diff --git a/trace-utils/Cargo.toml b/trace-utils/Cargo.toml
index cb69a4271..4ef27bebf 100644
--- a/trace-utils/Cargo.toml
+++ b/trace-utils/Cargo.toml
@@ -23,6 +23,7 @@ datadog-trace-normalization = { path = "../trace-normalization" }
 tokio = { version = "1", features = ["macros", "rt-multi-thread"] }
 rand = "0.8.5"
 bytes = "1.6.0"
+# This should only be used for testing. It isn't under dev-dependencies because test-utils can't be under #[cfg(test)].
 httpmock = { version = "0.7.0", optional = true}
 
 [dev-dependencies]