diff --git a/docs/TECH/ARCH_LAYER_FOUNDATION.md b/docs/TECH/ARCH_LAYER_FOUNDATION.md
index ba701ae..86b1012 100644
--- a/docs/TECH/ARCH_LAYER_FOUNDATION.md
+++ b/docs/TECH/ARCH_LAYER_FOUNDATION.md
@@ -91,6 +91,14 @@ Tests:
 - `llm_normalizer/backend/tests/addressCapabilityPolicy.test.ts`
 - `llm_normalizer/backend/tests/addressNavigationState.test.ts`
 - `llm_normalizer/backend/tests/sessionBackwardCompat.test.ts` (extended)
+- `llm_normalizer/backend/tests/addressRouteBaseline.test.ts`
+
+Route baseline contract:
+
+- `docs/TECH/address_route_baseline_v1.json`
+- loader: `llm_normalizer/backend/src/services/addressRouteBaseline.ts`
+
+This baseline freezes capability mapping for key intents and acts as anti-regression control when routing evolves.
 
 ## Why This Is a Foundation, Not a Patch
 
diff --git a/docs/TECH/address_route_baseline_v1.json b/docs/TECH/address_route_baseline_v1.json
new file mode 100644
index 0000000..4974f98
--- /dev/null
+++ b/docs/TECH/address_route_baseline_v1.json
@@ -0,0 +1,66 @@
+{
+  "schema_version": "address_route_baseline_v1",
+  "updated_at": "2026-04-12T12:00:00.000Z",
+  "entries": [
+    {
+      "intent": "payables_confirmed_as_of_date",
+      "capability_id": "confirmed_payables_as_of_date",
+      "capability_layer": "compute",
+      "capability_route_mode": "exact"
+    },
+    {
+      "intent": "list_payables_counterparties",
+      "capability_id": "payables_candidates_list",
+      "capability_layer": "compute",
+      "capability_route_mode": "heuristic"
+    },
+    {
+      "intent": "list_receivables_counterparties",
+      "capability_id": "receivables_candidates_list",
+      "capability_layer": "compute",
+      "capability_route_mode": "heuristic"
+    },
+    {
+      "intent": "account_balance_snapshot",
+      "capability_id": "account_balance_exact",
+      "capability_layer": "compute",
+      "capability_route_mode": "exact"
+    },
+    {
+      "intent": "documents_forming_balance",
+      "capability_id": "account_balance_exact",
+      "capability_layer": "compute",
+      "capability_route_mode": "exact"
+    },
+    {
+      "intent": "list_documents_by_counterparty",
+      "capability_id": "documents_drilldown",
+      "capability_layer": "navigation",
+      "capability_route_mode": "exact"
+    },
+    {
+      "intent": "list_documents_by_contract",
+      "capability_id": "documents_drilldown",
+      "capability_layer": "navigation",
+      "capability_route_mode": "exact"
+    },
+    {
+      "intent": "list_contracts_by_counterparty",
+      "capability_id": "contracts_drilldown",
+      "capability_layer": "navigation",
+      "capability_route_mode": "exact"
+    },
+    {
+      "intent": "bank_operations_by_counterparty",
+      "capability_id": "bank_operations_drilldown",
+      "capability_layer": "navigation",
+      "capability_route_mode": "exact"
+    },
+    {
+      "intent": "bank_operations_by_contract",
+      "capability_id": "bank_operations_drilldown",
+      "capability_layer": "navigation",
+      "capability_route_mode": "exact"
+    }
+  ]
+}
diff --git a/llm_normalizer/backend/dist/services/addressRouteBaseline.js b/llm_normalizer/backend/dist/services/addressRouteBaseline.js
new file mode 100644
index 0000000..e633493
--- /dev/null
+++ b/llm_normalizer/backend/dist/services/addressRouteBaseline.js
@@ -0,0 +1,64 @@
+"use strict";
+var __importDefault = (this && this.__importDefault) || function (mod) {
+    return (mod && mod.__esModule) ? mod : { "default": mod };
+};
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.loadAddressRouteBaselineContract = loadAddressRouteBaselineContract;
+const fs_1 = __importDefault(require("fs"));
+const path_1 = __importDefault(require("path"));
+const BASELINE_FILE = path_1.default.resolve(__dirname, "..", "..", "..", "..", "docs", "TECH", "address_route_baseline_v1.json");
+function toObject(value) {
+    if (!value || typeof value !== "object" || Array.isArray(value)) {
+        return null;
+    }
+    return value;
+}
+function toNonEmptyString(value) {
+    if (typeof value !== "string") {
+        return null;
+    }
+    const trimmed = value.trim();
+    return trimmed.length > 0 ? trimmed : null;
+}
+function parseEntry(value) {
+    const object = toObject(value);
+    if (!object) {
+        return null;
+    }
+    const intent = toNonEmptyString(object.intent);
+    const capabilityId = toNonEmptyString(object.capability_id);
+    const layer = toNonEmptyString(object.capability_layer);
+    const routeMode = toNonEmptyString(object.capability_route_mode);
+    if (!intent || !capabilityId || !layer || !routeMode) {
+        return null;
+    }
+    return {
+        intent,
+        capability_id: capabilityId,
+        capability_layer: layer,
+        capability_route_mode: routeMode
+    };
+}
+function loadAddressRouteBaselineContract() {
+    const raw = fs_1.default.readFileSync(BASELINE_FILE, "utf-8");
+    const parsed = JSON.parse(raw);
+    const root = toObject(parsed);
+    if (!root) {
+        throw new Error("address_route_baseline_v1: invalid root payload");
+    }
+    const schemaVersion = toNonEmptyString(root.schema_version);
+    if (schemaVersion !== "address_route_baseline_v1") {
+        throw new Error(`address_route_baseline_v1: unexpected schema version '${schemaVersion ?? "null"}'`);
+    }
+    const updatedAt = toNonEmptyString(root.updated_at) ?? new Date().toISOString();
+    const entriesRaw = Array.isArray(root.entries) ? root.entries : [];
+    const entries = entriesRaw.map(parseEntry).filter((entry) => entry !== null);
+    if (entries.length === 0) {
+        throw new Error("address_route_baseline_v1: no valid entries");
+    }
+    return {
+        schema_version: "address_route_baseline_v1",
+        updated_at: updatedAt,
+        entries
+    };
+}
diff --git a/llm_normalizer/backend/src/services/addressRouteBaseline.ts b/llm_normalizer/backend/src/services/addressRouteBaseline.ts
new file mode 100644
index 0000000..f2da83b
--- /dev/null
+++ b/llm_normalizer/backend/src/services/addressRouteBaseline.ts
@@ -0,0 +1,77 @@
+import fs from "fs";
+import path from "path";
+import type { AddressCapabilityLayer, AddressCapabilityRouteMode, AddressIntent } from "../types/addressQuery";
+
+export interface AddressRouteBaselineEntry {
+  intent: AddressIntent;
+  capability_id: string;
+  capability_layer: AddressCapabilityLayer;
+  capability_route_mode: AddressCapabilityRouteMode;
+}
+
+export interface AddressRouteBaselineContract {
+  schema_version: "address_route_baseline_v1";
+  updated_at: string;
+  entries: AddressRouteBaselineEntry[];
+}
+
+const BASELINE_FILE = path.resolve(__dirname, "..", "..", "..", "..", "docs", "TECH", "address_route_baseline_v1.json");
+
+function toObject(value: unknown): Record<string, unknown> | null {
+  if (!value || typeof value !== "object" || Array.isArray(value)) {
+    return null;
+  }
+  return value as Record<string, unknown>;
+}
+
+function toNonEmptyString(value: unknown): string | null {
+  if (typeof value !== "string") {
+    return null;
+  }
+  const trimmed = value.trim();
+  return trimmed.length > 0 ? trimmed : null;
+}
+
+function parseEntry(value: unknown): AddressRouteBaselineEntry | null {
+  const object = toObject(value);
+  if (!object) {
+    return null;
+  }
+  const intent = toNonEmptyString(object.intent) as AddressIntent | null;
+  const capabilityId = toNonEmptyString(object.capability_id);
+  const layer = toNonEmptyString(object.capability_layer) as AddressCapabilityLayer | null;
+  const routeMode = toNonEmptyString(object.capability_route_mode) as AddressCapabilityRouteMode | null;
+  if (!intent || !capabilityId || !layer || !routeMode) {
+    return null;
+  }
+  return {
+    intent,
+    capability_id: capabilityId,
+    capability_layer: layer,
+    capability_route_mode: routeMode
+  };
+}
+
+export function loadAddressRouteBaselineContract(): AddressRouteBaselineContract {
+  const raw = fs.readFileSync(BASELINE_FILE, "utf-8");
+  const parsed = JSON.parse(raw) as unknown;
+  const root = toObject(parsed);
+  if (!root) {
+    throw new Error("address_route_baseline_v1: invalid root payload");
+  }
+  const schemaVersion = toNonEmptyString(root.schema_version);
+  if (schemaVersion !== "address_route_baseline_v1") {
+    throw new Error(`address_route_baseline_v1: unexpected schema version '${schemaVersion ?? "null"}'`);
+  }
+  const updatedAt = toNonEmptyString(root.updated_at) ?? new Date().toISOString();
+  const entriesRaw = Array.isArray(root.entries) ? root.entries : [];
+  const entries = entriesRaw.map(parseEntry).filter((entry): entry is AddressRouteBaselineEntry => entry !== null);
+  if (entries.length === 0) {
+    throw new Error("address_route_baseline_v1: no valid entries");
+  }
+  return {
+    schema_version: "address_route_baseline_v1",
+    updated_at: updatedAt,
+    entries
+  };
+}
diff --git a/llm_normalizer/backend/tests/addressRouteBaseline.test.ts b/llm_normalizer/backend/tests/addressRouteBaseline.test.ts
new file mode 100644
index 0000000..aaabacc
--- /dev/null
+++ b/llm_normalizer/backend/tests/addressRouteBaseline.test.ts
@@ -0,0 +1,19 @@
+import { describe, expect, it } from "vitest";
+import { loadAddressRouteBaselineContract } from "../src/services/addressRouteBaseline";
+import { resolveAddressCapabilityRouteDecision } from "../src/services/addressCapabilityPolicy";
+
+describe("address route baseline contract", () => {
+  it("keeps capability route mapping aligned with frozen baseline", () => {
+    const baseline = loadAddressRouteBaselineContract();
+    expect(baseline.schema_version).toBe("address_route_baseline_v1");
+    expect(Array.isArray(baseline.entries)).toBe(true);
+    expect(baseline.entries.length).toBeGreaterThan(0);
+
+    for (const entry of baseline.entries) {
+      const decision = resolveAddressCapabilityRouteDecision(entry.intent);
+      expect(decision.capability_id).toBe(entry.capability_id);
+      expect(decision.capability_layer).toBe(entry.capability_layer);
+      expect(decision.capability_route_mode).toBe(entry.capability_route_mode);
+    }
+  });
+});