Add story-style examples suite (27 stories + harness + CI) (#2957)

examples/stories/json_response/server.py

@@ -0,0 +1,27 @@
+"""Serve over Streamable HTTP with JSON responses (no SSE stream); HTTP-only, so this exports ``build_app()``.
+
+The 2026-07-28 path is stateless and JSON-only by construction today; the
+``json_response=True`` flag also forces JSON for the legacy (2025-era) branch on
+the same endpoint. Mid-call notifications are dropped.
+"""
+
+from starlette.applications import Starlette
+
+from mcp.server.mcpserver import Context, MCPServer
+from stories._hosting import NO_DNS_REBIND, run_app_from_args
+
+
+def build_app() -> Starlette:
+    mcp = MCPServer("json-response-example")
+
+    @mcp.tool()
+    async def greet(name: str, ctx: Context) -> str:
+        """Report progress mid-call, then return a greeting."""
+        await ctx.report_progress(0.5, total=1.0, message="halfway")
+        return f"Hello, {name}!"
+
+    return mcp.streamable_http_app(json_response=True, transport_security=NO_DNS_REBIND)
+
+
+if __name__ == "__main__":
+    run_app_from_args(build_app)