diff --git a/.travis.yml b/.travis.yml
index af7ead0..743014f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -15,6 +15,7 @@ jobs:
   include:
     - stage: test
       script:
+        - make test
         - make check
     - stage: test-doc
       script:
diff --git a/Makefile b/Makefile
index 9d46649..f8e4405 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,5 @@
+PYTHONPATH := $(shell pip show ansible | awk -F' ' '/Location/ {print $$2}')
+BASEDIR    := $(shell git rev-parse --show-toplevel)
 
 syntax:
 	pycodestyle --ignore=E265 library/grafana_annotations.py
@@ -5,5 +7,8 @@ syntax:
 container:
 	tools/start_grafana.sh
 
-check: container
+check: container 
 	GRAFANA_API_TOKEN='$(shell python tools/get_or_create_token.py)' ansible-playbook test.yml
+
+test:
+	PYTHONPATH=$(PYTHONPATH) BASEDIR=$(BASEDIR) pytest
diff --git a/library/grafana_annotations.py b/library/grafana_annotations.py
index 95d8120..9c62b88 100644
--- a/library/grafana_annotations.py
+++ b/library/grafana_annotations.py
@@ -215,8 +215,8 @@ def main():
     base_arg_spec = url_argument_spec()
     base_arg_spec.update(
         token=dict(required=False, default=None, no_log=True),
-        tstamp=dict(required=False, default=None),
-        end_tstamp=dict(required=False, default=None, type='int'),
+        time=dict(required=False, default=None),
+        timeEnd=dict(required=False, default=None, type='int'),
         tags=dict(required=False, default=[], type='list'),
         text=dict(required=True, type='str'),
     )
@@ -230,8 +230,8 @@ def main():
     url_username = module.params['url_username']
     url_password = module.params['url_password']
     token = module.params['token']
-    tstamp = module.params['tstamp']
-    end_tstamp = module.params['end_tstamp']
+    tstamp = module.params['time']
+    end_tstamp = module.params['timeEnd']
     tags = ["ansible"] + module.params['tags']
     text = module.params['text']
 
diff --git a/requirements.txt b/requirements.txt
index 54ece6a..2d03daf 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,3 @@
 ansible==2.6
 pycodestyle==2.3.1
+pytest==3.4.2
diff --git a/test.yml b/test.yml
index 0f0bf99..3fc2548 100644
--- a/test.yml
+++ b/test.yml
@@ -41,7 +41,7 @@
         url: "{{ grafana_url }}"
         url_username: "{{ grafana_login }}"
         url_password: "{{ grafana_password }}"
-        tstamp: "{{ curdate }}"
+        time: "{{ curdate }}"
         text: "This is an annotation explicitly set at {{ curdate }}"
         tags:
             - test-tag
@@ -59,7 +59,7 @@
         url: "{{ grafana_url }}"
         url_username: "{{ grafana_login }}"
         url_password: "{{ grafana_password }}"
-        tstamp: "{{ curdate }}"
+        time: "{{ curdate }}"
         text: "This is an annotation explicitly set at {{ curdate }}"
         tags:
             - test-tag
@@ -83,8 +83,8 @@
         url: "{{ grafana_url }}"
         url_username: "{{ grafana_login }}"
         url_password: "{{ grafana_password }}"
-        tstamp: "{{ start_date }}"
-        end_tstamp: "{{ end_date }}"
+        time: "{{ start_date }}"
+        timeEnd: "{{ end_date }}"
         text: "This is a global region annotation"
       register: anno
       tags:
@@ -100,8 +100,8 @@
         url: "{{ grafana_url }}"
         url_username: "{{ grafana_login }}"
         url_password: "{{ grafana_password }}"
-        tstamp: "{{ start_date }}"
-        end_tstamp: "{{ end_date }}"
+        time: "{{ start_date }}"
+        timeEnd: "{{ end_date }}"
         text: "This is a global region annotation"
       register: anno
       tags:
diff --git a/tests/test_base.py b/tests/test_base.py
new file mode 100644
index 0000000..bd62715
--- /dev/null
+++ b/tests/test_base.py
@@ -0,0 +1,77 @@
+import pytest
+import os
+import subprocess
+import json
+import time
+
+
+class TestClass(object):
+
+    # {{{ call module
+    def _run_module(self, json_args):
+        with open("/tmp/test.json", "w+") as jsonfile:
+            json.dump(json_args, jsonfile)
+        args = ["python", "%s/library/grafana_annotations.py" % os.getenv("BASEDIR"), "/tmp/test.json"]
+        p = subprocess.Popen(args, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        p.wait()
+        return p.returncode, p.stdout.read(), p.stderr.read()
+    # }}}
+
+    def test_basic(self):
+        module_args = {
+            "ANSIBLE_MODULE_ARGS": {
+                "text": "This is pytest basic test without time value",
+                "url": "http://127.0.0.1:3000/api/annotations",
+                "url_password": "admin",
+                "url_username": "admin",
+                "_ansible_remote_tmp": "/tmp",
+                "_ansible_keep_remote_files": "false"
+            }
+        }
+        rc, stdout, stderr = self._run_module(module_args)
+        assert rc == 0, stderr
+        ouput_json = json.loads(stdout)
+        assert ouput_json.get("changed") is True
+
+    def test_explicit_time(self):
+        current_time = int(time.time())
+        module_args = {
+            "ANSIBLE_MODULE_ARGS": {
+                "text": "This is pytest basic test with explicit time value",
+                "url": "http://127.0.0.1:3000/api/annotations",
+                "url_password": "admin",
+                "url_username": "admin",
+                "time": str(current_time),
+                "_ansible_remote_tmp": "/tmp",
+                "_ansible_keep_remote_files": "false"
+            }
+        }
+        rc, stdout, stderr = self._run_module(module_args)
+        assert rc == 0, stderr
+        ouput_json = json.loads(stdout)
+        assert ouput_json.get("changed") is True, ouput_json
+
+    def test_idempotency(self):
+        current_time = int(time.time())
+        module_args = {
+            "ANSIBLE_MODULE_ARGS": {
+                "text": "This is pytest basic test for idempotency",
+                "url": "http://127.0.0.1:3000/api/annotations",
+                "url_password": "admin",
+                "url_username": "admin",
+                "time": str(current_time),
+                "_ansible_remote_tmp": "/tmp",
+                "_ansible_keep_remote_files": "false"
+            }
+        }
+        # {{{ send the annotation once
+        rc, stdout, stderr = self._run_module(module_args)
+        assert rc == 0, stderr
+        ouput_json = json.loads(stdout)
+        assert ouput_json.get("changed") is True, ouput_json
+        # }}}
+        # send the annotation again
+        rc, stdout, stderr = self._run_module(module_args)
+        assert rc == 0, stderr
+        ouput_json = json.loads(stdout)
+        assert ouput_json.get("changed") is False, ouput_json