diff --git a/src/plugins/contracts/provider-family-plugin-tests.test.ts b/src/plugins/contracts/provider-family-plugin-tests.test.ts
new file mode 100644
index 00000000000..5fa71ed719e
--- /dev/null
+++ b/src/plugins/contracts/provider-family-plugin-tests.test.ts
@@ -0,0 +1,126 @@
+import { readdirSync, readFileSync } from "node:fs";
+import { dirname, relative, resolve, sep } from "node:path";
+import { fileURLToPath } from "node:url";
+import { describe, expect, it } from "vitest";
+import { BUNDLED_PLUGIN_ROOT_DIR, bundledPluginRoot } from "../../../test/helpers/bundled-plugin-paths.js";
+
+type SharedFamilyHookKind = "replay" | "stream" | "tool-compat";
+
+type SharedFamilyProviderInventory = {
+  hookKinds: Set<SharedFamilyHookKind>;
+  sourceFiles: Set<string>;
+};
+
+const SRC_ROOT = resolve(dirname(fileURLToPath(import.meta.url)), "../..");
+const REPO_ROOT = resolve(SRC_ROOT, "..");
+const EXTENSIONS_DIR = resolve(REPO_ROOT, BUNDLED_PLUGIN_ROOT_DIR);
+const SHARED_FAMILY_HOOK_PATTERNS: ReadonlyArray<{
+  kind: SharedFamilyHookKind;
+  regex: RegExp;
+}> = [
+  { kind: "replay", regex: /\bbuildProviderReplayFamilyHooks\s*\(/u },
+  { kind: "stream", regex: /\bbuildProviderStreamFamilyHooks\s*\(/u },
+  { kind: "tool-compat", regex: /\bbuildProviderToolCompatFamilyHooks\s*\(/u },
+];
+const PROVIDER_BOUNDARY_TEST_SIGNALS = [
+  /\bregister(?:Single)?ProviderPlugin\s*\(/u,
+  /\bcreateTestPluginApi\s*\(/u,
+] as const;
+
+function toRepoRelative(path: string): string {
+  return relative(REPO_ROOT, path).split(sep).join("/");
+}
+
+function listFiles(dir: string): string[] {
+  const files: string[] = [];
+
+  for (const entry of readdirSync(dir, { withFileTypes: true })) {
+    if (entry.name === "dist" || entry.name === "node_modules") {
+      continue;
+    }
+    const entryPath = resolve(dir, entry.name);
+    if (entry.isDirectory()) {
+      files.push(...listFiles(entryPath));
+      continue;
+    }
+    files.push(entryPath);
+  }
+
+  return files;
+}
+
+function resolveBundledPluginId(filePath: string): string | null {
+  const relativePath = relative(EXTENSIONS_DIR, filePath).split(sep).join("/");
+  const [pluginId] = relativePath.split("/");
+  return pluginId || null;
+}
+
+function collectSharedFamilyProviders(): Map<string, SharedFamilyProviderInventory> {
+  const inventory = new Map<string, SharedFamilyProviderInventory>();
+
+  for (const filePath of listFiles(EXTENSIONS_DIR)) {
+    if (!filePath.endsWith(".ts") || filePath.endsWith(".test.ts")) {
+      continue;
+    }
+    const source = readFileSync(filePath, "utf8");
+    const matchedKinds = SHARED_FAMILY_HOOK_PATTERNS.filter(({ regex }) => regex.test(source));
+    if (matchedKinds.length === 0) {
+      continue;
+    }
+    const pluginId = resolveBundledPluginId(filePath);
+    if (!pluginId) {
+      continue;
+    }
+    const entry = inventory.get(pluginId) ?? {
+      hookKinds: new Set<SharedFamilyHookKind>(),
+      sourceFiles: new Set<string>(),
+    };
+    for (const { kind } of matchedKinds) {
+      entry.hookKinds.add(kind);
+    }
+    entry.sourceFiles.add(toRepoRelative(filePath));
+    inventory.set(pluginId, entry);
+  }
+
+  return inventory;
+}
+
+function collectProviderBoundaryTests(): Map<string, Set<string>> {
+  const inventory = new Map<string, Set<string>>();
+
+  for (const filePath of listFiles(EXTENSIONS_DIR)) {
+    if (!filePath.endsWith(".test.ts")) {
+      continue;
+    }
+    const source = readFileSync(filePath, "utf8");
+    if (!PROVIDER_BOUNDARY_TEST_SIGNALS.some((signal) => signal.test(source))) {
+      continue;
+    }
+    const pluginId = resolveBundledPluginId(filePath);
+    if (!pluginId) {
+      continue;
+    }
+    const tests = inventory.get(pluginId) ?? new Set<string>();
+    tests.add(toRepoRelative(filePath));
+    inventory.set(pluginId, tests);
+  }
+
+  return inventory;
+}
+
+describe("provider family plugin-boundary inventory", () => {
+  it("keeps shared-family provider hooks covered by at least one plugin-boundary test", () => {
+    const sharedFamilyProviders = collectSharedFamilyProviders();
+    const providerBoundaryTests = collectProviderBoundaryTests();
+
+    const missing = [...sharedFamilyProviders.entries()]
+      .filter(([pluginId]) => !providerBoundaryTests.has(pluginId))
+      .map(([pluginId, inventory]) => {
+        const hookKinds = [...inventory.hookKinds].toSorted().join(", ");
+        const sourceFiles = [...inventory.sourceFiles].toSorted().join(", ");
+        return `${bundledPluginRoot(pluginId)} declares shared ${hookKinds} hooks but has no plugin-boundary provider test. Sources: ${sourceFiles}`;
+      });
+
+    expect(missing).toEqual([]);
+  });
+});