diff --git a/CHANGELOG b/CHANGELOG
index 2af2056979d..bf1136afd03 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -92,6 +92,7 @@ v 8.12.0 (unreleased)
   - Refactor the triggers page and documentation !6217
   - Show values of CI trigger variables only when clicked (Katarzyna Kobierska Ula Budziszewska)
   - Use default clone protocol on "check out, review, and merge locally" help page URL
+  - API for Ci Lint !5953 (Katarzyna Kobierska Urszula Budziszewska)
 
 v 8.11.5 (unreleased)
   - Optimize branch lookups and force a repository reload for Repository#find_branch
diff --git a/app/controllers/ci/lints_controller.rb b/app/controllers/ci/lints_controller.rb
index 67028b66a66..e03543a9267 100644
--- a/app/controllers/ci/lints_controller.rb
+++ b/app/controllers/ci/lints_controller.rb
@@ -11,9 +11,9 @@ module Ci
       if @content.blank?
         @status = false
         @error = "Please provide content of .gitlab-ci.yml"
-      elsif Ci::GitlabCiYamlProcessor.validate(@content) != "valid"
+      elsif Ci::GitlabCiYamlProcessor.errors(@content) != nil
         @status = false
-        @error = Ci::GitlabCiYamlProcessor.validate(@content)
+        @error = Ci::GitlabCiYamlProcessor.errors(@content)
       else
         @config_processor = Ci::GitlabCiYamlProcessor.new(@content)
         @stages = @config_processor.stages
diff --git a/lib/api/lint.rb b/lib/api/lint.rb
index 2d27bc65462..379c266abe1 100644
--- a/lib/api/lint.rb
+++ b/lib/api/lint.rb
@@ -2,7 +2,7 @@ module API
   class Lint < Grape::API
     resource :lint do
       params do
-        requires :content, type: String, desc: 'content of .gitlab-ci.yml'
+        requires :content, type: String, desc: 'Content of .gitlab-ci.yml'
       end
 
       desc 'Validation of .gitlab-ci.yml content'
@@ -13,9 +13,9 @@ module API
           jobs: []
         }
 
-        if Ci::GitlabCiYamlProcessor.validate(@content) != "valid"
+        if Ci::GitlabCiYamlProcessor.errors(@content) != nil
           status 200
-          response[:errors].push(e.message)
+          response[:errors].push(Ci::GitlabCiYamlProcessor.errors(@content))
           response[:status] = 'invalid'
 
           response
diff --git a/lib/ci/gitlab_ci_yaml_processor.rb b/lib/ci/gitlab_ci_yaml_processor.rb
index 9799f494df6..40c84b93799 100644
--- a/lib/ci/gitlab_ci_yaml_processor.rb
+++ b/lib/ci/gitlab_ci_yaml_processor.rb
@@ -78,10 +78,10 @@ module Ci
       }
     end
 
-    def self.validate(content)
+    def self.errors(content)
       begin
         Ci::GitlabCiYamlProcessor.new(content)
-        "valid"
+        nil
       rescue ValidationError, Psych::SyntaxError => e
         e.message
       end
diff --git a/spec/lib/ci/gitlab_ci_yaml_processor_spec.rb b/spec/lib/ci/gitlab_ci_yaml_processor_spec.rb
index bd5ea2bb97d..0125f149581 100644
--- a/spec/lib/ci/gitlab_ci_yaml_processor_spec.rb
+++ b/spec/lib/ci/gitlab_ci_yaml_processor_spec.rb
@@ -1251,21 +1251,21 @@ EOT
       end
     end
 
-    describe "#validate(config)" do
+    describe "#errors(content)" do
       describe "Error handling" do
-        it "returns error to parse YAML" do
-          config = YAML.dump("invalid: yaml: test")
-          expect(GitlabCiYamlProcessor.validate(config)).to eq "Invalid configuration format"
+        it "returns error if parse YAML failed" do
+          content = YAML.dump("invalid: yaml: test")
+          expect(GitlabCiYamlProcessor.errors(content)).to eq "Invalid configuration format"
         end
 
         it "returns errors if tags parameter is invalid" do
-          config = YAML.dump({ rspec: { script: "test", tags: "mysql" } })
-          expect(GitlabCiYamlProcessor.validate(config)).to eq "jobs:rspec tags should be an array of strings"
+          content = YAML.dump({ rspec: { script: "test", tags: "mysql" } })
+          expect(GitlabCiYamlProcessor.errors(content)).to eq "jobs:rspec tags should be an array of strings"
         end
 
         it "does not return errors" do
-          config = File.read(Rails.root.join('spec/support/gitlab_stubs/gitlab_ci.yml'))
-          expect(GitlabCiYamlProcessor.validate(config)).to eq "valid"
+          content = File.read(Rails.root.join('spec/support/gitlab_stubs/gitlab_ci.yml'))
+          expect(GitlabCiYamlProcessor.errors(content)).to eq nil
         end
       end
     end