diff --git a/docs/comparator.md b/docs/comparator.md
deleted file mode 100644
index 74a7673f..00000000
--- a/docs/comparator.md
+++ /dev/null
@@ -1,22 +0,0 @@
-# Comparator
-
-| comparator | Description | A(check), B(expected) | examples |
-|:------------:|-----------|------------------------------------|-----------|
-| `eq`, `==` | value is equal | A == B | 9 eq 9 |
-| `lt` | less than | A < B | 7 lt 8 |
-| `le` | less than or equals | A <= B | 7 le 8, 8 le 8 |
-| `gt` | greater than | A > B | 8 gt 7 |
-| `ge` | greater than or equals | A >= B | 8 ge 7, 8 ge 8 |
-| `ne` | not equals | A != B | 6 ne 9 |
-| `str_eq` | string equals | str(A) == str(B) | 123 str_eq '123' |
-| `len_eq`, `count_eq` | length or count equals | len(A) == B | 'abc' len_eq 3<br/>[1,2] len_eq 2 |
-| `len_gt`, `count_gt` | length greater than | len(A) > B | 'abc' len_gt 2<br/>[1,2,3] len_gt 2 |
-| `len_ge`, `count_ge` | length greater than or equals | len(A) >= B | 'abc' len_ge 3<br/>[1,2,3] len_gt 3 |
-| `len_lt`, `count_lt` | length less than | len(A) < B | 'abc' len_lt 4<br/>[1,2,3] len_lt 4 |
-| `len_le`, `count_le` | length less than or equals | len(A) <= B | 'abc' len_le 3<br/>[1,2,3] len_le 3 |
-| `contains` | contains | B in A | [1, 2] contains 1<br/>'abc' contains 'a' |
-| `contained_by` | contained by | A in B | 1 contained_by [1,2]<br/>'a' contained_by 'abc' |
-| `type` | type of A is instance of B | isinstance(A, B) | 123 type 'int' |
-| `regex` | regex matches | re.match(B, A) | 'abcdef' regex 'a\w+d' |
-| `startswith` | starts with | A.startswith(B) is True | 'abc' startswith 'ab' |
-| `endswith` | ends with | A.endswith(B) is True | 'abc' endswith 'bc' |
diff --git a/docs/extraction-and-validation.md b/docs/extraction-and-validation.md
deleted file mode 100644
index 0e380f3c..00000000
--- a/docs/extraction-and-validation.md
+++ /dev/null
@@ -1,58 +0,0 @@
-# Extraction and Validation
-
-Suppose we get the following HTTP response.
-
-```text
-# status code: 200
-
-# response headers
-{
-    "Content-Type": "application/json"
-}
-
-# response body content
-{
-    "success": False,
-    "person": {
-        "name": {
-            "first_name": "Leo",
-            "last_name": "Lee",
-        },
-        "age": 29,
-        "cities": ["Guangzhou", "Shenzhen"]
-    }
-}
-```
-
-In `extract` and `validate`, we can do chain operation to extract data field in HTTP response.
-
-For instance, if we want to get `Content-Type` in response headers, then we can specify `headers.content-type`; if we want to get `first_name` in response content, we can specify `content.person.name.first_name`.
-
-There might be slight difference on list, cos we can use index to locate list item. For example, `Guangzhou` in response content can be specified by `content.person.cities.0`.
-
-```text
-# get status code
-status_code
-
-# get headers field
-headers.content-type
-
-# get content field
-body.success
-content.success
-text.success
-content.person.name.first_name
-content.person.cities.1
-```
-
-```yaml
-extract:
-    - content_type: headers.content-type
-    - first_name: content.person.name.first_name
-validate:
-    - {"check": "status_code", "comparator": "eq", "expected": 200}
-    - {"check": "headers.content-type", "expected": "application/json"}
-    - {"check": "headers.content-length", "comparator": "gt", "expected": 40}
-    - {"check": "content.success", "comparator": "eq", "expected": True}
-    - {"check": "content.token", "comparator": "len_eq", "expected": 16}
-```
diff --git a/examples/quickstart-demo-rev-3.yml b/examples/quickstart-demo-rev-3.yml
index 7038d8e6..f50f5908 100644
--- a/examples/quickstart-demo-rev-3.yml
+++ b/examples/quickstart-demo-rev-3.yml
@@ -25,6 +25,8 @@
     extract:
         - token: content.token
     validate:
+        - eq: ["status_code", 200]
+        - len_eq: ["content.token", 16]
         - {"check": "status_code", "comparator": "eq", "expect": 200}
         - {"check": "content.token", "comparator": "len_eq", "expect": 16}
 
diff --git a/httprunner/runner.py b/httprunner/runner.py
index 86203631..628d5082 100644
--- a/httprunner/runner.py
+++ b/httprunner/runner.py
@@ -72,7 +72,7 @@ class Runner(object):
         @param (dict) testcase_dict
             {
                 "name": "testcase description",
-                "skip": Fasle,
+                "skip": "skip this test unconditionally",
                 "times": 3,
                 "requires": [],         # optional, override
                 "function_binds": {},   # optional, override
@@ -87,7 +87,7 @@ class Runner(object):
                     },
                     "body": '{"name": "user", "password": "123456"}'
                 },
-                "extract": [], # optional
+                "extract": [],       # optional
                 "validate": [],      # optional
                 "setup": [],         # optional
                 "teardown": []       # optional