 100644
--- a/apps/web/app/api/tasks/route.ts
+++ b/apps/web/app/api/tasks/route.ts
@@ -4,7 +4,7 @@
 // See AGENTS.md for full rules.
 
 import { NextRequest, NextResponse } from 'next/server';
-import { withAuth, createErrorResponse } from '@/lib/auth';
+import { withAuth, createErrorResponse, resolveActiveDomain } from '@/lib/auth';
 import { recordActivity } from '@/lib/activity';
 import { db, tasks, taskTags, tags as tagsTable } from '@project-e/db';
 import { and, asc, desc, eq, ilike, inArray, isNull, or, sql } from 'drizzle-orm';
@@ -29,13 +29,17 @@ const createTaskSchema = z.object({
 });
 
 // GET /api/tasks — List tasks with filtering, sorting, pagination
-export const GET = withAuth(async (request: NextRequest, _user) => {
+export const GET = withAuth(async (request: NextRequest, user) => {
   const { searchParams } = new URL(request.url);
   const page = Math.max(1, parseInt(searchParams.get('page') || '1'));
   const perPage = Math.min(100, Math.max(1, parseInt(searchParams.get('perPage') || '50')));
   const filter = searchParams.get('filter') || undefined;
   const sort = searchParams.get('sort') || '-created';
-  const domainId = searchParams.get('domain') || undefined;
+  let domainId = searchParams.get('domain') || undefined;
+  if (!domainId) {
+    const active = await resolveActiveDomain(user);
+    domainId = active.id;
+  }
 
   const sortDir = sort.startsWith('-') ? 'desc' : 'asc';
   const sortField = sort.replace(/^-/, '');
@@ -92,7 +96,10 @@ export const GET = withAuth(async (request: NextRequest, _user) => {
 export const POST = withAuth(async (request: NextRequest, user) => {
   try {
     const body = await request.json();
-    const data = createTaskSchema.parse(body);
+    const data = createTaskSchema.parse({
+      ...body,
+      domain: body.domain || (await resolveActiveDomain(user)).id,
+    });
 
     const [task] = await db.insert(tasks).values({
       title: data.title,
diff --git a/apps/web/lib/auth.ts b/apps/web/lib/auth.ts
index a051833..05bead9 100644
--- a/apps/web/lib/auth.ts
+++ b/apps/web/lib/auth.ts
@@ -2,7 +2,7 @@ import { NextRequest, NextResponse } from 'next/server';
 import { getServerSession } from 'next-auth';
 import { authOptions } from './auth-config';
 import { db, domains } from '@project-e/db';
-import { eq } from 'drizzle-orm';
+import { asc, eq } from 'drizzle-orm';
 
 export interface AuthUser {
   id: string;
@@ -56,6 +56,34 @@ export async function requireWorkspaceAccess(workspaceId: string): Promise<void>
   }
 }
 
+/**
+ * Resolve the user's active workspace/domain. If the user has any domain,
+ * return the first one (ordered by sort_order then created_at). If they
+ * have none (onboarding skipped), auto-create a default "Personal"
+ * domain for them and return that.
+ *
+ * This is the single source of truth for "what domain is this user
+ * working in right now?" -- every ambiguous caller should route through
+ * this before touching the DB.
+ */
+export async function resolveActiveDomain(user: { id: string; email: string; name?: string | null }): Promise<{ id: string; name: string; created: boolean }> {
+  const [existing] = await db
+    .select({ id: domains.id, name: domains.name })
+    .from(domains)
+    .where(eq(domains.ownerId, user.id))
+    .orderBy(asc(domains.sortOrder), asc(domains.createdAt))
+    .limit(1);
+  if (existing) return { ...existing, created: false };
+  const slug = 'personal-' + user.id.slice(0, 8);
+  const [created] = await db.insert(domains).values({
+    ownerId: user.id,
+    name: 'Personal',
+    slug: slug,
+    sortOrder: 0,
+  }).returning({ id: domains.id, name: domains.name });
+  return { ...created, created: true };
+}
+
 /**
  * Auth middleware for API routes
  * Wraps a route handler and ensures authentication
diff --git a/drizzle/0004_add_owner_id_to_domains.sql b/drizzle/0004_add_owner_id_to_domains.sql
new file mode 100644
index 0000000..f2b33c8
--- /dev/null
+++ b/drizzle/0004_add_owner_id_to_domains.sql
@@ -0,0 +1,3 @@
+ALTER TABLE "domains" ADD COLUMN "owner_id" uuid REFERENCES "public"."users"("id") ON DELETE cascade ON UPDATE no action;
+--> statement-breakpoint
+CREATE INDEX "domains_owner_id_idx" ON "domains" USING btree ("owner_id");
diff --git a/packages/db/src/schema.ts b/packages/db/src/schema.ts
index 5ebf1a5..82b87de 100644
--- a/packages/db/src/schema.ts
+++ b/packages/db/src/schema.ts
@@ -57,6 +57,7 @@ export const domains = pgTable(
     slug: text('slug').notNull().unique(),
     color: text('color'),
     icon: text('icon'),
+    ownerId: uuid('owner_id').references(() => users.id, { onDelete: 'cascade' }),
     parentId: uuid('parent_id').references((): any => domains.id, { onDelete: 'set null' }),
     sortOrder: integer('sort_order').default(0),
     customFields: jsonb('custom_fields').$type<Record<string, unknown>>().default({}),