diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index 28a2e6a5750..614d95b022c 100644
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@@ -1209,7 +1209,7 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 		OPT_CMDMODE(0, "bisect-visualize", &cmdmode,
 			 N_("visualize the bisection"), BISECT_VISUALIZE),
 		OPT_CMDMODE(0, "bisect-run", &cmdmode,
-			 N_("use <cmd>... to automatically bisect."), BISECT_RUN),
+			 N_("use <cmd>... to automatically bisect"), BISECT_RUN),
 		OPT_BOOL(0, "no-log", &nolog,
 			 N_("no log for BISECT_WRITE")),
 		OPT_END()
diff --git a/builtin/reflog.c b/builtin/reflog.c
index 85b838720c3..28372c5e2b5 100644
--- a/builtin/reflog.c
+++ b/builtin/reflog.c
@@ -600,7 +600,7 @@ static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 		OPT_BIT(0, "updateref", &flags,
 			N_("update the reference to the value of the top reflog entry"),
 			EXPIRE_REFLOGS_UPDATE_REF),
-		OPT_BOOL(0, "verbose", &verbose, N_("print extra information on screen.")),
+		OPT_BOOL(0, "verbose", &verbose, N_("print extra information on screen")),
 		OPT_CALLBACK_F(0, "expire", &cmd, N_("timestamp"),
 			       N_("prune entries older than the specified time"),
 			       PARSE_OPT_NONEG,
@@ -613,7 +613,7 @@ static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 			 N_("prune any reflog entries that point to broken commits")),
 		OPT_BOOL(0, "all", &do_all, N_("process the reflogs of all references")),
 		OPT_BOOL(1, "single-worktree", &all_worktrees,
-			 N_("limits processing to reflogs from the current worktree only.")),
+			 N_("limits processing to reflogs from the current worktree only")),
 		OPT_END()
 	};
 
@@ -736,7 +736,7 @@ static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
 		OPT_BIT(0, "updateref", &flags,
 			N_("update the reference to the value of the top reflog entry"),
 			EXPIRE_REFLOGS_UPDATE_REF),
-		OPT_BOOL(0, "verbose", &verbose, N_("print extra information on screen.")),
+		OPT_BOOL(0, "verbose", &verbose, N_("print extra information on screen")),
 		OPT_END()
 	};
 
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 33c82c3ab91..6332d305983 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -1875,7 +1875,7 @@ static int module_clone(int argc, const char **argv, const char *prefix)
 		OPT_STRING(0, "depth", &clone_data.depth,
 			   N_("string"),
 			   N_("depth for shallow clones")),
-		OPT__QUIET(&quiet, "Suppress output for cloning a submodule"),
+		OPT__QUIET(&quiet, "suppress output for cloning a submodule"),
 		OPT_BOOL(0, "progress", &progress,
 			   N_("force cloning progress")),
 		OPT_BOOL(0, "require-init", &require_init,
diff --git a/diff.c b/diff.c
index 7d5cfd325ea..387435a4a45 100644
--- a/diff.c
+++ b/diff.c
@@ -5630,7 +5630,7 @@ static void prep_parse_options(struct diff_options *options)
 			       N_("select files by diff type"),
 			       PARSE_OPT_NONEG, diff_opt_diff_filter),
 		{ OPTION_CALLBACK, 0, "output", options, N_("<file>"),
-		  N_("Output to a specific file"),
+		  N_("output to a specific file"),
 		  PARSE_OPT_NONEG, NULL, 0, diff_opt_output },
 
 		OPT_END()
diff --git a/parse-options.c b/parse-options.c
index 2437ad3bcdd..91cbfb0d7f7 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -492,6 +492,15 @@ static void parse_options_check(const struct option *opts)
 		default:
 			; /* ok. (usually accepts an argument) */
 		}
+		if (opts->type != OPTION_GROUP && opts->help &&
+			!(starts_with(opts->help, "HEAD") ||
+			  starts_with(opts->help, "GPG") ||
+			  starts_with(opts->help, "DEPRECATED") ||
+			  starts_with(opts->help, "SHA1")) &&
+			  (opts->help[0] >= 65 && opts->help[0] <= 90))
+			err |= optbug(opts, xstrfmt("help should not start with capital letter unless needed: %s", opts->help));
+		if (opts->help && !ends_with(opts->help, "...") && ends_with(opts->help, "."))
+			err |= optbug(opts, xstrfmt("help should not end with a dot: %s", opts->help));
 		if (opts->argh &&
 		    strcspn(opts->argh, " _") != strlen(opts->argh))
 			err |= optbug(opts, "multi-word argh should use dash to separate words");
diff --git a/t/helper/test-run-command.c b/t/helper/test-run-command.c
index 913775a14b7..8f370cd89f1 100644
--- a/t/helper/test-run-command.c
+++ b/t/helper/test-run-command.c
@@ -221,9 +221,9 @@ static int quote_stress_test(int argc, const char **argv)
 	struct strbuf out = STRBUF_INIT;
 	struct strvec args = STRVEC_INIT;
 	struct option options[] = {
-		OPT_INTEGER('n', "trials", &trials, "Number of trials"),
-		OPT_INTEGER('s', "skip", &skip, "Skip <n> trials"),
-		OPT_BOOL('m', "msys2", &msys2, "Test quoting for MSYS2's sh"),
+		OPT_INTEGER('n', "trials", &trials, "number of trials"),
+		OPT_INTEGER('s', "skip", &skip, "skip <n> trials"),
+		OPT_BOOL('m', "msys2", &msys2, "test quoting for MSYS2's sh"),
 		OPT_END()
 	};
 	const char * const usage[] = {
diff --git a/t/t1502-rev-parse-parseopt.sh b/t/t1502-rev-parse-parseopt.sh
index 284fe18e726..2a07e130b96 100755
--- a/t/t1502-rev-parse-parseopt.sh
+++ b/t/t1502-rev-parse-parseopt.sh
@@ -53,7 +53,7 @@ test_expect_success 'setup optionspec-only-hidden-switches' '
 |
 |some-command does foo and bar!
 |--
-|hidden1* A hidden switch
+|hidden1* a hidden switch
 EOF
 '
 
@@ -131,7 +131,7 @@ test_expect_success 'test --parseopt help-all output hidden switches' '
 |
 |    some-command does foo and bar!
 |
-|    --hidden1             A hidden switch
+|    --hidden1             a hidden switch
 |
 |EOF
 END_EXPECT
