diff --git a/packages/openapi-generator/src/cli.ts b/packages/openapi-generator/src/cli.ts
index 4e33e51e..cf5fe22d 100644
--- a/packages/openapi-generator/src/cli.ts
+++ b/packages/openapi-generator/src/cli.ts
@@ -60,6 +60,13 @@ const app = command({
       short: 'i',
       defaultValue: () => false,
     }),
+    includeUnstable: flag({
+      type: boolean,
+      description: 'include routes marked unstable',
+      long: 'unstable',
+      short: 'u',
+      defaultValue: () => false,
+    }),
     codecFile: option({
       type: optional(string),
       description: 'Custom codec definition file',
diff --git a/packages/openapi-generator/src/openapi.ts b/packages/openapi-generator/src/openapi.ts
index e95638d2..6fc04216 100644
--- a/packages/openapi-generator/src/openapi.ts
+++ b/packages/openapi-generator/src/openapi.ts
@@ -116,6 +116,7 @@ function routeToOpenAPI(route: Route): [string, string, OpenAPIV3.OperationObjec
   const operationId = jsdoc.tags?.operationId;
   const tag = jsdoc.tags?.tag ?? '';
   const isInternal = jsdoc.tags?.private !== undefined;
+  const isUnstable = jsdoc.tags?.unstable !== undefined;
 
   const requestBody =
     route.body === undefined
@@ -137,6 +138,7 @@ function routeToOpenAPI(route: Route): [string, string, OpenAPIV3.OperationObjec
       ...(operationId !== undefined ? { operationId } : {}),
       ...(tag !== '' ? { tags: [tag] } : {}),
       ...(isInternal ? { 'x-internal': true } : {}),
+      ...(isUnstable ? { 'x-unstable': true } : {}),
       parameters: route.parameters.map((p) => {
         // Array types not allowed here
         const schema = schemaToOpenAPI(p.schema);
diff --git a/packages/openapi-generator/test/openapi.test.ts b/packages/openapi-generator/test/openapi.test.ts
index dad2e9a7..a2e9c862 100644
--- a/packages/openapi-generator/test/openapi.test.ts
+++ b/packages/openapi-generator/test/openapi.test.ts
@@ -16,7 +16,7 @@ import {
 async function testCase(
   description: string,
   src: string,
-  expected: OpenAPIV3_1.Document<{ 'x-internal'?: boolean }>,
+  expected: OpenAPIV3_1.Document<{ 'x-internal'?: boolean; 'x-unstable'?: boolean }>,
   expectedErrors: string[] = [],
 ) {
   test(description, async () => {
@@ -106,6 +106,26 @@ export const internalRoute = h.httpRoute({
     200: t.string
   },
 });
+
+/**
+ * An unstable route
+ *
+ * @unstable
+ * @operationId api.v1.unstable
+ * @tag Unstable Routes
+ */
+export const unstableRoute = h.httpRoute({
+  path: '/unstable/foo',
+  method: 'GET',
+  request: h.httpRequest({
+    query: {
+      foo: t.string,
+    },
+  }),
+  response: {
+    200: t.string
+  },
+});
 `;
 
 testCase('simple route', SIMPLE, {
@@ -181,6 +201,36 @@ testCase('simple route', SIMPLE, {
         },
       },
     },
+    '/unstable/foo': {
+      get: {
+        summary: 'An unstable route',
+        operationId: 'api.v1.unstable',
+        tags: ['Unstable Routes'],
+        'x-unstable': true,
+        parameters: [
+          {
+            in: 'query',
+            name: 'foo',
+            required: true,
+            schema: {
+              type: 'string',
+            },
+          },
+        ],
+        responses: {
+          200: {
+            description: 'OK',
+            content: {
+              'application/json': {
+                schema: {
+                  type: 'string',
+                },
+              },
+            },
+          },
+        },
+      },
+    },
   },
   components: {
     schemas: {},