(mess) Stuffing commit.

docs/examples/minimal.ts

@@ -6,18 +6,27 @@ const fastify = Fastify()
 // APOPHIS auto-registers @fastify/swagger
 await fastify.register(apophisPlugin, {})
 
-fastify.get('/health', {
+// Behavioral contract: what you send is what you get back.
+// This is not a structural test — the schema already validates shape.
+// This checks that the server does not mutate or drop fields.
+fastify.post('/echo', {
   schema: {
     'x-category': 'observer',
-    'x-ensures': ['status:200'],
+    'x-ensures': [
+      'response_body(this) == request_body(this)'
+    ],
+    body: {
+      type: 'object',
+      properties: { message: { type: 'string' } }
+    },
     response: {
       200: {
         type: 'object',
-        properties: { status: { type: 'string' } }
+        properties: { message: { type: 'string' } }
       }
     }
   }
-}, async () => ({ status: 'ok' }))
+}, async (req) => req.body)
 
 await fastify.ready()