diff --git a/server/src/middleware/correlationId.ts b/server/src/middleware/correlationId.ts
index d3e63c044..2751ecd87 100644
--- a/server/src/middleware/correlationId.ts
+++ b/server/src/middleware/correlationId.ts
@@ -1,3 +1,6 @@
+// TODO(#1322): add test coverage proving the propagation rules documented
+// below (inbound X-Correlation-ID honored when valid, fresh UUID otherwise,
+// X-Request-ID always regenerated per hop, both echoed in response headers).
 import { NextFunction, Request, Response } from "express";
 import crypto from "crypto";