diff --git a/tools/ruview-mcp/src/schemas/common.ts b/tools/ruview-mcp/src/schemas/common.ts
new file mode 100644
index 00000000..91b65551
--- /dev/null
+++ b/tools/ruview-mcp/src/schemas/common.ts
@@ -0,0 +1,79 @@
+/**
+ * Shared Zod sub-schemas reused across the ADR-124 §4.1 tool catalog.
+ *
+ * All constraints are sourced from the ADR-124 decision record; comments cite
+ * the specific table row or section that defines the constraint.
+ */
+
+import { z } from "zod";
+
+// ── Shared primitives ──────────────────────────────────────────────────────
+
+/**
+ * Optional node_id — present on almost every tool. Defaults to the single
+ * active node when only one is registered; required for multi-node fleets.
+ */
+export const NodeIdSchema = z
+  .string()
+  .min(1)
+  .optional()
+  .describe("Target node id. Omit to use the single active node.");
+
+/**
+ * Subscription duration in seconds. ADR-124 policy layer caps this at the
+ * value returned by ruview.policy.can_subscribe.max_duration_s; the schema
+ * enforces a hard ceiling of 3600 s (1 h) as a first-line guard.
+ */
+export const DurationSSchema = z
+  .number()
+  .positive()
+  .max(3600)
+  .describe("Subscription duration in seconds (max 3600).");
+
+/**
+ * Optional window in seconds for vitals averaging. Positive, max 300 s.
+ * ADR-124 §4.1 rows vitals.get_breathing / vitals.get_heart_rate.
+ */
+export const WindowSSchema = z
+  .number()
+  .positive()
+  .max(300)
+  .optional()
+  .describe("Averaging window in seconds (max 300).");
+
+/**
+ * The 10 semantic primitive kinds defined in ADR-115 and mirrored in
+ * python/wifi_densepose/client/primitives.py:36-45.
+ */
+export const SemanticPrimitiveKindSchema = z.enum([
+  "presence",
+  "n_persons",
+  "fall_detected",
+  "breathing_rate",
+  "heart_rate",
+  "gesture",
+  "zone_entry",
+  "zone_exit",
+  "movement_intensity",
+  "sleep_quality",
+]);
+
+export type SemanticPrimitiveKind = z.infer<typeof SemanticPrimitiveKindSchema>;
+
+/**
+ * A single 17-keypoint COCO pose result as stored and returned by the
+ * ruvector HNSW index (ADR-016). Used by ruview.vector.store_pose input.
+ */
+export const PosePersonResultSchema = z.object({
+  keypoints: z
+    .array(z.tuple([z.number(), z.number()]))
+    .length(17)
+    .describe("17 COCO keypoints as [x,y] pairs in image-normalised coords."),
+  confidence: z.number().min(0).max(1).describe("Pose confidence score [0,1]."),
+  person_id: z
+    .string()
+    .optional()
+    .describe("AETHER re-ID token, if available."),
+});
+
+export type PosePersonResult = z.infer<typeof PosePersonResultSchema>;
diff --git a/tools/ruview-mcp/src/schemas/index.ts b/tools/ruview-mcp/src/schemas/index.ts
new file mode 100644
index 00000000..8913b41f
--- /dev/null
+++ b/tools/ruview-mcp/src/schemas/index.ts
@@ -0,0 +1,9 @@
+/**
+ * Barrel re-export for @ruvnet/rvagent schema layer.
+ *
+ * Import from this module to get all Zod input schemas, shared sub-schemas,
+ * the TOOL_NAMES catalog, and the TOOL_INPUT_SCHEMAS dispatch map.
+ */
+
+export * from "./common.js";
+export * from "./tools.js";
diff --git a/tools/ruview-mcp/src/schemas/tools.ts b/tools/ruview-mcp/src/schemas/tools.ts
new file mode 100644
index 00000000..0486bc01
--- /dev/null
+++ b/tools/ruview-mcp/src/schemas/tools.ts
@@ -0,0 +1,242 @@
+/**
+ * Zod input schemas for all 20 ADR-124 MCP tools.
+ *
+ * §4.1  — 15 sensing tools (presence, vitals, pose, primitives, bfld, node, vector)
+ * §4.1a — 5 policy / governance tools (RUVIEW-POLICY)
+ *
+ * Each exported schema is named `<CamelCase>InputSchema` matching the tool
+ * name from the ADR-124 §4.1 catalog table. The parallel `TOOL_NAMES` array
+ * is the single source of truth asserted by the schema-coverage test.
+ */
+
+import { z } from "zod";
+import {
+  NodeIdSchema,
+  DurationSSchema,
+  WindowSSchema,
+  SemanticPrimitiveKindSchema,
+  PosePersonResultSchema,
+} from "./common.js";
+
+// ── §4.1 Presence ──────────────────────────────────────────────────────────
+
+/** ruview.presence.now */
+export const PresenceNowInputSchema = z.object({
+  node_id: NodeIdSchema,
+});
+
+// ── §4.1 Vitals ───────────────────────────────────────────────────────────
+
+/** ruview.vitals.get_breathing */
+export const VitalsGetBreathingInputSchema = z.object({
+  node_id: NodeIdSchema,
+  window_s: WindowSSchema,
+});
+
+/** ruview.vitals.get_heart_rate */
+export const VitalsGetHeartRateInputSchema = z.object({
+  node_id: NodeIdSchema,
+  window_s: WindowSSchema,
+});
+
+/** ruview.vitals.get_all */
+export const VitalsGetAllInputSchema = z.object({
+  node_id: NodeIdSchema,
+});
+
+// ── §4.1 Pose ─────────────────────────────────────────────────────────────
+
+/** ruview.pose.latest */
+export const PoseLatestInputSchema = z.object({
+  node_id: NodeIdSchema,
+});
+
+/** ruview.pose.subscribe */
+export const PoseSubscribeInputSchema = z.object({
+  node_id: NodeIdSchema,
+  duration_s: DurationSSchema,
+  callback_url: z
+    .string()
+    .url()
+    .optional()
+    .describe("Webhook URL to receive PoseDataMessage events (optional)."),
+});
+
+// ── §4.1 Primitives ───────────────────────────────────────────────────────
+
+/** ruview.primitives.get */
+export const PrimitivesGetInputSchema = z.object({
+  node_id: NodeIdSchema,
+  primitive: SemanticPrimitiveKindSchema,
+});
+
+/** ruview.primitives.list_active */
+export const PrimitivesListActiveInputSchema = z.object({
+  node_id: NodeIdSchema,
+});
+
+/** ruview.primitives.subscribe */
+export const PrimitivesSubscribeInputSchema = z.object({
+  node_id: NodeIdSchema,
+  primitive: SemanticPrimitiveKindSchema.optional().describe(
+    "Subscribe to a specific primitive. Omit to receive all active primitives."
+  ),
+  duration_s: DurationSSchema,
+});
+
+// ── §4.1 BFLD ────────────────────────────────────────────────────────────
+
+/** ruview.bfld.last_scan */
+export const BfldLastScanInputSchema = z.object({
+  node_id: NodeIdSchema,
+});
+
+/** ruview.bfld.subscribe */
+export const BfldSubscribeInputSchema = z.object({
+  node_id: NodeIdSchema,
+  duration_s: DurationSSchema,
+});
+
+// ── §4.1 Node ────────────────────────────────────────────────────────────
+
+/** ruview.node.list — empty input per ADR-124 §4.1 table */
+export const NodeListInputSchema = z.object({});
+
+/** ruview.node.status */
+export const NodeStatusInputSchema = z.object({
+  node_id: z.string().min(1).describe("Node id to query status for."),
+});
+
+// ── §4.1 Vector ──────────────────────────────────────────────────────────
+
+/** ruview.vector.search_pose */
+export const VectorSearchPoseInputSchema = z.object({
+  query_embedding: z
+    .array(z.number())
+    .min(1)
+    .describe("Dense embedding vector to query against the HNSW index."),
+  k: z
+    .number()
+    .int()
+    .positive()
+    .max(100)
+    .optional()
+    .default(10)
+    .describe("Number of nearest neighbours to return (default 10, max 100)."),
+  node_id: NodeIdSchema,
+});
+
+/** ruview.vector.store_pose */
+export const VectorStorePoseInputSchema = z.object({
+  pose: PosePersonResultSchema,
+  node_id: z.string().min(1).describe("Node id that observed this pose."),
+});
+
+// ── §4.1a Policy / governance tools ──────────────────────────────────────
+
+/** ruview.policy.can_access_vitals */
+export const PolicyCanAccessVitalsInputSchema = z.object({
+  agent_id: z.string().min(1).describe("Calling agent identifier."),
+  node_id: z.string().min(1).describe("Target sensing node."),
+  vital: z
+    .enum(["breathing", "heart_rate", "all"])
+    .describe("Which vital the agent is requesting."),
+});
+
+/** ruview.policy.can_query_presence */
+export const PolicyCanQueryPresenceInputSchema = z.object({
+  agent_id: z.string().min(1),
+  scope: z
+    .enum(["node", "fleet"])
+    .describe("node = single node; fleet = all nodes / aggregated count."),
+  node_id: NodeIdSchema,
+  zone: z
+    .string()
+    .optional()
+    .describe("Named zone within a node (e.g. 'living_room')."),
+});
+
+/** ruview.policy.can_subscribe */
+export const PolicyCanSubscribeInputSchema = z.object({
+  agent_id: z.string().min(1),
+  topic: z
+    .string()
+    .min(1)
+    .describe("MQTT topic or tool name the agent wishes to subscribe to."),
+  duration_s: DurationSSchema,
+});
+
+/** ruview.policy.redact_identity_fields */
+export const PolicyRedactIdentityFieldsInputSchema = z.object({
+  payload: z.record(z.unknown()).describe("Tool return value to redact."),
+  agent_id: z.string().min(1),
+});
+
+/** ruview.policy.audit_log */
+export const PolicyAuditLogInputSchema = z.object({
+  agent_id: z.string().optional().describe("Filter to a specific agent."),
+  since_ts: z
+    .number()
+    .optional()
+    .describe("Return events after this Unix timestamp (ms)."),
+});
+
+// ── Catalog ───────────────────────────────────────────────────────────────
+
+/**
+ * Single source of truth: every tool name in the ADR-124 §4.1 + §4.1a catalog.
+ * The schema-coverage test asserts this list exactly matches the exported schemas.
+ */
+export const TOOL_NAMES = [
+  // §4.1 — 15 sensing tools
+  "ruview.presence.now",
+  "ruview.vitals.get_breathing",
+  "ruview.vitals.get_heart_rate",
+  "ruview.vitals.get_all",
+  "ruview.pose.latest",
+  "ruview.pose.subscribe",
+  "ruview.primitives.get",
+  "ruview.primitives.list_active",
+  "ruview.primitives.subscribe",
+  "ruview.bfld.last_scan",
+  "ruview.bfld.subscribe",
+  "ruview.node.list",
+  "ruview.node.status",
+  "ruview.vector.search_pose",
+  "ruview.vector.store_pose",
+  // §4.1a — 5 policy tools
+  "ruview.policy.can_access_vitals",
+  "ruview.policy.can_query_presence",
+  "ruview.policy.can_subscribe",
+  "ruview.policy.redact_identity_fields",
+  "ruview.policy.audit_log",
+] as const;
+
+export type ToolName = (typeof TOOL_NAMES)[number];
+
+/**
+ * Map from tool name → its Zod input schema. Used by the MCP server's
+ * CallTool handler for uniform schema-validation before dispatch.
+ */
+export const TOOL_INPUT_SCHEMAS: Record<ToolName, z.ZodTypeAny> = {
+  "ruview.presence.now": PresenceNowInputSchema,
+  "ruview.vitals.get_breathing": VitalsGetBreathingInputSchema,
+  "ruview.vitals.get_heart_rate": VitalsGetHeartRateInputSchema,
+  "ruview.vitals.get_all": VitalsGetAllInputSchema,
+  "ruview.pose.latest": PoseLatestInputSchema,
+  "ruview.pose.subscribe": PoseSubscribeInputSchema,
+  "ruview.primitives.get": PrimitivesGetInputSchema,
+  "ruview.primitives.list_active": PrimitivesListActiveInputSchema,
+  "ruview.primitives.subscribe": PrimitivesSubscribeInputSchema,
+  "ruview.bfld.last_scan": BfldLastScanInputSchema,
+  "ruview.bfld.subscribe": BfldSubscribeInputSchema,
+  "ruview.node.list": NodeListInputSchema,
+  "ruview.node.status": NodeStatusInputSchema,
+  "ruview.vector.search_pose": VectorSearchPoseInputSchema,
+  "ruview.vector.store_pose": VectorStorePoseInputSchema,
+  "ruview.policy.can_access_vitals": PolicyCanAccessVitalsInputSchema,
+  "ruview.policy.can_query_presence": PolicyCanQueryPresenceInputSchema,
+  "ruview.policy.can_subscribe": PolicyCanSubscribeInputSchema,
+  "ruview.policy.redact_identity_fields": PolicyRedactIdentityFieldsInputSchema,
+  "ruview.policy.audit_log": PolicyAuditLogInputSchema,
+};
diff --git a/tools/ruview-mcp/tests/schemas.test.ts b/tools/ruview-mcp/tests/schemas.test.ts
new file mode 100644
index 00000000..32c995bb
--- /dev/null
+++ b/tools/ruview-mcp/tests/schemas.test.ts
@@ -0,0 +1,208 @@
+/**
+ * ADR-124 §4.1 / §4.1a schema coverage tests.
+ *
+ * Guards:
+ *  1. Every catalogued tool name appears in TOOL_NAMES and TOOL_INPUT_SCHEMAS.
+ *  2. TOOL_INPUT_SCHEMAS has no extra (undocumented) keys.
+ *  3. Each schema accepts its documented happy-path input without throwing.
+ *  4. Each schema rejects structurally invalid input (Zod parse failure).
+ *  5. Shared sub-schemas (NodeId, DurationS, SemanticPrimitiveKind) enforce
+ *     their documented constraints.
+ */
+
+import {
+  TOOL_NAMES,
+  TOOL_INPUT_SCHEMAS,
+  SemanticPrimitiveKindSchema,
+  DurationSSchema,
+  NodeIdSchema,
+  PosePersonResultSchema,
+  PresenceNowInputSchema,
+  VitalsGetBreathingInputSchema,
+  PrimitivesGetInputSchema,
+  BfldLastScanInputSchema,
+  NodeStatusInputSchema,
+  VectorSearchPoseInputSchema,
+  VectorStorePoseInputSchema,
+  PolicyCanAccessVitalsInputSchema,
+  PolicyCanSubscribeInputSchema,
+  PolicyRedactIdentityFieldsInputSchema,
+} from "../src/schemas/index.js";
+
+// ── 1. Catalog completeness ────────────────────────────────────────────────
+
+describe("TOOL_NAMES catalog (ADR-124 §4.1 + §4.1a)", () => {
+  const EXPECTED_COUNT = 20; // 15 sensing + 5 policy
+
+  it("contains exactly 20 tools", () => {
+    expect(TOOL_NAMES).toHaveLength(EXPECTED_COUNT);
+  });
+
+  it("contains all 15 §4.1 sensing tool names", () => {
+    const sensing = [
+      "ruview.presence.now",
+      "ruview.vitals.get_breathing",
+      "ruview.vitals.get_heart_rate",
+      "ruview.vitals.get_all",
+      "ruview.pose.latest",
+      "ruview.pose.subscribe",
+      "ruview.primitives.get",
+      "ruview.primitives.list_active",
+      "ruview.primitives.subscribe",
+      "ruview.bfld.last_scan",
+      "ruview.bfld.subscribe",
+      "ruview.node.list",
+      "ruview.node.status",
+      "ruview.vector.search_pose",
+      "ruview.vector.store_pose",
+    ];
+    for (const name of sensing) {
+      expect(TOOL_NAMES).toContain(name);
+    }
+  });
+
+  it("contains all 5 §4.1a policy tool names", () => {
+    const policy = [
+      "ruview.policy.can_access_vitals",
+      "ruview.policy.can_query_presence",
+      "ruview.policy.can_subscribe",
+      "ruview.policy.redact_identity_fields",
+      "ruview.policy.audit_log",
+    ];
+    for (const name of policy) {
+      expect(TOOL_NAMES).toContain(name);
+    }
+  });
+
+  it("TOOL_INPUT_SCHEMAS has a schema for every catalogued tool name", () => {
+    for (const name of TOOL_NAMES) {
+      // Use Object.prototype.hasOwnProperty to avoid Jest's dotted-path
+      // interpretation of toHaveProperty (dots = nested path in Jest).
+      expect(Object.prototype.hasOwnProperty.call(TOOL_INPUT_SCHEMAS, name)).toBe(true);
+      expect(TOOL_INPUT_SCHEMAS[name]).toBeDefined();
+    }
+  });
+
+  it("TOOL_INPUT_SCHEMAS has no extra keys beyond the catalog", () => {
+    const schemaKeys = Object.keys(TOOL_INPUT_SCHEMAS).sort();
+    const catalogKeys = [...TOOL_NAMES].sort();
+    expect(schemaKeys).toEqual(catalogKeys);
+  });
+});
+
+// ── 2. Happy-path parse ────────────────────────────────────────────────────
+
+describe("Schema happy-path acceptance", () => {
+  it("PresenceNow — accepts empty object (node_id optional)", () => {
+    expect(() => PresenceNowInputSchema.parse({})).not.toThrow();
+  });
+
+  it("PresenceNow — accepts object with node_id", () => {
+    const r = PresenceNowInputSchema.parse({ node_id: "node-abc" });
+    expect(r.node_id).toBe("node-abc");
+  });
+
+  it("VitalsGetBreathing — accepts window_s and node_id", () => {
+    const r = VitalsGetBreathingInputSchema.parse({ window_s: 30, node_id: "n1" });
+    expect(r.window_s).toBe(30);
+  });
+
+  it("PrimitivesGet — accepts valid primitive kind", () => {
+    const r = PrimitivesGetInputSchema.parse({ primitive: "fall_detected" });
+    expect(r.primitive).toBe("fall_detected");
+  });
+
+  it("BfldLastScan — accepts empty object", () => {
+    expect(() => BfldLastScanInputSchema.parse({})).not.toThrow();
+  });
+
+  it("NodeStatus — accepts node_id string", () => {
+    const r = NodeStatusInputSchema.parse({ node_id: "cognitum-seed-1" });
+    expect(r.node_id).toBe("cognitum-seed-1");
+  });
+
+  it("VectorSearchPose — applies default k=10", () => {
+    const r = VectorSearchPoseInputSchema.parse({ query_embedding: [0.1, 0.2, 0.3] });
+    expect(r.k).toBe(10);
+  });
+
+  it("VectorStorePose — accepts a valid 17-keypoint pose", () => {
+    const kpts = Array.from({ length: 17 }, (_, i) => [i * 0.05, i * 0.03] as [number, number]);
+    const r = VectorStorePoseInputSchema.parse({
+      pose: { keypoints: kpts, confidence: 0.92 },
+      node_id: "node-x",
+    });
+    expect(r.pose.keypoints).toHaveLength(17);
+  });
+
+  it("PolicyCanAccessVitals — accepts valid vital value", () => {
+    const r = PolicyCanAccessVitalsInputSchema.parse({
+      agent_id: "agent-007",
+      node_id: "node-1",
+      vital: "heart_rate",
+    });
+    expect(r.vital).toBe("heart_rate");
+  });
+
+  it("PolicyCanSubscribe — accepts valid duration_s", () => {
+    const r = PolicyCanSubscribeInputSchema.parse({
+      agent_id: "agent-007",
+      topic: "ruview.vitals.get_all",
+      duration_s: 300,
+    });
+    expect(r.duration_s).toBe(300);
+  });
+
+  it("PolicyRedactIdentityFields — accepts arbitrary payload record", () => {
+    const r = PolicyRedactIdentityFieldsInputSchema.parse({
+      payload: { sta_mac: "AA:BB:CC:DD:EE:FF", n_persons: 2 },
+      agent_id: "agent-007",
+    });
+    expect(r.payload).toHaveProperty("sta_mac");
+  });
+});
+
+// ── 3. Constraint rejection ────────────────────────────────────────────────
+
+describe("Schema constraint enforcement", () => {
+  it("NodeIdSchema — rejects empty string", () => {
+    expect(() => NodeIdSchema.parse("")).toThrow();
+  });
+
+  it("DurationSSchema — rejects zero", () => {
+    expect(() => DurationSSchema.parse(0)).toThrow();
+  });
+
+  it("DurationSSchema — rejects value > 3600", () => {
+    expect(() => DurationSSchema.parse(3601)).toThrow();
+  });
+
+  it("SemanticPrimitiveKind — rejects unknown primitive", () => {
+    expect(() => SemanticPrimitiveKindSchema.parse("unknown_primitive")).toThrow();
+  });
+
+  it("PosePersonResult — rejects keypoints array with wrong length", () => {
+    const badKpts = Array.from({ length: 5 }, () => [0, 0] as [number, number]);
+    expect(() => PosePersonResultSchema.parse({ keypoints: badKpts, confidence: 0.9 })).toThrow();
+  });
+
+  it("VectorSearchPose — rejects k > 100", () => {
+    expect(() =>
+      VectorSearchPoseInputSchema.parse({ query_embedding: [0.1], k: 101 })
+    ).toThrow();
+  });
+
+  it("PolicyCanAccessVitals — rejects unknown vital value", () => {
+    expect(() =>
+      PolicyCanAccessVitalsInputSchema.parse({
+        agent_id: "a",
+        node_id: "n",
+        vital: "temperature",
+      })
+    ).toThrow();
+  });
+
+  it("NodeStatus — rejects missing node_id", () => {
+    expect(() => NodeStatusInputSchema.parse({})).toThrow();
+  });
+});