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doc/api/ci/lint.md

 # Validate the .gitlab-ci.yml
+> [Introduced][ce-5953] in GitLab 8.12.
+
 Check whether your .gitlab-ci.yml file is valid.
 ```
@@ -11,35 +13,74 @@ POST ci/lint
 | `content`  | hash    | yes      | the .gitlab-ci.yaml content|
 ```bash
-curl --request POST "https://gitlab.example.com/api/v3/ci/lint?content=YAML+Content"
+curl --request POST "https://gitlab.example.com/api/v3/ci/lint?content={
+  image: "ruby:2.1",
+  services: ["postgres"],
+  before_script: ["gem install bundler", "bundle install", "bundle exec rake db:create"],
+  variables: {"DB_NAME": "postgres"},
+  types: ["test", "deploy", "notify"],
+  rspec: {
+    script: "rake spec",
+    tags: ["ruby", "postgres"],
+    only: ["branches"]
+  },
+  spinach: {
+    script: "rake spinach",
+    allow_failure: true,
+    tags: ["ruby", "mysql"],
+    except: ["tags"]
+  },
+  staging: {
+    variables: {KEY1: "value1", KEY2: "value2"},
+    script: "cap deploy stating",
+    type: "deploy",
+    tags: ["ruby", "mysql"],
+    except: ["stable"]
+  },
+  production: {
+    variables: {DB_NAME: "mysql"},
+    type: "deploy",
+    script: ["cap deploy production", "cap notify"],
+    tags: ["ruby", "mysql"],
+    only: ["master", "/^deploy-.*$/"]
+  },
+  dockerhub: {
+    type: "notify",
+    script: "curl http://dockerhub/URL",
+    tags: ["ruby", "postgres"],
+    only: ["branches"]
+  }
+}"
 ```
-Example response:
-* valid content
-```json
-{
-  "status": "valid",
-  "errors": []
-}
-```
-* invalid content
-```json
-{
-  "status": "invalid",
-  "errors": [
-    "variables config should be a hash of key value pairs"
-  ]
-}
-```
-* without the content attribute
-```json
-{
-  "error": "content is missing"
-}
-```
+Be sure to copy paste the exact contents of `.gitlab-ci.yml` as YAML is very picky with indentation and spaces.
+Example responses:
+* Valid content:
+    ```json
+    {
+      "status": "valid",
+      "errors": []
+    }
+    ```
+* Invalid content:
+    ```json
+    {
+      "status": "invalid",
+      "errors": [
+        "variables config should be a hash of key value pairs"
+      ]
+    }
+    ```
+* Without the content attribute:
+
+    ```json
+    {
+      "error": "content is missing"
+    }
+    ```