diff --git a/tools/codegen/core/gen_load_balancing_proto.sh b/tools/codegen/core/gen_nano_proto.sh
similarity index 78%
rename from tools/codegen/core/gen_load_balancing_proto.sh
rename to tools/codegen/core/gen_nano_proto.sh
index 339da0a..e2d2f67 100755
--- a/tools/codegen/core/gen_load_balancing_proto.sh
+++ b/tools/codegen/core/gen_nano_proto.sh
@@ -31,8 +31,16 @@
 
 #
 # Example usage:
-#   tools/codegen/core/gen_load_balancing_proto.sh \
+#   tools/codegen/core/gen_nano_proto.sh \
 #     src/proto/grpc/lb/v0/load_balancer.proto
+#     $PWD/src/core/ext/lb_policy/grpclb/proto/grpc/lb/v0
+#
+# Exit statuses:
+# 1: Incorrect number of arguments
+# 2: Input proto file (1st argument) doesn't exist or is not a regular file.
+# 3: Options file for nanopb not found in same dir as the input proto file.
+# 4: Output dir not an absolute path.
+# 5: Couldn't create output directory (2nd argument).
 
 read -r -d '' COPYRIGHT <<'EOF'
 /*
@@ -75,34 +83,37 @@
 echo "${COPYRIGHT/<YEAR>/$CURRENT_YEAR}" > $COPYRIGHT_FILE
 
 set -ex
-if [ $# -eq 0 ]; then
-  echo "Usage: $0 <load_balancer.proto> [output dir]"
+if [ $# -lt 2 ] || [ $# -gt 3 ]; then
+  echo "Usage: $0 <input.proto> <absolute path to output dir> [grpc path]"
   exit 1
 fi
 
-readonly GRPC_ROOT=$PWD
-
-OUTPUT_DIR="$GRPC_ROOT/src/core/ext/lb_policy/grpclb/proto/grpc/lb/v0"
-if [ $# -eq 2 ]; then
-  mkdir -p "$2"
-  if [ $? != 0 ]; then
-    echo "Error creating output directory $2"
-    exit 2
-  fi
-  OUTPUT_DIR="$2"
-fi
-
+readonly GRPC_ROOT="$PWD"
+readonly INPUT_PROTO="$1"
+readonly OUTPUT_DIR="$2"
+readonly GRPC_OUTPUT_DIR="${3:-$OUTPUT_DIR}"
 readonly EXPECTED_OPTIONS_FILE_PATH="${1%.*}.options"
 
-if [[ ! -f "$1" ]]; then
-  echo "Input proto file '$1' doesn't exist."
-  exit 3
+if [[ ! -f "$INPUT_PROTO" ]]; then
+  echo "Input proto file '$INPUT_PROTO' doesn't exist."
+  exit 2
 fi
 if [[ ! -f "${EXPECTED_OPTIONS_FILE_PATH}" ]]; then
   echo "Expected nanopb options file '${EXPECTED_OPTIONS_FILE_PATH}' missing"
+  exit 3
+fi
+
+if [[ "${OUTPUT_DIR:0:1}" != '/' ]]; then
+  echo "The output directory must be an absolute path. Got '$OUTPUT_DIR'"
   exit 4
 fi
 
+mkdir -p "$OUTPUT_DIR"
+if [ $? != 0 ]; then
+  echo "Error creating output directory $OUTPUT_DIR"
+  exit 5
+fi
+
 readonly VENV_DIR=$(mktemp -d)
 readonly VENV_NAME="nanopb-$(date '+%Y%m%d_%H%M%S_%N')"
 pushd $VENV_DIR
@@ -114,16 +125,16 @@
 # ideally we'd update this as a template to ensure that
 pip install protobuf==3.0.0b2
 
-pushd "$(dirname $1)" > /dev/null
+pushd "$(dirname $INPUT_PROTO)" > /dev/null
 
 protoc \
 --plugin=protoc-gen-nanopb="$GRPC_ROOT/third_party/nanopb/generator/protoc-gen-nanopb" \
 --nanopb_out='-T -L#include\ \"third_party/nanopb/pb.h\"'":$OUTPUT_DIR" \
-"$(basename $1)"
+"$(basename $INPUT_PROTO)"
 
-readonly PROTO_BASENAME=$(basename $1 .proto)
-sed -i "s:$PROTO_BASENAME.pb.h:src/core/ext/lb_policy/grpclb/proto/grpc/lb/v0/$PROTO_BASENAME.pb.h:g" \
-    "$OUTPUT_DIR/$PROTO_BASENAME.pb.c"
+readonly PROTO_BASENAME=$(basename $INPUT_PROTO .proto)
+sed -i "s:$PROTO_BASENAME.pb.h:${GRPC_OUTPUT_DIR}/$PROTO_BASENAME.pb.h:g" \
+  "$OUTPUT_DIR/$PROTO_BASENAME.pb.c"
 
 # prepend copyright
 TMPFILE=$(mktemp)
diff --git a/tools/distrib/check_nanopb_output.sh b/tools/distrib/check_nanopb_output.sh
index 4f68e4c..92cb8ec 100755
--- a/tools/distrib/check_nanopb_output.sh
+++ b/tools/distrib/check_nanopb_output.sh
@@ -31,36 +31,42 @@
 set -ex
 
 readonly NANOPB_TMP_OUTPUT="$(mktemp -d)"
+readonly PROTOBUF_INSTALL_PREFIX="$(mktemp -d)"
 
 # install protoc version 3
 pushd third_party/protobuf
 ./autogen.sh
-./configure
+./configure --prefix="$PROTOBUF_INSTALL_PREFIX"
 make
 make install
-ldconfig
+#ldconfig
 popd
 
-if [ ! -x "/usr/local/bin/protoc" ]; then
-  echo "Error: protoc not found in path"
+readonly PROTOC_BIN_PATH="$PROTOBUF_INSTALL_PREFIX/bin"
+if [ ! -x "$PROTOBUF_INSTALL_PREFIX/bin/protoc" ]; then
+  echo "Error: protoc not found in temp install dir '$PROTOBUF_INSTALL_PREFIX'"
   exit 1
 fi
-readonly PROTOC_PATH='/usr/local/bin'
+
 # stack up and change to nanopb's proto generator directory
 pushd third_party/nanopb/generator/proto
-PATH="$PROTOC_PATH:$PATH" make
-
+export PATH="$PROTOC_BIN_PATH:$PATH"
+make
 # back to the root directory
 popd
 
-
+#
+# Checks for load_balancer.proto
+#
+readonly LOAD_BALANCER_GRPC_OUTPUT_PATH='src/core/ext/lb_policy/grpclb/proto/grpc/lb/v0'
 # nanopb-compile the proto to a temp location
-PATH="$PROTOC_PATH:$PATH" ./tools/codegen/core/gen_load_balancing_proto.sh \
+./tools/codegen/core/gen_nano_proto.sh \
   src/proto/grpc/lb/v0/load_balancer.proto \
-  $NANOPB_TMP_OUTPUT
+  "$NANOPB_TMP_OUTPUT" \
+  "$LOAD_BALANCER_GRPC_OUTPUT_PATH"
 
 # compare outputs to checked compiled code
 if ! diff -r $NANOPB_TMP_OUTPUT src/core/ext/lb_policy/grpclb/proto/grpc/lb/v0; then
-  echo "Outputs differ: $NANOPB_TMP_OUTPUT vs src/core/ext/lb_policy/grpclb/proto/grpc/lb/v0"
+  echo "Outputs differ: $NANOPB_TMP_OUTPUT vs $LOAD_BALANCER_GRPC_OUTPUT_PATH"
   exit 2
 fi