diff --git a/doc/api/test.md b/doc/api/test.md
index 59b1647b12632a..310bf0d685ffe3 100644
--- a/doc/api/test.md
+++ b/doc/api/test.md
@@ -549,7 +549,7 @@ to the test runner's output is required, use the events emitted by the
 ### Custom reporters
 
 [`--test-reporter`][] can be used to specify a path to custom reporter.
-a custom reporter is a module that exports a value
+A custom reporter is a module that exports a value
 accepted by [stream.compose][].
 Reporters should transform events emitted by a {TestsStream}