diff --git a/src/openapi/types/resource-role-create.ts b/src/openapi/types/resource-role-create.ts
index a66bbad3..1257d6a6 100644
--- a/src/openapi/types/resource-role-create.ts
+++ b/src/openapi/types/resource-role-create.ts
@@ -52,6 +52,12 @@ export interface ResourceRoleCreate {
    * @memberof ResourceRoleCreate
    */
   attributes?: object;
+  /**
+   * list of role keys that define what roles this role extends. In other words: this role will automatically inherit all the permissions of the given roles in this list.
+   * @type {Array<string>}
+   * @memberof ResourceRoleCreate
+   */
+  extends?: Array<string>;
   /**
    *
    * @type {GrantedTo1}
diff --git a/src/openapi/types/resource-role-read.ts b/src/openapi/types/resource-role-read.ts
index f175f30d..506459ec 100644
--- a/src/openapi/types/resource-role-read.ts
+++ b/src/openapi/types/resource-role-read.ts
@@ -46,6 +46,12 @@ export interface ResourceRoleRead {
    * @memberof ResourceRoleRead
    */
   attributes?: object;
+  /**
+   * list of role keys that define what roles this role extends. In other words: this role will automatically inherit all the permissions of the given roles in this list.
+   * @type {Array<string>}
+   * @memberof ResourceRoleRead
+   */
+  extends?: Array<string>;
   /**
    *
    * @type {GrantedTo2}
diff --git a/src/openapi/types/resource-role-update.ts b/src/openapi/types/resource-role-update.ts
index 421c7aa7..230be018 100644
--- a/src/openapi/types/resource-role-update.ts
+++ b/src/openapi/types/resource-role-update.ts
@@ -46,6 +46,12 @@ export interface ResourceRoleUpdate {
    * @memberof ResourceRoleUpdate
    */
   attributes?: object;
+  /**
+   * list of role keys that define what roles this role extends. In other words: this role will automatically inherit all the permissions of the given roles in this list.
+   * @type {Array<string>}
+   * @memberof ResourceRoleUpdate
+   */
+  extends?: Array<string>;
   /**
    *
    * @type {GrantedTo1}
diff --git a/src/openapi/types/role-create.ts b/src/openapi/types/role-create.ts
index 2e5fbc7d..0f9bbca8 100644
--- a/src/openapi/types/role-create.ts
+++ b/src/openapi/types/role-create.ts
@@ -52,6 +52,12 @@ export interface RoleCreate {
    * @memberof RoleCreate
    */
   attributes?: object;
+  /**
+   * list of role keys that define what roles this role extends. In other words: this role will automatically inherit all the permissions of the given roles in this list.
+   * @type {Array<string>}
+   * @memberof RoleCreate
+   */
+  extends?: Array<string>;
   /**
    *
    * @type {GrantedTo1}
diff --git a/src/openapi/types/role-read.ts b/src/openapi/types/role-read.ts
index dd47e7ce..26863dfa 100644
--- a/src/openapi/types/role-read.ts
+++ b/src/openapi/types/role-read.ts
@@ -46,6 +46,12 @@ export interface RoleRead {
    * @memberof RoleRead
    */
   attributes?: object;
+  /**
+   * list of role keys that define what roles this role extends. In other words: this role will automatically inherit all the permissions of the given roles in this list.
+   * @type {Array<string>}
+   * @memberof RoleRead
+   */
+  extends?: Array<string>;
   /**
    *
    * @type {GrantedTo}
diff --git a/src/openapi/types/role-update.ts b/src/openapi/types/role-update.ts
index eea11de1..23ca51da 100644
--- a/src/openapi/types/role-update.ts
+++ b/src/openapi/types/role-update.ts
@@ -46,6 +46,12 @@ export interface RoleUpdate {
    * @memberof RoleUpdate
    */
   attributes?: object;
+  /**
+   * list of role keys that define what roles this role extends. In other words: this role will automatically inherit all the permissions of the given roles in this list.
+   * @type {Array<string>}
+   * @memberof RoleUpdate
+   */
+  extends?: Array<string>;
   /**
    *
    * @type {GrantedTo1}
diff --git a/src/tests/unit/role-extends.spec.ts b/src/tests/unit/role-extends.spec.ts
new file mode 100644
index 00000000..b4d13ea5
--- /dev/null
+++ b/src/tests/unit/role-extends.spec.ts
@@ -0,0 +1,142 @@
+import test from 'ava';
+
+import { Permit } from '../../index';
+
+type RoleCreate = Parameters<Permit['api']['roles']['create']>[0];
+type RoleRead = Awaited<ReturnType<Permit['api']['roles']['get']>>;
+type RoleUpdate = Parameters<Permit['api']['roles']['update']>[1];
+type ResourceRoleCreate = Parameters<Permit['api']['resourceRoles']['create']>[1];
+type ResourceRoleRead = Awaited<ReturnType<Permit['api']['resourceRoles']['get']>>;
+type ResourceRoleUpdate = Parameters<Permit['api']['resourceRoles']['update']>[2];
+
+type IsExact<A, B> = (<T>() => T extends A ? 1 : 2) extends <T>() => T extends B ? 1 : 2
+  ? true
+  : false;
+type Assert<T extends true> = T;
+type Inheritance = { extends?: Array<string> };
+
+// yarn test:unit runs build:types before AVA. Pick preserves the optional modifier, and exact
+// equality rejects any, null, non-array values, and a required property (even with undefined).
+export type RoleInheritanceContracts = [
+  Assert<IsExact<Pick<RoleCreate, 'extends'>, Inheritance>>,
+  Assert<IsExact<Pick<RoleRead, 'extends'>, Inheritance>>,
+  Assert<IsExact<Pick<RoleUpdate, 'extends'>, Inheritance>>,
+  Assert<IsExact<Pick<ResourceRoleCreate, 'extends'>, Inheritance>>,
+  Assert<IsExact<Pick<ResourceRoleRead, 'extends'>, Inheritance>>,
+  Assert<IsExact<Pick<ResourceRoleUpdate, 'extends'>, Inheritance>>,
+];
+
+function createClient(inheritance: Inheritance) {
+  const permit = new Permit({
+    token: 'test',
+    apiUrl: 'https://api.permit.io',
+    log: { level: 'silent' },
+  });
+  const requests: Array<{ method: string | undefined; url: string | undefined; body: unknown }> =
+    [];
+  const role: ResourceRoleRead = {
+    key: 'editor',
+    name: 'Editor',
+    id: 'role-id',
+    organization_id: 'org',
+    project_id: 'proj',
+    environment_id: 'env',
+    resource_id: 'resource-id',
+    resource: 'doc',
+    created_at: '2026-01-01T00:00:00Z',
+    updated_at: '2026-01-01T00:00:00Z',
+    ...inheritance,
+  };
+  permit.config.axiosInstance.defaults.adapter = async (config) => {
+    const isScopeRequest = config.url === 'https://api.permit.io/v2/api-key/scope';
+    if (!isScopeRequest) {
+      requests.push({
+        method: config.method,
+        url: config.url,
+        body: config.data === undefined ? undefined : JSON.parse(config.data),
+      });
+    }
+    return {
+      status: 200,
+      statusText: 'OK',
+      headers: {},
+      config,
+      data: isScopeRequest
+        ? { organization_id: 'org', project_id: 'proj', environment_id: 'env' }
+        : { ...role },
+    };
+  };
+  return { permit, requests };
+}
+
+const cases: Array<{ name: string; inheritance: Inheritance }> = [
+  { name: 'multiple inherited roles', inheritance: { extends: ['viewer', 'auditor'] } },
+  { name: 'empty inheritance', inheritance: { extends: [] } },
+  { name: 'omitted inheritance', inheritance: {} },
+];
+
+for (const { name, inheritance } of cases) {
+  test(`roles create/update/get preserve ${name}`, async (t) => {
+    const { permit, requests } = createClient(inheritance);
+    const created = await permit.api.roles.create({
+      key: 'editor',
+      name: 'Editor',
+      ...inheritance,
+    });
+    const updated = await permit.api.roles.update('editor', { ...inheritance });
+    const fetched = await permit.api.roles.get('editor');
+
+    t.deepEqual(created.extends, inheritance.extends);
+    t.deepEqual(updated.extends, inheritance.extends);
+    t.deepEqual(fetched.extends, inheritance.extends);
+    t.deepEqual(requests, [
+      {
+        method: 'post',
+        url: 'https://api.permit.io/v2/schema/proj/env/roles',
+        body: { key: 'editor', name: 'Editor', ...inheritance },
+      },
+      {
+        method: 'patch',
+        url: 'https://api.permit.io/v2/schema/proj/env/roles/editor',
+        body: { ...inheritance },
+      },
+      {
+        method: 'get',
+        url: 'https://api.permit.io/v2/schema/proj/env/roles/editor',
+        body: undefined,
+      },
+    ]);
+  });
+
+  test(`resource roles create/update/get preserve ${name}`, async (t) => {
+    const { permit, requests } = createClient(inheritance);
+    const created = await permit.api.resourceRoles.create('doc', {
+      key: 'editor',
+      name: 'Editor',
+      ...inheritance,
+    });
+    const updated = await permit.api.resourceRoles.update('doc', 'editor', { ...inheritance });
+    const fetched = await permit.api.resourceRoles.get('doc', 'editor');
+
+    t.deepEqual(created.extends, inheritance.extends);
+    t.deepEqual(updated.extends, inheritance.extends);
+    t.deepEqual(fetched.extends, inheritance.extends);
+    t.deepEqual(requests, [
+      {
+        method: 'post',
+        url: 'https://api.permit.io/v2/schema/proj/env/resources/doc/roles',
+        body: { key: 'editor', name: 'Editor', ...inheritance },
+      },
+      {
+        method: 'patch',
+        url: 'https://api.permit.io/v2/schema/proj/env/resources/doc/roles/editor',
+        body: { ...inheritance },
+      },
+      {
+        method: 'get',
+        url: 'https://api.permit.io/v2/schema/proj/env/resources/doc/roles/editor',
+        body: undefined,
+      },
+    ]);
+  });
+}