diff --git a/packages/api/src/__tests__/assistant-tools-master-data-blueprints-rate-cards.test.ts b/packages/api/src/__tests__/assistant-tools-master-data-blueprints-rate-cards.test.ts
new file mode 100644
index 0000000..0cb6df1
--- /dev/null
+++ b/packages/api/src/__tests__/assistant-tools-master-data-blueprints-rate-cards.test.ts
@@ -0,0 +1,145 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { PermissionKey, SystemRole } from "@capakraken/shared";
+
+vi.mock("@capakraken/application", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@capakraken/application")>();
+  return {
+    ...actual,
+    countPlanningEntries: vi.fn().mockResolvedValue({ countsByRoleId: new Map() }),
+    getDashboardBudgetForecast: vi.fn().mockResolvedValue([]),
+    getDashboardPeakTimes: vi.fn().mockResolvedValue([]),
+    listAssignmentBookings: vi.fn().mockResolvedValue([]),
+  };
+});
+
+import { countPlanningEntries } from "@capakraken/application";
+import { executeTool } from "../router/assistant-tools.js";
+import { createToolContext } from "./assistant-tools-master-data-read-test-helpers.js";
+
+describe("assistant master data blueprint and rate-card read tools", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    vi.mocked(countPlanningEntries).mockResolvedValue({ countsByRoleId: new Map() });
+  });
+
+  it("routes blueprint and rate card reads through their backing routers", async () => {
+    const db = {
+      blueprint: {
+        findMany: vi.fn().mockResolvedValue([
+          {
+            id: "bp_project",
+            name: "Project Default",
+            _count: { projects: 3 },
+          },
+        ]),
+        findUnique: vi.fn().mockResolvedValue({
+          id: "bp_project",
+          name: "Project Default",
+          fieldDefs: [{ key: "market", type: "text" }],
+          rolePresets: [{ role: "Consulting", share: 0.5 }],
+        }),
+      },
+      rateCard: {
+        findMany: vi.fn().mockResolvedValue([
+          {
+            id: "rc_2026",
+            name: "Standard 2026",
+            effectiveFrom: new Date("2026-01-01T00:00:00.000Z"),
+            effectiveTo: null,
+            _count: { lines: 12 },
+            client: null,
+          },
+        ]),
+      },
+    };
+    const ctx = createToolContext(db, {
+      userRole: SystemRole.ADMIN,
+      permissions: [PermissionKey.VIEW_PLANNING, PermissionKey.VIEW_COSTS],
+    });
+
+    const blueprintsResult = await executeTool("list_blueprints", "{}", ctx);
+    const blueprintResult = await executeTool(
+      "get_blueprint",
+      JSON.stringify({ identifier: "bp_project" }),
+      ctx,
+    );
+    const rateCardsResult = await executeTool(
+      "list_rate_cards",
+      JSON.stringify({ query: "Standard", limit: 10 }),
+      ctx,
+    );
+
+    expect(db.blueprint.findMany).toHaveBeenCalledWith({
+      select: {
+        id: true,
+        name: true,
+        _count: { select: { projects: true } },
+      },
+      orderBy: { name: "asc" },
+    });
+    expect(db.blueprint.findUnique).toHaveBeenCalledWith({
+      where: { id: "bp_project" },
+    });
+    expect(db.rateCard.findMany).toHaveBeenCalledWith({
+      where: {
+        isActive: true,
+        name: { contains: "Standard", mode: "insensitive" },
+      },
+      include: {
+        _count: { select: { lines: true } },
+        client: { select: { id: true, name: true, code: true } },
+      },
+      orderBy: [{ isActive: "desc" }, { effectiveFrom: "desc" }, { name: "asc" }],
+    });
+
+    expect(JSON.parse(blueprintsResult.content)).toEqual([
+      {
+        id: "bp_project",
+        name: "Project Default",
+        projectCount: 3,
+      },
+    ]);
+    expect(JSON.parse(blueprintResult.content)).toEqual(
+      expect.objectContaining({
+        id: "bp_project",
+        name: "Project Default",
+        fieldDefs: [{ key: "market", type: "text" }],
+        rolePresets: [{ role: "Consulting", share: 0.5 }],
+      }),
+    );
+    expect(JSON.parse(rateCardsResult.content)).toEqual([
+      {
+        id: "rc_2026",
+        name: "Standard 2026",
+        effectiveFrom: "2026-01-01",
+        effectiveTo: null,
+        lineCount: 12,
+      },
+    ]);
+  });
+
+  it("returns a stable assistant error when a blueprint cannot be resolved for read access", async () => {
+    const ctx = createToolContext(
+      {
+        blueprint: {
+          findUnique: vi.fn().mockResolvedValue(null),
+          findFirst: vi.fn().mockResolvedValue(null),
+        },
+      },
+      {
+        userRole: SystemRole.ADMIN,
+        permissions: [PermissionKey.VIEW_PLANNING],
+      },
+    );
+
+    const result = await executeTool(
+      "get_blueprint",
+      JSON.stringify({ identifier: "Missing Blueprint" }),
+      ctx,
+    );
+
+    expect(JSON.parse(result.content)).toEqual({
+      error: "Blueprint not found: Missing Blueprint",
+    });
+  });
+});
diff --git a/packages/api/src/__tests__/assistant-tools-master-data-calculation-rules-read.test.ts b/packages/api/src/__tests__/assistant-tools-master-data-calculation-rules-read.test.ts
new file mode 100644
index 0000000..a5013c2
--- /dev/null
+++ b/packages/api/src/__tests__/assistant-tools-master-data-calculation-rules-read.test.ts
@@ -0,0 +1,75 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { countPlanningEntries } from "@capakraken/application";
+import { SystemRole } from "@capakraken/shared";
+
+vi.mock("@capakraken/application", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@capakraken/application")>();
+  return {
+    ...actual,
+    countPlanningEntries: vi.fn().mockResolvedValue({ countsByRoleId: new Map() }),
+    getDashboardBudgetForecast: vi.fn().mockResolvedValue([]),
+    getDashboardPeakTimes: vi.fn().mockResolvedValue([]),
+    listAssignmentBookings: vi.fn().mockResolvedValue([]),
+  };
+});
+
+import { executeTool } from "../router/assistant-tools.js";
+import { createToolContext } from "./assistant-tools-master-data-read-test-helpers.js";
+
+describe("assistant master data calculation rule read tools", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    vi.mocked(countPlanningEntries).mockResolvedValue({ countsByRoleId: new Map() });
+  });
+
+  it("routes calculation rule reads through their backing router", async () => {
+    const db = {
+      calculationRule: {
+        findMany: vi.fn().mockResolvedValue([
+          {
+            id: "calc_1",
+            name: "Rush Fee",
+            description: "Adds cost for rush work",
+            isActive: true,
+            triggerType: "RUSH",
+            orderType: null,
+            costEffect: "INCREASE",
+            costReductionPercent: null,
+            chargeabilityEffect: "NONE",
+            priority: 90,
+            project: { id: "proj_1", name: "Falcon", shortCode: "FAL" },
+          },
+        ]),
+      },
+    };
+    const ctx = createToolContext(db, { userRole: SystemRole.CONTROLLER });
+
+    const calculationRulesResult = await executeTool("list_calculation_rules", "{}", ctx);
+
+    expect(db.calculationRule.findMany).toHaveBeenCalledWith({
+      orderBy: [{ priority: "desc" }, { name: "asc" }],
+      include: {
+        project: {
+          select: {
+            id: true,
+            shortCode: true,
+            name: true,
+            status: true,
+            endDate: true,
+          },
+        },
+      },
+    });
+
+    expect(JSON.parse(calculationRulesResult.content)).toEqual([
+      expect.objectContaining({
+        id: "calc_1",
+        name: "Rush Fee",
+        project: expect.objectContaining({
+          id: "proj_1",
+          shortCode: "FAL",
+        }),
+      }),
+    ]);
+  });
+});
diff --git a/packages/api/src/__tests__/assistant-tools-master-data-clients-read.test.ts b/packages/api/src/__tests__/assistant-tools-master-data-clients-read.test.ts
new file mode 100644
index 0000000..586cf79
--- /dev/null
+++ b/packages/api/src/__tests__/assistant-tools-master-data-clients-read.test.ts
@@ -0,0 +1,75 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { PermissionKey, SystemRole } from "@capakraken/shared";
+
+vi.mock("@capakraken/application", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@capakraken/application")>();
+  return {
+    ...actual,
+    countPlanningEntries: vi.fn().mockResolvedValue({ countsByRoleId: new Map() }),
+    getDashboardBudgetForecast: vi.fn().mockResolvedValue([]),
+    getDashboardPeakTimes: vi.fn().mockResolvedValue([]),
+    listAssignmentBookings: vi.fn().mockResolvedValue([]),
+  };
+});
+
+import { countPlanningEntries } from "@capakraken/application";
+import { executeTool } from "../router/assistant-tools.js";
+import { createToolContext } from "./assistant-tools-master-data-read-test-helpers.js";
+
+describe("assistant master data clients read tool", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    vi.mocked(countPlanningEntries).mockResolvedValue({ countsByRoleId: new Map() });
+  });
+
+  it("routes client reads through their backing router", async () => {
+    const db = {
+      client: {
+        findMany: vi.fn().mockResolvedValue([
+          {
+            id: "client_1",
+            name: "Acme Mobility",
+            code: "ACM",
+            parentId: null,
+            isActive: true,
+            sortOrder: 1,
+            tags: [],
+            createdAt: new Date("2026-01-01T00:00:00.000Z"),
+            updatedAt: new Date("2026-01-02T00:00:00.000Z"),
+            _count: { children: 0, projects: 4 },
+          },
+        ]),
+      },
+    };
+    const ctx = createToolContext(db, {
+      userRole: SystemRole.CONTROLLER,
+      permissions: [PermissionKey.VIEW_PLANNING],
+    });
+
+    const clientsResult = await executeTool(
+      "list_clients",
+      JSON.stringify({ query: "ACM", limit: 5 }),
+      ctx,
+    );
+
+    expect(db.client.findMany).toHaveBeenCalledWith({
+      where: {
+        isActive: true,
+        OR: [
+          { name: { contains: "ACM", mode: "insensitive" } },
+          { code: { contains: "ACM", mode: "insensitive" } },
+        ],
+      },
+      include: { _count: { select: { children: true, projects: true } } },
+      orderBy: [{ sortOrder: "asc" }, { name: "asc" }],
+    });
+    expect(JSON.parse(clientsResult.content)).toEqual([
+      {
+        id: "client_1",
+        name: "Acme Mobility",
+        code: "ACM",
+        projectCount: 4,
+      },
+    ]);
+  });
+});
diff --git a/packages/api/src/__tests__/assistant-tools-master-data-effort-experience-read.test.ts b/packages/api/src/__tests__/assistant-tools-master-data-effort-experience-read.test.ts
new file mode 100644
index 0000000..b7a62b9
--- /dev/null
+++ b/packages/api/src/__tests__/assistant-tools-master-data-effort-experience-read.test.ts
@@ -0,0 +1,119 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { countPlanningEntries } from "@capakraken/application";
+import { SystemRole } from "@capakraken/shared";
+
+vi.mock("@capakraken/application", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@capakraken/application")>();
+  return {
+    ...actual,
+    countPlanningEntries: vi.fn().mockResolvedValue({ countsByRoleId: new Map() }),
+    getDashboardBudgetForecast: vi.fn().mockResolvedValue([]),
+    getDashboardPeakTimes: vi.fn().mockResolvedValue([]),
+    listAssignmentBookings: vi.fn().mockResolvedValue([]),
+  };
+});
+
+import { executeTool } from "../router/assistant-tools.js";
+import { createToolContext } from "./assistant-tools-master-data-read-test-helpers.js";
+
+describe("assistant master data effort and experience read tools", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    vi.mocked(countPlanningEntries).mockResolvedValue({ countsByRoleId: new Map() });
+  });
+
+  it("routes effort rule and experience multiplier reads through their backing routers", async () => {
+    const db = {
+      effortRuleSet: {
+        findMany: vi.fn().mockResolvedValue([
+          {
+            id: "ers_default",
+            name: "Default Effort",
+            isDefault: true,
+            rules: [
+              {
+                id: "eff_1",
+                description: "Animation per shot",
+                scopeType: "SHOT",
+                discipline: "Animation",
+                chapter: "3D",
+                unitMode: "per_item",
+                hoursPerUnit: 12,
+                sortOrder: 0,
+              },
+            ],
+          },
+        ]),
+      },
+      experienceMultiplierSet: {
+        findMany: vi.fn().mockResolvedValue([
+          {
+            id: "ems_default",
+            name: "Default Multipliers",
+            isDefault: true,
+            rules: [
+              {
+                id: "exp_1",
+                description: "Senior DE uplift",
+                chapter: "3D",
+                location: "DE",
+                level: "Senior",
+                costMultiplier: 1.2,
+                billMultiplier: 1.15,
+                shoringRatio: 0.4,
+                additionalEffortRatio: 0.1,
+                sortOrder: 0,
+              },
+            ],
+          },
+        ]),
+      },
+    };
+    const ctx = createToolContext(db, { userRole: SystemRole.CONTROLLER });
+
+    const effortRulesResult = await executeTool("list_effort_rules", "{}", ctx);
+    const experienceMultipliersResult = await executeTool("list_experience_multipliers", "{}", ctx);
+
+    expect(db.effortRuleSet.findMany).toHaveBeenCalledWith({
+      include: {
+        rules: { orderBy: { sortOrder: "asc" } },
+      },
+      orderBy: [{ isDefault: "desc" }, { name: "asc" }],
+    });
+    expect(db.experienceMultiplierSet.findMany).toHaveBeenCalledWith({
+      include: {
+        rules: { orderBy: { sortOrder: "asc" } },
+      },
+      orderBy: [{ isDefault: "desc" }, { name: "asc" }],
+    });
+
+    expect(JSON.parse(effortRulesResult.content)).toEqual([
+      {
+        id: "eff_1",
+        description: "Animation per shot",
+        scopeType: "SHOT",
+        discipline: "Animation",
+        chapter: "3D",
+        unitMode: "per_item",
+        hoursPerUnit: 12,
+        sortOrder: 0,
+        ruleSet: { name: "Default Effort", isDefault: true },
+      },
+    ]);
+    expect(JSON.parse(experienceMultipliersResult.content)).toEqual([
+      {
+        id: "exp_1",
+        description: "Senior DE uplift",
+        chapter: "3D",
+        location: "DE",
+        level: "Senior",
+        costMultiplier: 1.2,
+        billMultiplier: 1.15,
+        shoringRatio: 0.4,
+        additionalEffortRatio: 0.1,
+        sortOrder: 0,
+        multiplierSet: { name: "Default Multipliers", isDefault: true },
+      },
+    ]);
+  });
+});
diff --git a/packages/api/src/__tests__/assistant-tools-master-data-management-utilization-read.test.ts b/packages/api/src/__tests__/assistant-tools-master-data-management-utilization-read.test.ts
new file mode 100644
index 0000000..547b027
--- /dev/null
+++ b/packages/api/src/__tests__/assistant-tools-master-data-management-utilization-read.test.ts
@@ -0,0 +1,98 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { countPlanningEntries } from "@capakraken/application";
+import { PermissionKey, SystemRole } from "@capakraken/shared";
+
+vi.mock("@capakraken/application", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@capakraken/application")>();
+  return {
+    ...actual,
+    countPlanningEntries: vi.fn().mockResolvedValue({ countsByRoleId: new Map() }),
+    getDashboardBudgetForecast: vi.fn().mockResolvedValue([]),
+    getDashboardPeakTimes: vi.fn().mockResolvedValue([]),
+    listAssignmentBookings: vi.fn().mockResolvedValue([]),
+  };
+});
+
+import { executeTool } from "../router/assistant-tools.js";
+import { createToolContext } from "./assistant-tools-master-data-read-test-helpers.js";
+
+describe("assistant master data management and utilization read tools", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    vi.mocked(countPlanningEntries).mockResolvedValue({ countsByRoleId: new Map() });
+  });
+
+  it("routes management level and utilization category reads through their backing routers", async () => {
+    const db = {
+      managementLevelGroup: {
+        findMany: vi.fn().mockResolvedValue([
+          {
+            id: "mlg_exec",
+            name: "Executive",
+            targetPercentage: 75,
+            levels: [{ id: "ml_partner", name: "Partner" }],
+          },
+        ]),
+      },
+      utilizationCategory: {
+        findMany: vi.fn().mockResolvedValue([
+          {
+            id: "util_billable",
+            code: "BILLABLE",
+            name: "Billable",
+            description: "Client work",
+            isActive: true,
+            sortOrder: 1,
+          },
+        ]),
+        findUnique: vi.fn().mockResolvedValue({
+          id: "util_billable",
+          code: "BILLABLE",
+          name: "Billable",
+          description: "Client work",
+          isActive: true,
+          sortOrder: 1,
+          _count: { projects: 3 },
+        }),
+      },
+    };
+    const ctx = createToolContext(db, {
+      userRole: SystemRole.CONTROLLER,
+      permissions: [PermissionKey.VIEW_PLANNING],
+    });
+
+    const managementLevelsResult = await executeTool("list_management_levels", "{}", ctx);
+    const utilizationCategoriesResult = await executeTool("list_utilization_categories", "{}", ctx);
+
+    expect(db.managementLevelGroup.findMany).toHaveBeenCalledWith({
+      include: { levels: { orderBy: { name: "asc" } } },
+      orderBy: { sortOrder: "asc" },
+    });
+    expect(db.utilizationCategory.findMany).toHaveBeenCalledWith({
+      where: {},
+      orderBy: { sortOrder: "asc" },
+    });
+    expect(db.utilizationCategory.findUnique).toHaveBeenCalledWith({
+      where: { id: "util_billable" },
+      include: { _count: { select: { projects: true } } },
+    });
+
+    expect(JSON.parse(managementLevelsResult.content)).toEqual([
+      {
+        id: "mlg_exec",
+        name: "Executive",
+        target: "75%",
+        levels: [{ id: "ml_partner", name: "Partner" }],
+      },
+    ]);
+    expect(JSON.parse(utilizationCategoriesResult.content)).toEqual([
+      {
+        id: "util_billable",
+        code: "BILLABLE",
+        name: "Billable",
+        description: "Client work",
+        projectCount: 3,
+      },
+    ]);
+  });
+});
diff --git a/packages/api/src/__tests__/assistant-tools-master-data-org-units-read.test.ts b/packages/api/src/__tests__/assistant-tools-master-data-org-units-read.test.ts
new file mode 100644
index 0000000..cb896ea
--- /dev/null
+++ b/packages/api/src/__tests__/assistant-tools-master-data-org-units-read.test.ts
@@ -0,0 +1,95 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { PermissionKey, SystemRole } from "@capakraken/shared";
+
+vi.mock("@capakraken/application", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@capakraken/application")>();
+  return {
+    ...actual,
+    countPlanningEntries: vi.fn().mockResolvedValue({ countsByRoleId: new Map() }),
+    getDashboardBudgetForecast: vi.fn().mockResolvedValue([]),
+    getDashboardPeakTimes: vi.fn().mockResolvedValue([]),
+    listAssignmentBookings: vi.fn().mockResolvedValue([]),
+  };
+});
+
+import { countPlanningEntries } from "@capakraken/application";
+import { executeTool } from "../router/assistant-tools.js";
+import { createToolContext } from "./assistant-tools-master-data-read-test-helpers.js";
+
+describe("assistant master data org units read tool", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    vi.mocked(countPlanningEntries).mockResolvedValue({ countsByRoleId: new Map() });
+  });
+
+  it("routes org unit reads through their backing router", async () => {
+    const db = {
+      orgUnit: {
+        findMany: vi.fn().mockResolvedValue([
+          {
+            id: "ou_delivery",
+            name: "Delivery",
+            shortName: "DEL",
+            level: 5,
+            parentId: null,
+            sortOrder: 1,
+            isActive: true,
+            createdAt: new Date("2026-01-01T00:00:00.000Z"),
+            updatedAt: new Date("2026-01-02T00:00:00.000Z"),
+          },
+        ]),
+        findUnique: vi.fn().mockResolvedValue({
+          id: "ou_delivery",
+          name: "Delivery",
+          shortName: "DEL",
+          level: 5,
+          parentId: null,
+          sortOrder: 1,
+          isActive: true,
+          createdAt: new Date("2026-01-01T00:00:00.000Z"),
+          updatedAt: new Date("2026-01-02T00:00:00.000Z"),
+          parent: null,
+          children: [],
+          _count: { resources: 7 },
+        }),
+      },
+    };
+    const ctx = createToolContext(db, {
+      userRole: SystemRole.CONTROLLER,
+      permissions: [PermissionKey.VIEW_ALL_RESOURCES],
+    });
+
+    const orgUnitsResult = await executeTool(
+      "list_org_units",
+      JSON.stringify({ level: 5 }),
+      ctx,
+    );
+
+    expect(db.orgUnit.findMany).toHaveBeenCalledWith({
+      where: {
+        level: 5,
+        isActive: true,
+      },
+      orderBy: [{ level: "asc" }, { sortOrder: "asc" }, { name: "asc" }],
+    });
+    expect(db.orgUnit.findUnique).toHaveBeenCalledWith({
+      where: { id: "ou_delivery" },
+      include: {
+        parent: true,
+        children: { orderBy: { sortOrder: "asc" } },
+        _count: { select: { resources: true } },
+      },
+    });
+
+    expect(JSON.parse(orgUnitsResult.content)).toEqual([
+      {
+        id: "ou_delivery",
+        name: "Delivery",
+        shortName: "DEL",
+        level: 5,
+        parent: null,
+        resourceCount: 7,
+      },
+    ]);
+  });
+});
diff --git a/packages/api/src/__tests__/assistant-tools-master-data-read-test-helpers.ts b/packages/api/src/__tests__/assistant-tools-master-data-read-test-helpers.ts
new file mode 100644
index 0000000..dceafe0
--- /dev/null
+++ b/packages/api/src/__tests__/assistant-tools-master-data-read-test-helpers.ts
@@ -0,0 +1,29 @@
+import { PermissionKey, SystemRole } from "@capakraken/shared";
+
+import type { ToolContext } from "../router/assistant-tools.js";
+
+export function createToolContext(
+  db: Record<string, unknown>,
+  options?: {
+    permissions?: PermissionKey[];
+    userRole?: SystemRole;
+  },
+): ToolContext {
+  const userRole = options?.userRole ?? SystemRole.ADMIN;
+  return {
+    db: db as ToolContext["db"],
+    userId: "user_1",
+    userRole,
+    permissions: new Set(options?.permissions ?? []),
+    session: {
+      user: { email: "assistant@example.com", name: "Assistant User", image: null },
+      expires: "2026-03-29T00:00:00.000Z",
+    },
+    dbUser: {
+      id: "user_1",
+      systemRole: userRole,
+      permissionOverrides: null,
+    },
+    roleDefaults: null,
+  };
+}