diff --git a/tools/callgrind.c b/tools/callgrind.c
index 35ae142..f52b2d9 100644
--- a/tools/callgrind.c
+++ b/tools/callgrind.c
@@ -26,10 +26,24 @@ extern KrkValue krk_operator_add (KrkValue a, KrkValue b);
 extern KrkValue krk_operator_sub (KrkValue a, KrkValue b);
 
 static int usage(char * argv[]) {
-	fprintf(stderr, "usage: %s [FILE] [args...]\n", argv[0]);
+	fprintf(stderr, "usage: %s [-f LOG_FILE] [-q] FILE [args...]\n", argv[0]);
 	return 1;
 }
 
+static int help(char * argv[]) {
+	usage(argv);
+	fprintf(stderr,
+		"Generate callgrind-format trace files.\n"
+		"\n"
+		"Options:\n"
+		" -f LOG_FILE Output callgrind-format data to LOG_FILE.\n"
+		" -q          Do not print execution summary.\n"
+		"\n"
+		" --help      Show this help text.\n"
+		"\n");
+	return 0;
+}
+
 static KrkValue lineCache; /* {sourceCO: {line: count}} */
 static KrkValue callCache; /* {sourceCO: {(codeobject,targetLine,sourceLine): [calls,instructions,time]}} */
 static KrkValue timeCache; /* {sourceCO: time} */
@@ -37,6 +51,7 @@ static KrkValue timeCache; /* {sourceCO: time} */
 static size_t lastFrameCount = 0;   /* Previously seen frame count, to track function entry/exit */
 static size_t instrCounter = 0;     /* Total counter of executed instructions */
 static size_t functionsEntered = 0; /* Number of function entries seen */
+static int    quiet = 0;
 
 /**
  * @brief Calculate time difference as string.
@@ -203,11 +218,14 @@ int main(int argc, char *argv[]) {
 	snprintf(outfile,1024,"callgrind.out.%d",getpid());
 
 	int opt;
-	while ((opt = getopt(argc, argv, "+:f:-:")) != -1) {
+	while ((opt = getopt(argc, argv, "+:f:q-:")) != -1) {
 		switch (opt) {
 			case 'f':
 				snprintf(outfile,1024,"%s", optarg);
 				break;
+			case 'q':
+				quiet = 1;
+				break;
 			case '?':
 				if (optopt != '-') {
 					fprintf(stderr, "%s: unrocognized option '%c'\n", argv[0], optopt);
@@ -217,6 +235,7 @@ int main(int argc, char *argv[]) {
 				/* fall through */
 			case '-':
 				if (!strcmp(optarg,"help")) {
+					return help(argv);
 				} else {
 					fprintf(stderr, "%s: unrecognized option: '--%s'\n", argv[0], optarg);
 					return 1;
@@ -245,14 +264,16 @@ int main(int argc, char *argv[]) {
 
 	if (krk_currentThread.flags & KRK_THREAD_HAS_EXCEPTION) {
 		krk_currentThread.flags &= ~(KRK_THREAD_HAS_EXCEPTION);
-		fprintf(stderr, "== Executed ended by exception ==\n");
+		if (!quiet) fprintf(stderr, "== Executed ended by exception ==\n");
 	} else {
-		fprintf(stderr, "== Execution completed ==\n");
+		if (!quiet) fprintf(stderr, "== Execution completed ==\n");
 	}
 	krk_callgrind_debuggerHook(NULL);
 
-	fprintf(stderr, "%10zu total instruction%s\n", instrCounter, (instrCounter != 1) ? "s" : "");
-	fprintf(stderr, "%10zu function%s calls\n", functionsEntered, (functionsEntered != 1) ? "s" : "");
+	if (!quiet) {
+		fprintf(stderr, "%10zu total instruction%s\n", instrCounter, (instrCounter != 1) ? "s" : "");
+		fprintf(stderr, "%10zu function%s calls\n", functionsEntered, (functionsEntered != 1) ? "s" : "");
+	}
 
 	FILE * f = fopen(outfile,"w");
 	if (!f) {
diff --git a/tools/watchdog.c b/tools/watchdog.c
index a29c15c..b07e3dd 100644
--- a/tools/watchdog.c
+++ b/tools/watchdog.c
@@ -9,13 +9,35 @@
 
 #include "common.h"
 
+#define DEFAULT_LIMIT 500000
+
 static int usage(char * argv[]) {
-	fprintf(stderr, "usage: %s [-s count] [FILE] [args...]\n", argv[0]);
+	fprintf(stderr, "usage: %s [-s COUNT] [-q] FILE [args...]\n", argv[0]);
 	return 1;
 }
 
+static int help(char * argv[]) {
+	usage(argv);
+	fprintf(stderr,
+		"Run scripts with an instruction counter and halt when a "
+		"limit is exceeded. The default limit is %d. A total count of "
+		"executed instructions is printed after completion.\n"
+		"\n"
+		"Options:\n"
+		" -s COUNT    Set watchdog timeout to COUNT instructions.\n"
+		"             Specify -1 to set disable limit.\n"
+		" -q          Do not print total instruction count.\n"
+		"\n"
+		" --help      Show this help text.\n"
+		"\n",
+		DEFAULT_LIMIT);
+	return 0;
+}
+
+
 static size_t instrCounter = 0;     /* Total counter of executed instructions */
-static size_t stopAt = 500000;
+static size_t stopAt = DEFAULT_LIMIT;
+static int    quiet = 0;
 
 int krk_callgrind_debuggerHook(KrkCallFrame * frame) {
 	instrCounter++;
@@ -29,11 +51,14 @@ int krk_callgrind_debuggerHook(KrkCallFrame * frame) {
 
 int main(int argc, char *argv[]) {
 	int opt;
-	while ((opt = getopt(argc, argv, "+:s:-:")) != -1) {
+	while ((opt = getopt(argc, argv, "+:s:q-:")) != -1) {
 		switch (opt) {
 			case 's':
 				stopAt = strtoul(optarg,NULL,10);
 				break;
+			case 'q':
+				quiet = 1;
+				break;
 			case '?':
 				if (optopt != '-') {
 					fprintf(stderr, "%s: unrocognized option '%c'\n", argv[0], optopt);
@@ -43,6 +68,7 @@ int main(int argc, char *argv[]) {
 				/* fall through */
 			case '-':
 				if (!strcmp(optarg,"help")) {
+					return help(argv);
 				} else {
 					fprintf(stderr, "%s: unrecognized option: '--%s'\n", argv[0], optarg);
 					return 1;
@@ -62,7 +88,9 @@ int main(int argc, char *argv[]) {
 	krk_startModule("__main__");
 	krk_runfile(argv[optind],argv[optind]);
 
-	fprintf(stderr, "%zu total instructions\n", instrCounter);
+	if (!quiet) {
+		fprintf(stderr, "%zu total instructions\n", instrCounter);
+	}
 
 	krk_freeVM();
 	return 0;