diff --git a/src/features/housekeeping/foundation/commands/dispatcher.test.ts b/src/features/housekeeping/foundation/commands/dispatcher.test.ts
index a484a377bb..eeb5130b99 100644
--- a/src/features/housekeeping/foundation/commands/dispatcher.test.ts
+++ b/src/features/housekeeping/foundation/commands/dispatcher.test.ts
@@ -5,6 +5,7 @@ import type { HousekeepingCapabilityContext } from "../contracts";
 import { anyCapability, fail, ok } from "../contracts";
 import { dispatchHousekeepingCommand } from "./dispatcher";
 import {
+	getHousekeepingCommand,
 	type HousekeepingCommand,
 	registerHousekeepingCommand,
 } from "./registry";
@@ -150,6 +151,129 @@ describe("dispatchHousekeepingCommand", () => {
 		expect(executed).toBe(false);
 	});
 
+	it("uses unchanged private validation after public descriptor mutation attempts", async () => {
+		const commandId = "system.dispatch.reflective-schema-mutation";
+		let executions = 0;
+		register(
+			baseCommand(commandId, {
+				input: z.object({
+					objectDescriptor: z.string().min(3),
+					objectDescriptors: z.string().min(3),
+					reflectDescriptor: z.string().min(3),
+				}),
+				execute: async (context) => {
+					executions += 1;
+					return ok(null, context.correlationId);
+				},
+			}),
+		);
+		const registered = getHousekeepingCommand(commandId);
+		if (!registered) throw new Error("registered command missing");
+
+		const readers = [
+			["objectDescriptor", Object.getOwnPropertyDescriptor],
+			[
+				"objectDescriptors",
+				(target: object, property: PropertyKey) =>
+					Reflect.get(Object.getOwnPropertyDescriptors(target), property) as
+						| PropertyDescriptor
+						| undefined,
+			],
+			["reflectDescriptor", Reflect.getOwnPropertyDescriptor],
+		] as const;
+		const descriptorValue = (
+			target: object,
+			property: PropertyKey,
+			readDescriptor: (
+				target: object,
+				property: PropertyKey,
+			) => PropertyDescriptor | undefined,
+		): unknown => {
+			const descriptor = readDescriptor(target, property);
+			if (!descriptor) {
+				throw new Error(`missing descriptor: ${String(property)}`);
+			}
+			if ("value" in descriptor) return descriptor.value;
+			if (descriptor.get) return Reflect.apply(descriptor.get, target, []);
+			return undefined;
+		};
+
+		for (const [field, readDescriptor] of readers) {
+			const definition = descriptorValue(
+				registered.input,
+				"def",
+				readDescriptor,
+			) as object;
+			const shape = descriptorValue(
+				definition,
+				"shape",
+				readDescriptor,
+			) as Record<string, z.ZodType>;
+			const child = shape[field];
+			if (!child) throw new Error(`public child missing: ${field}`);
+			const childDefinition = descriptorValue(
+				child,
+				"def",
+				readDescriptor,
+			) as object;
+			const checks = descriptorValue(
+				childDefinition,
+				"checks",
+				readDescriptor,
+			) as readonly object[];
+			const internal = descriptorValue(
+				checks[0] as object,
+				"_zod",
+				readDescriptor,
+			) as object;
+			const checkDefinition = descriptorValue(
+				internal,
+				"def",
+				readDescriptor,
+			) as { minimum: number };
+			try {
+				shape[field] = z.number();
+			} catch {
+				// A readonly facade may reject the assignment.
+			}
+			try {
+				checkDefinition.minimum = 0;
+			} catch {
+				// A readonly facade may reject the assignment.
+			}
+		}
+
+		const forged = await dispatchHousekeepingCommand(
+			{
+				commandId,
+				input: {
+					objectDescriptor: 7,
+					objectDescriptors: 7,
+					reflectDescriptor: 7,
+				},
+			},
+			dependencies(),
+		);
+		expect(forged).toMatchObject({
+			ok: false,
+			error: { code: "VALIDATION" },
+		});
+		expect(executions).toBe(0);
+
+		const valid = await dispatchHousekeepingCommand(
+			{
+				commandId,
+				input: {
+					objectDescriptor: "valid",
+					objectDescriptors: "valid",
+					reflectDescriptor: "valid",
+				},
+			},
+			dependencies(),
+		);
+		expect(valid).toMatchObject({ ok: true });
+		expect(executions).toBe(1);
+	});
 	it("rejects a missing required reason before the command can execute", async () => {
 		let executed = false;
 		const audit = auditRecorder();
diff --git a/src/features/housekeeping/foundation/commands/registry.test.ts b/src/features/housekeeping/foundation/commands/registry.test.ts
index f38d721d59..39498895b2 100644
--- a/src/features/housekeeping/foundation/commands/registry.test.ts
+++ b/src/features/housekeeping/foundation/commands/registry.test.ts
@@ -25,6 +25,52 @@ function command(
 	};
 }
 
+type DescriptorReader = (
+	target: object,
+	property: PropertyKey,
+) => PropertyDescriptor | undefined;
+
+const descriptorReaders = [
+	[
+		"Object.getOwnPropertyDescriptor",
+		"object-descriptor",
+		Object.getOwnPropertyDescriptor,
+	],
+	[
+		"Object.getOwnPropertyDescriptors",
+		"object-descriptors",
+		(target: object, property: PropertyKey) =>
+			Reflect.get(Object.getOwnPropertyDescriptors(target), property) as
+				| PropertyDescriptor
+				| undefined,
+	],
+	[
+		"Reflect.getOwnPropertyDescriptor",
+		"reflect-descriptor",
+		Reflect.getOwnPropertyDescriptor,
+	],
+] as const satisfies readonly (readonly [string, string, DescriptorReader])[];
+
+function readDescriptorValue(
+	target: object,
+	property: PropertyKey,
+	readDescriptor: DescriptorReader,
+): unknown {
+	const descriptor = readDescriptor(target, property);
+	if (!descriptor) throw new Error(`missing descriptor: ${String(property)}`);
+	if ("value" in descriptor) return descriptor.value;
+	if (descriptor.get) return Reflect.apply(descriptor.get, target, []);
+	return undefined;
+}
+
+function attemptMutation(mutate: () => void): void {
+	try {
+		mutate();
+	} catch {
+		// Readonly public views may reject the mutation directly.
+	}
+}
+
 describe("housekeeping command registry", () => {
 	it("returns the validated snapshot registered under its global ID", () => {
 		const registered = command("people.registry.lookup");
@@ -296,6 +342,170 @@ describe("housekeeping command registry", () => {
 		});
 		expect(String(thrown)).not.toContain("caller lazy secret");
 	});
+	it.each(descriptorReaders)(
+		"keeps private validation unchanged after nested mutation through %s",
+		(_api, suffix, readDescriptor) => {
+			const input = z.object({ value: z.string().min(3) });
+			const id = `people.registry.${suffix}`;
+			registerHousekeepingCommand({
+				...command(id),
+				input,
+				execute: async (context) => ok({ id: 1 }, context.correlationId),
+			} as HousekeepingCommand<z.output<typeof input>, { id: number }>);
+			const registered = getHousekeepingCommand(id);
+			if (!registered) throw new Error("registered command missing");
+
+			const definition = readDescriptorValue(
+				registered.input,
+				"def",
+				readDescriptor,
+			) as object;
+			const shape = readDescriptorValue(
+				definition,
+				"shape",
+				readDescriptor,
+			) as { value: z.ZodType };
+			const child = shape.value;
+			const childDefinition = readDescriptorValue(
+				child,
+				"def",
+				readDescriptor,
+			) as object;
+			const checks = readDescriptorValue(
+				childDefinition,
+				"checks",
+				readDescriptor,
+			) as readonly object[];
+			const internal = readDescriptorValue(
+				checks[0] as object,
+				"_zod",
+				readDescriptor,
+			) as object;
+			const checkDefinition = readDescriptorValue(
+				internal,
+				"def",
+				readDescriptor,
+			) as { minimum: number };
+
+			attemptMutation(() => {
+				shape.value = z.number();
+			});
+			attemptMutation(() => {
+				checkDefinition.minimum = 0;
+			});
+
+			expect(registered.input.safeParse({ value: "ab" }).success).toBe(false);
+			expect(registered.input.safeParse({ value: "abcd" }).success).toBe(true);
+			expect(registered.input.safeParse({ value: 7 }).success).toBe(false);
+		},
+	);
+
+	it("keeps own-key and symbol iteration detached from private checks", () => {
+		const input = z.object({ value: z.string().min(3) });
+		const id = "people.registry.symbol-iteration";
+		registerHousekeepingCommand({
+			...command(id),
+			input,
+			execute: async (context) => ok({ id: 1 }, context.correlationId),
+		} as HousekeepingCommand<z.output<typeof input>, { id: number }>);
+		const registered = getHousekeepingCommand(id);
+		if (!registered) throw new Error("registered command missing");
+
+		const publicInput = registered.input as z.ZodObject<{
+			value: z.ZodString;
+		}>;
+		const shape = publicInput.shape;
+		expect(Reflect.ownKeys(publicInput.def)).toContain("shape");
+		expect(Object.keys(shape)).toEqual(["value"]);
+		const child = Object.entries(shape)[0]?.[1];
+		if (!child) throw new Error("public child schema missing");
+		const checks = child.def.checks ?? [];
+		const spreadChecks = [...checks];
+		const iterator = checks[Symbol.iterator]();
+		const iteratedCheck = iterator.next().value;
+		if (!iteratedCheck) throw new Error("public check missing");
+		expect(spreadChecks[0]).toBe(iteratedCheck);
+
+		attemptMutation(() => {
+			(
+				iteratedCheck as unknown as {
+					_zod: { def: { minimum: number } };
+				}
+			)._zod.def.minimum = 0;
+		});
+
+		expect(registered.input.safeParse({ value: "ab" }).success).toBe(false);
+		expect(registered.input.safeParse({ value: "abcd" }).success).toBe(true);
+	});
+
+	it("keeps prototype methods operational without passing the private schema to callbacks", async () => {
+		const input = z.object({ value: z.string().min(3) });
+		const id = "people.registry.prototype-methods";
+		registerHousekeepingCommand({
+			...command(id),
+			input,
+			execute: async (context) => ok({ id: 1 }, context.correlationId),
+		} as HousekeepingCommand<z.output<typeof input>, { id: number }>);
+		const registered = getHousekeepingCommand(id);
+		if (!registered) throw new Error("registered command missing");
+		const publicInput = registered.input as z.ZodObject<{
+			value: z.ZodString;
+		}>;
+
+		const publicPrototype = Object.getPrototypeOf(publicInput);
+		expect(publicPrototype).toBe(Reflect.getPrototypeOf(publicInput));
+		const prototypeMutation = Symbol("prototype-mutation");
+		Object.defineProperty(publicPrototype, prototypeMutation, {
+			configurable: true,
+			value(this: z.ZodObject<{ value: z.ZodString }>): unknown {
+				attemptMutation(() => {
+					this.def.shape.value = z.number() as never;
+				});
+				return this.def;
+			},
+		});
+		try {
+			(
+				publicInput as typeof publicInput & {
+					[prototypeMutation](): unknown;
+				}
+			)[prototypeMutation]();
+		} finally {
+			Reflect.deleteProperty(publicPrototype, prototypeMutation);
+		}
+		expect(publicInput.safeParse({ value: "abcd" }).success).toBe(true);
+		expect(publicInput.safeParse({ value: 7 }).success).toBe(false);
+
+		let appliedSchema: z.ZodType | undefined;
+		const applied = publicInput.apply((schema) => {
+			appliedSchema = schema;
+			return schema;
+		});
+		expect(appliedSchema).toBe(publicInput);
+		expect(applied).toBe(publicInput);
+
+		let externallyRegistered: z.ZodType | undefined;
+		const externalRegistry = {
+			add(schema: z.ZodType): void {
+				externallyRegistered = schema;
+			},
+		};
+		expect(
+			publicInput.register(externalRegistry as never, undefined as never),
+		).toBe(publicInput);
+		expect(externallyRegistered).toBe(publicInput);
+
+		const partial = publicInput.partial();
+		const picked = publicInput.pick({ value: true });
+		expect(partial.safeParse({}).success).toBe(true);
+		expect(picked.safeParse({ value: "abcd" }).success).toBe(true);
+		expect((await publicInput.safeParseAsync({ value: "ab" })).success).toBe(
+			false,
+		);
+		expect((await publicInput.safeParseAsync({ value: "abcd" })).success).toBe(
+			true,
+		);
+	});
 	it("seals the global registry after deterministic bootstrap", () => {
 		sealHousekeepingCommandRegistry();
 
diff --git a/src/features/housekeeping/foundation/commands/registry.ts b/src/features/housekeeping/foundation/commands/registry.ts
index 288a68e770..9b38d65440 100644
--- a/src/features/housekeeping/foundation/commands/registry.ts
+++ b/src/features/housekeeping/foundation/commands/registry.ts
@@ -357,6 +357,22 @@ function isZodInternalNode(value: object): value is ZodInternalNode {
 
 function createReadonlyValidationFacade<T extends z.ZodType>(schema: T): T {
 	const views = new WeakMap<object, unknown>();
+	const parseResultMethods = new Set<PropertyKey>([
+		"parse",
+		"safeParse",
+		"parseAsync",
+		"safeParseAsync",
+		"spa",
+		"encode",
+		"decode",
+		"encodeAsync",
+		"decodeAsync",
+		"safeEncode",
+		"safeDecode",
+		"safeEncodeAsync",
+		"safeDecodeAsync",
+		"toJSONSchema",
+	]);
 
 	function readonlyView(value: unknown): unknown {
 		if (
@@ -369,56 +385,208 @@ function createReadonlyValidationFacade<T extends z.ZodType>(schema: T): T {
 		if (cached !== undefined) return cached;
 		if (value instanceof z.ZodType) return schemaFacade(value);
 		if (typeof value === "function") {
-			const wrapped = (...args: unknown[]) =>
-				readonlyView(Reflect.apply(value, undefined, args));
-			views.set(value, wrapped);
-			return Object.freeze(wrapped);
+			return functionFacade(value as (...args: never[]) => unknown);
 		}
-
-		const view = new Proxy(value, {
-			defineProperty: () => false,
-			deleteProperty: () => false,
-			get: (target, property, receiver) => {
-				const raw = Reflect.get(target, property, receiver);
-				if (typeof raw !== "function") return readonlyView(raw);
-				return (...args: unknown[]) =>
-					readonlyView(Reflect.apply(raw, receiver, args));
-			},
-			set: () => false,
-			setPrototypeOf: () => false,
-		});
-		views.set(value, view);
-		return view;
+		if (Array.isArray(value)) return arrayFacade(value);
+		if (value instanceof Map) return mapFacade(value);
+		if (value instanceof Set) return setFacade(value);
+		if (value instanceof RegExp) {
+			const detached = new RegExp(value.source, value.flags);
+			views.set(value, detached);
+			return Object.freeze(detached);
+		}
+		if (value instanceof Date) {
+			const detached = new Date(value.getTime());
+			views.set(value, detached);
+			return Object.freeze(detached);
+		}
+		return objectFacade(value);
 	}
 
+	function functionFacade(value: (...args: never[]) => unknown): unknown {
+		const wrapped = function (this: unknown, ...args: unknown[]) {
+			const result = new.target
+				? Reflect.construct(value, args)
+				: Reflect.apply(value, this, args);
+			return readonlyView(result);
+		};
+		views.set(value, wrapped);
+		return Object.freeze(wrapped);
+	}
+
+	function arrayFacade(value: readonly unknown[]): readonly unknown[] {
+		const detached: unknown[] = [];
+		views.set(value, detached);
+		for (const item of value) detached.push(readonlyView(item));
+		return Object.freeze(detached);
+	}
+
+	function mapFacade(
+		value: ReadonlyMap<unknown, unknown>,
+	): ReadonlyMap<unknown, unknown> {
+		const detached = new Map<unknown, unknown>();
+		views.set(value, detached);
+		for (const [key, item] of value) {
+			detached.set(readonlyView(key), readonlyView(item));
+		}
+		return Object.freeze(detached);
+	}
+
+	function setFacade(value: ReadonlySet<unknown>): ReadonlySet<unknown> {
+		const detached = new Set<unknown>();
+		views.set(value, detached);
+		for (const item of value) detached.add(readonlyView(item));
+		return Object.freeze(detached);
+	}
+
+	function objectFacade(value: object): object {
+		const detached = Object.create(Object.getPrototypeOf(value)) as Record<
+			PropertyKey,
+			unknown
+		>;
+		views.set(value, detached);
+		copyReadonlyProperties(value, detached, (method) =>
+			boundFunctionFacade(method, value),
+		);
+		return Object.freeze(detached);
+	}
+
+	function boundFunctionFacade(
+		method: (...args: never[]) => unknown,
+		receiver: object,
+	): (...args: unknown[]) => unknown {
+		return Object.freeze((...args: unknown[]) =>
+			readonlyView(Reflect.apply(method, receiver, args)),
+		);
+	}
+
+	function copyReadonlyProperties(
+		source: object,
+		destination: Record<PropertyKey, unknown>,
+		wrapMethod: (
+			method: (...args: never[]) => unknown,
+			property: PropertyKey,
+		) => unknown,
+	): void {
+		for (const key of Reflect.ownKeys(source)) {
+			const descriptor = Object.getOwnPropertyDescriptor(source, key);
+			if (!descriptor) continue;
+			if ("value" in descriptor) {
+				Object.defineProperty(destination, key, {
+					configurable: false,
+					enumerable: descriptor.enumerable,
+					value:
+						typeof descriptor.value === "function"
+							? wrapMethod(descriptor.value, key)
+							: readonlyView(descriptor.value),
+					writable: false,
+				});
+				continue;
+			}
+
+			const getter = descriptor.get;
+			const safeGetter = getter
+				? () => readonlyView(Reflect.apply(getter, source, []))
+				: undefined;
+			Object.defineProperty(destination, key, {
+				configurable: false,
+				enumerable: descriptor.enumerable,
+				get: safeGetter,
+			});
+		}
+	}
+
+	function materializeSchemaPrototypeMethods(target: z.ZodType): void {
+		let prototype = Object.getPrototypeOf(target);
+		while (prototype && prototype !== Object.prototype) {
+			for (const property of Reflect.ownKeys(prototype)) {
+				if (Object.hasOwn(target, property)) continue;
+				const descriptor = Object.getOwnPropertyDescriptor(prototype, property);
+				if (
+					!descriptor?.get ||
+					!descriptor.set ||
+					!descriptor.configurable ||
+					descriptor.enumerable
+				) {
+					continue;
+				}
+				Reflect.get(target, property, target);
+			}
+			prototype = Object.getPrototypeOf(prototype);
+		}
+	}
 	function schemaFacade<S extends z.ZodType>(target: S): S {
 		const cached = views.get(target);
 		if (cached !== undefined) return cached as S;
 
-		const facade = Object.create(Object.getPrototypeOf(target)) as Record<
+		materializeSchemaPrototypeMethods(target);
+		const shell = Object.create(Object.getPrototypeOf(target)) as Record<
 			PropertyKey,
 			unknown
 		>;
+		let facade: S;
+		facade = new Proxy(shell, {
+			defineProperty: () => false,
+			deleteProperty: () => false,
+			get: (publicShell, property, receiver) => {
+				if (Object.hasOwn(publicShell, property)) {
+					return Reflect.get(publicShell, property, receiver);
+				}
+				const inherited = Reflect.get(publicShell, property, receiver);
+				return readonlyView(inherited);
+			},
+			set: () => false,
+			setPrototypeOf: () => false,
+		}) as unknown as S;
 		views.set(target, facade);
-		for (const key of Reflect.ownKeys(target)) {
-			const raw = Reflect.get(target, key);
-			const exposed =
-				typeof raw === "function"
-					? (...args: unknown[]) => {
-							const result = Reflect.apply(raw, target, args);
-							return result instanceof z.ZodType
-								? isolateValidationGraph(result, "derived-schema")
-								: result;
-						}
-					: readonlyView(raw);
-			Object.defineProperty(facade, key, {
-				configurable: false,
-				enumerable: Object.prototype.propertyIsEnumerable.call(target, key),
-				value: exposed,
-				writable: false,
+		copyReadonlyProperties(target, shell, (method, property) =>
+			schemaMethodFacade(method, property, target, facade),
+		);
+		Object.freeze(shell);
+		return facade;
+	}
+
+	function schemaMethodFacade<S extends z.ZodType>(
+		method: (...args: never[]) => unknown,
+		property: PropertyKey,
+		target: S,
+		facade: S,
+	): (...args: unknown[]) => unknown {
+		if (property === "apply") {
+			return Object.freeze((...args: unknown[]) => {
+				const callback = args[0];
+				if (typeof callback !== "function") {
+					throw new TypeError("schema apply callback missing");
+				}
+				return Reflect.apply(callback, undefined, [facade]);
 			});
 		}
-		return Object.freeze(facade) as S;
+		if (property === "register") {
+			return Object.freeze((...args: unknown[]) => {
+				const registry = args[0];
+				if (
+					typeof registry !== "object" ||
+					registry === null ||
+					typeof (registry as { add?: unknown }).add !== "function"
+				) {
+					throw new TypeError("schema registry missing");
+				}
+				(
+					registry as {
+						add(schema: S, metadata?: unknown): unknown;
+					}
+				).add(facade, args[1]);
+				return facade;
+			});
+		}
+
+		return Object.freeze((...args: unknown[]) => {
+			const result = Reflect.apply(method, target, args);
+			if (result instanceof z.ZodType) {
+				return isolateValidationGraph(result, "derived-schema");
+			}
+			return parseResultMethods.has(property) ? result : readonlyView(result);
+		});
 	}
 
 	return schemaFacade(schema);