diff --git a/packages/apidom-ls/src/config/codes.ts b/packages/apidom-ls/src/config/codes.ts
index 0ce246d7c3..fbaad4db32 100644
--- a/packages/apidom-ls/src/config/codes.ts
+++ b/packages/apidom-ls/src/config/codes.ts
@@ -717,6 +717,7 @@ enum ApilintCodes {
   OPENAPI2_PARAMETER_FIELD_IN_EQUALS = 3100200,
   OPENAPI2_PARAMETER_FIELD_IN_REQUIRED,
   OPENAPI2_PARAMETER_FIELD_IN_VALID,
+  OPENAPI2_PARAMETER_FIELD_IN_MULTIPLE_BODY,
   OPENAPI2_PARAMETER_FIELD_DESCRIPTION_TYPE = 3100300,
   OPENAPI2_PARAMETER_FIELD_REQUIRED_TYPE = 3100400,
   OPENAPI2_PARAMETER_FIELD_REQUIRED_REQUIRED,
@@ -740,6 +741,7 @@ enum ApilintCodes {
   OPENAPI2_PARAMETER_FIELD_ENUM_TYPE = 3101800,
   OPENAPI2_PARAMETER_FIELD_MULTIPLE_OF_TYPE = 3101900,
   OPENAPI2_PARAMETER_FIELD_IN_PATH_TEMPLATE = 3102000,
+  OPENAPI2_PARAMETER_FIELD_NAME_UNIQUE = 3103000,
 
   OPENAPI2_ITEMS = 3110000,
   OPENAPI2_ITEMS_FIELD_TYPE_EQUALS = 3110100,
@@ -976,6 +978,8 @@ enum ApilintCodes {
   OPENAPI3_0_PARAMETER_FIELD_IN_TYPE = 5150300,
   OPENAPI3_0_PARAMETER_FIELD_IN_REQUIRED,
   OPENAPI3_0_PARAMETER_FIELD_IN_EQUALS,
+  OPENAPI3_0_PARAMETER_FIELD_IN_AUTHORIZATION,
+  OPENAPI3_0_PARAMETER_FIELD_IN_CONTENT_TYPE,
   OPENAPI3_0_PARAMETER_FIELD_DESCRIPTION_TYPE = 5150400,
   OPENAPI3_0_PARAMETER_FIELD_REQUIRED_TYPE = 5150500,
   OPENAPI3_0_PARAMETER_FIELD_REQUIRED_REQUIRED,
diff --git a/packages/apidom-ls/src/config/openapi/parameter/lint/in--accept.ts b/packages/apidom-ls/src/config/openapi/parameter/lint/in--accept.ts
new file mode 100644
index 0000000000..f435f9eccd
--- /dev/null
+++ b/packages/apidom-ls/src/config/openapi/parameter/lint/in--accept.ts
@@ -0,0 +1,31 @@
+import { DiagnosticSeverity } from 'vscode-languageserver-types';
+
+import { OpenAPI3 } from '../../target-specs.ts';
+import ApilintCodes from '../../../codes.ts';
+
+const inAcceptLint = {
+  code: ApilintCodes.OPENAPI3_0_PARAMETER_FIELD_IN_CONTENT_TYPE,
+  source: 'apilint',
+  message:
+    'Header Parameter named "Accept" is ignored. The values for the "Accept" header are defined by `requestBody.content.<media-type>`',
+  severity: DiagnosticSeverity.Warning,
+  linterParams: ['^(?!\\b(A|a)ccept\\b).*$'],
+  linterFunction: 'apilintValueRegex',
+  marker: 'value',
+  target: 'name',
+  data: {},
+  conditions: [
+    {
+      targets: [
+        {
+          path: 'in',
+        },
+      ],
+      function: 'apilintContainsValue',
+      params: ['header'],
+    },
+  ],
+  targetSpecs: OpenAPI3,
+};
+
+export default inAcceptLint;
diff --git a/packages/apidom-ls/src/config/openapi/parameter/lint/in--authorization.ts b/packages/apidom-ls/src/config/openapi/parameter/lint/in--authorization.ts
new file mode 100644
index 0000000000..80a1ce274a
--- /dev/null
+++ b/packages/apidom-ls/src/config/openapi/parameter/lint/in--authorization.ts
@@ -0,0 +1,31 @@
+import { DiagnosticSeverity } from 'vscode-languageserver-types';
+
+import { OpenAPI3 } from '../../target-specs.ts';
+import ApilintCodes from '../../../codes.ts';
+
+const inAuthorizationLint = {
+  code: ApilintCodes.OPENAPI3_0_PARAMETER_FIELD_IN_AUTHORIZATION,
+  source: 'apilint',
+  message:
+    'Header Parameter named "Authorization" is ignored. Use the "securitySchemes" and "security" sections instead to define authorization',
+  severity: DiagnosticSeverity.Warning,
+  linterParams: ['^(?!\\b(A|a)uthorization\\b).*$'],
+  linterFunction: 'apilintValueRegex',
+  marker: 'value',
+  target: 'name',
+  data: {},
+  conditions: [
+    {
+      targets: [
+        {
+          path: 'in',
+        },
+      ],
+      function: 'apilintContainsValue',
+      params: ['header'],
+    },
+  ],
+  targetSpecs: OpenAPI3,
+};
+
+export default inAuthorizationLint;
diff --git a/packages/apidom-ls/src/config/openapi/parameter/lint/in--content-type.ts b/packages/apidom-ls/src/config/openapi/parameter/lint/in--content-type.ts
new file mode 100644
index 0000000000..d4db11f932
--- /dev/null
+++ b/packages/apidom-ls/src/config/openapi/parameter/lint/in--content-type.ts
@@ -0,0 +1,31 @@
+import { DiagnosticSeverity } from 'vscode-languageserver-types';
+
+import { OpenAPI3 } from '../../target-specs.ts';
+import ApilintCodes from '../../../codes.ts';
+
+const inContentTypeLint = {
+  code: ApilintCodes.OPENAPI3_0_PARAMETER_FIELD_IN_CONTENT_TYPE,
+  source: 'apilint',
+  message:
+    'Header Parameter named "Content-Type" is ignored. The values for the "Content-Type" header are defined by `requestBody.content.<media-type>`',
+  severity: DiagnosticSeverity.Warning,
+  linterParams: ['^(?!\\b(C|c)ontent-(T|t)ype\\b).*$'],
+  linterFunction: 'apilintValueRegex',
+  marker: 'value',
+  target: 'name',
+  data: {},
+  conditions: [
+    {
+      targets: [
+        {
+          path: 'in',
+        },
+      ],
+      function: 'apilintContainsValue',
+      params: ['header'],
+    },
+  ],
+  targetSpecs: OpenAPI3,
+};
+
+export default inContentTypeLint;
diff --git a/packages/apidom-ls/src/config/openapi/parameter/lint/in--multiple-body.ts b/packages/apidom-ls/src/config/openapi/parameter/lint/in--multiple-body.ts
new file mode 100644
index 0000000000..80ac42001c
--- /dev/null
+++ b/packages/apidom-ls/src/config/openapi/parameter/lint/in--multiple-body.ts
@@ -0,0 +1,27 @@
+import { DiagnosticSeverity } from 'vscode-languageserver-types';
+
+import { OpenAPI2 } from '../../target-specs.ts';
+import ApilintCodes from '../../../codes.ts';
+
+const inMultipleBody = {
+  code: ApilintCodes.OPENAPI2_PARAMETER_FIELD_IN_MULTIPLE_BODY,
+  source: 'apilint',
+  message: 'Multiple body parameters are not allowed',
+  severity: DiagnosticSeverity.Error,
+  linterFunction: 'apilintPropertyUniqueSiblingValue',
+  linterParams: ['parameters', 'in'],
+  marker: 'key',
+  markerTarget: 'in',
+  target: 'in',
+  conditions: [
+    {
+      targets: [{ path: 'in' }],
+      function: 'apilintContainsValue',
+      params: ['body'],
+    },
+  ],
+  data: {},
+  targetSpecs: OpenAPI2,
+};
+
+export default inMultipleBody;
diff --git a/packages/apidom-ls/src/config/openapi/parameter/lint/index.ts b/packages/apidom-ls/src/config/openapi/parameter/lint/index.ts
index 6e2bfd1f76..1ef0023df1 100644
--- a/packages/apidom-ls/src/config/openapi/parameter/lint/index.ts
+++ b/packages/apidom-ls/src/config/openapi/parameter/lint/index.ts
@@ -42,12 +42,18 @@ import uniqueItemsTypeLint from './unique-items--type.ts';
 import enumTypeLint from './enum--type.ts';
 import multipleOfTypeLint from './multiple-of--type.ts';
 import inPathTemplateLint from './in-path-template.ts';
+import uniqueNameLint from './unique-name.ts';
+import inAuthorizationLint from './in--authorization.ts';
+import inContentTypeLint from './in--content-type.ts';
+import inAcceptLint from './in--accept.ts';
+import inMultipleBody from './in--multiple-body.ts';
 
 const lints = [
   nameTypeLint,
   nameRequiredLint,
   inEquals2_0Lint,
   inEquals3_0__3_1Lint,
+  inAuthorizationLint,
   inRequiredLint,
   inValidLint,
   descriptionTypeLint,
@@ -81,6 +87,7 @@ const lints = [
   maxLengthTypeLint,
   minLengthTypeLint,
   uniqueItemsTypeLint,
+  uniqueNameLint,
   enumTypeLint,
   multipleOfTypeLint,
   requiredFields3_0__3_1Lint,
@@ -88,6 +95,9 @@ const lints = [
   allowedFields3_0Lint,
   allowedFields3_1Lint,
   inPathTemplateLint,
+  inContentTypeLint,
+  inAcceptLint,
+  inMultipleBody,
 ];
 
 export default lints;
diff --git a/packages/apidom-ls/src/config/openapi/parameter/lint/unique-name.ts b/packages/apidom-ls/src/config/openapi/parameter/lint/unique-name.ts
new file mode 100644
index 0000000000..15de868919
--- /dev/null
+++ b/packages/apidom-ls/src/config/openapi/parameter/lint/unique-name.ts
@@ -0,0 +1,21 @@
+import { DiagnosticSeverity } from 'vscode-languageserver-types';
+
+import ApilintCodes from '../../../codes.ts';
+import { LinterMeta } from '../../../../apidom-language-types.ts';
+import { OpenAPI2, OpenAPI3 } from '../../target-specs.ts';
+
+const parametersTypeLint: LinterMeta = {
+  code: ApilintCodes.OPENAPI2_PARAMETER_FIELD_NAME_UNIQUE,
+  source: 'apilint',
+  message: 'Name must be unique among all parameters',
+  severity: DiagnosticSeverity.Error,
+  linterFunction: 'apilintPropertyUniqueSiblingValue',
+  linterParams: ['parameters', 'name'],
+  marker: 'key',
+  markerTarget: 'name',
+  target: 'name',
+  data: {},
+  targetSpecs: [...OpenAPI2, ...OpenAPI3],
+};
+
+export default parametersTypeLint;
diff --git a/packages/apidom-ls/src/services/validation/linter-functions.ts b/packages/apidom-ls/src/services/validation/linter-functions.ts
index 196d248c27..9171020607 100644
--- a/packages/apidom-ls/src/services/validation/linter-functions.ts
+++ b/packages/apidom-ls/src/services/validation/linter-functions.ts
@@ -795,6 +795,30 @@ export const standardLinterfunctions: FunctionItem[] = [
       return true;
     },
   },
+  {
+    functionName: 'apilintPropertyUniqueSiblingValue',
+    function: (element, elementOrClasses, key) => {
+      const value = toValue(element);
+
+      const filterSiblingsOAS2 = (
+        el: Element & { key?: { content?: string }; content: { value?: string } },
+      ) => isString(el) && el.key?.content === key && toValue(el.content.value) === value;
+
+      const filterSiblingsOAS3 = (el: Element) =>
+        isObject(el) && el.hasKey(key) && toValue(el.get(key)) === value;
+
+      const elements = filter((el: Element) => {
+        const classes: string[] = toValue(el.getMetaProperty('classes', []));
+
+        return (
+          (elementOrClasses.includes(el.element) ||
+            classes.every((v) => elementOrClasses.includes(v))) &&
+          (filterSiblingsOAS2(el) || filterSiblingsOAS3(el))
+        );
+      }, element.parent?.parent?.parent);
+      return elements.length <= 1;
+    },
+  },
   {
     functionName: 'apilintChannelParameterExist',
     function: (element: Element): boolean => {
diff --git a/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-accept-3-0.yaml b/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-accept-3-0.yaml
new file mode 100644
index 0000000000..09a9d1b42c
--- /dev/null
+++ b/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-accept-3-0.yaml
@@ -0,0 +1,15 @@
+openapi: 3.0.0
+info:
+  version: 1.0.0
+  title: 'test'
+paths:
+  /:
+    get:
+      responses:
+        default:
+          description: 'test'
+      parameters:
+        - in: header
+          name: accept
+          content:
+            application/xml: {}
diff --git a/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-authorization-3-0.yaml b/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-authorization-3-0.yaml
new file mode 100644
index 0000000000..8084abb481
--- /dev/null
+++ b/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-authorization-3-0.yaml
@@ -0,0 +1,15 @@
+openapi: 3.0.0
+info:
+  version: 1.0.0
+  title: 'test'
+paths:
+  /:
+    get:
+      responses:
+        default:
+          description: 'test'
+      parameters:
+        - in: header
+          name: Authorization
+          content:
+            application/xml: {}
diff --git a/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-content-type-3-0.yaml b/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-content-type-3-0.yaml
new file mode 100644
index 0000000000..605172396d
--- /dev/null
+++ b/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-content-type-3-0.yaml
@@ -0,0 +1,15 @@
+openapi: 3.0.0
+info:
+  version: 1.0.0
+  title: 'test'
+paths:
+  /:
+    get:
+      responses:
+        default:
+          description: 'test'
+      parameters:
+        - in: header
+          name: content-type
+          content:
+            application/xml: {}
diff --git a/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-multiple-body.yaml b/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-multiple-body.yaml
new file mode 100644
index 0000000000..78f366d0b9
--- /dev/null
+++ b/packages/apidom-ls/test/fixtures/validation/oas/parameter-in-multiple-body.yaml
@@ -0,0 +1,19 @@
+swagger: '2.0'
+info:
+  title: 'test'
+  version: 1.0.0
+paths:
+  /:
+    get:
+      responses:
+        default:
+          description: 'test'
+      consumes:
+        - multipart/form-data
+      parameters:
+        - in: body
+          name: Else1
+          schema: {}
+        - in: body
+          name: Else2
+          schema: {}
diff --git a/packages/apidom-ls/test/fixtures/validation/oas/parameter-unique-name-2-0.yaml b/packages/apidom-ls/test/fixtures/validation/oas/parameter-unique-name-2-0.yaml
new file mode 100644
index 0000000000..51fcd46379
--- /dev/null
+++ b/packages/apidom-ls/test/fixtures/validation/oas/parameter-unique-name-2-0.yaml
@@ -0,0 +1,21 @@
+swagger: "2.0"
+info:
+  version: 1.0.0
+  title: 'test'
+paths:
+  /pets:
+    get:
+      responses:
+      parameters:
+        - name: pathLevel
+          type: string
+          in: query
+          description: tags to filter by
+          schema:
+            type: string
+        - name: pathLevel
+          type: string
+          in: query
+          description: tags to filter by
+          schema:
+            type: string
diff --git a/packages/apidom-ls/test/fixtures/validation/oas/parameter-unique-name-3-0.yaml b/packages/apidom-ls/test/fixtures/validation/oas/parameter-unique-name-3-0.yaml
new file mode 100644
index 0000000000..5bcb126e6d
--- /dev/null
+++ b/packages/apidom-ls/test/fixtures/validation/oas/parameter-unique-name-3-0.yaml
@@ -0,0 +1,19 @@
+openapi: 3.0.0
+info:
+  version: 1.0.0
+  title: 'test'
+paths:
+  /pets:
+    get:
+      responses:
+      parameters:
+        - name: pathLevel
+          in: query
+          description: tags to filter by
+          schema:
+            type: string
+        - name: pathLevel
+          in: query
+          description: tags to filter by
+          schema:
+            type: string
diff --git a/packages/apidom-ls/test/validate.ts b/packages/apidom-ls/test/validate.ts
index fb4564857a..8e8249faf8 100644
--- a/packages/apidom-ls/test/validate.ts
+++ b/packages/apidom-ls/test/validate.ts
@@ -3651,6 +3651,342 @@ describe('apidom-ls-validate', function () {
     languageService.terminate();
   });
 
+  it('oas 3.0 / yaml - parameter name should be unique', async function () {
+    const validationContext: ValidationContext = {
+      comments: DiagnosticSeverity.Error,
+      maxNumberOfProblems: 100,
+      relatedInformation: false,
+    };
+
+    const spec = fs
+      .readFileSync(
+        path.join(__dirname, 'fixtures', 'validation', 'oas', 'parameter-unique-name-3-0.yaml'),
+      )
+      .toString();
+    const doc: TextDocument = TextDocument.create(
+      'foo://bar/parameter-unique-name-3-0.yaml',
+      'yaml',
+      0,
+      spec,
+    );
+
+    const languageService: LanguageService = getLanguageService(contextNoSchema);
+
+    const result = await languageService.doValidation(doc, validationContext);
+    const expected: Diagnostic[] = [
+      {
+        code: 3103000,
+        data: {},
+        message: 'Name must be unique among all parameters',
+        range: {
+          end: {
+            character: 14,
+            line: 9,
+          },
+          start: {
+            character: 10,
+            line: 9,
+          },
+        },
+        severity: 1,
+        source: 'apilint',
+      },
+      {
+        code: 3103000,
+        data: {},
+        message: 'Name must be unique among all parameters',
+        range: {
+          end: {
+            character: 14,
+            line: 14,
+          },
+          start: {
+            character: 10,
+            line: 14,
+          },
+        },
+        severity: 1,
+        source: 'apilint',
+      },
+    ];
+    assert.deepEqual(result, expected as Diagnostic[]);
+
+    languageService.terminate();
+  });
+
+  it('oas 2.0 / yaml - parameter name should be unique', async function () {
+    const validationContext: ValidationContext = {
+      comments: DiagnosticSeverity.Error,
+      maxNumberOfProblems: 100,
+      relatedInformation: false,
+    };
+
+    const spec = fs
+      .readFileSync(
+        path.join(__dirname, 'fixtures', 'validation', 'oas', 'parameter-unique-name-2-0.yaml'),
+      )
+      .toString();
+    const doc: TextDocument = TextDocument.create(
+      'foo://bar/parameter-unique-name-2-0.yaml',
+      'yaml',
+      0,
+      spec,
+    );
+
+    const languageService: LanguageService = getLanguageService(contextNoSchema);
+
+    const result = await languageService.doValidation(doc, validationContext);
+    const expected: Diagnostic[] = [
+      {
+        code: 3103000,
+        data: {},
+        message: 'Name must be unique among all parameters',
+        range: {
+          end: {
+            character: 14,
+            line: 9,
+          },
+          start: {
+            character: 10,
+            line: 9,
+          },
+        },
+        severity: 1,
+        source: 'apilint',
+      },
+      {
+        code: 3103000,
+        data: {},
+        message: 'Name must be unique among all parameters',
+        range: {
+          end: {
+            character: 14,
+            line: 15,
+          },
+          start: {
+            character: 10,
+            line: 15,
+          },
+        },
+        severity: 1,
+        source: 'apilint',
+      },
+    ];
+    assert.deepEqual(result, expected as Diagnostic[]);
+
+    languageService.terminate();
+  });
+
+  it('oas 3.0 / yaml - parameter Authorization is ignored', async function () {
+    const validationContext: ValidationContext = {
+      comments: DiagnosticSeverity.Error,
+      maxNumberOfProblems: 100,
+      relatedInformation: false,
+    };
+
+    const spec = fs
+      .readFileSync(
+        path.join(
+          __dirname,
+          'fixtures',
+          'validation',
+          'oas',
+          'parameter-in-authorization-3-0.yaml',
+        ),
+      )
+      .toString();
+    const doc: TextDocument = TextDocument.create(
+      'foo://bar/parameter-in-authorization-3-0.yaml',
+      'yaml',
+      0,
+      spec,
+    );
+
+    const languageService: LanguageService = getLanguageService(contextNoSchema);
+
+    const result = await languageService.doValidation(doc, validationContext);
+    const expected: Diagnostic[] = [
+      {
+        code: 5150303,
+        data: {},
+        message:
+          'Header Parameter named "Authorization" is ignored. Use the "securitySchemes" and "security" sections instead to define authorization',
+        range: {
+          end: {
+            character: 29,
+            line: 12,
+          },
+          start: {
+            character: 16,
+            line: 12,
+          },
+        },
+        severity: 2,
+        source: 'apilint',
+      },
+    ];
+    assert.deepEqual(result, expected as Diagnostic[]);
+
+    languageService.terminate();
+  });
+
+  it('oas 3.0 / yaml - parameter content-type is ignored', async function () {
+    const validationContext: ValidationContext = {
+      comments: DiagnosticSeverity.Error,
+      maxNumberOfProblems: 100,
+      relatedInformation: false,
+    };
+
+    const spec = fs
+      .readFileSync(
+        path.join(__dirname, 'fixtures', 'validation', 'oas', 'parameter-in-content-type-3-0.yaml'),
+      )
+      .toString();
+    const doc: TextDocument = TextDocument.create(
+      'foo://bar/parameter-in-authorization-3-0.yaml',
+      'yaml',
+      0,
+      spec,
+    );
+
+    const languageService: LanguageService = getLanguageService(contextNoSchema);
+
+    const result = await languageService.doValidation(doc, validationContext);
+    const expected: Diagnostic[] = [
+      {
+        code: 5150304,
+        data: {},
+        message:
+          'Header Parameter named "Content-Type" is ignored. The values for the "Content-Type" header are defined by `requestBody.content.<media-type>`',
+        range: {
+          end: {
+            character: 28,
+            line: 12,
+          },
+          start: {
+            character: 16,
+            line: 12,
+          },
+        },
+        severity: 2,
+        source: 'apilint',
+      },
+    ];
+    assert.deepEqual(result, expected as Diagnostic[]);
+
+    languageService.terminate();
+  });
+
+  it('oas 3.0 / yaml - parameter accept is ignored', async function () {
+    const validationContext: ValidationContext = {
+      comments: DiagnosticSeverity.Error,
+      maxNumberOfProblems: 100,
+      relatedInformation: false,
+    };
+
+    const spec = fs
+      .readFileSync(
+        path.join(__dirname, 'fixtures', 'validation', 'oas', 'parameter-in-accept-3-0.yaml'),
+      )
+      .toString();
+    const doc: TextDocument = TextDocument.create(
+      'foo://bar/parameter-in-accept-3-0.yaml',
+      'yaml',
+      0,
+      spec,
+    );
+
+    const languageService: LanguageService = getLanguageService(contextNoSchema);
+
+    const result = await languageService.doValidation(doc, validationContext);
+    const expected: Diagnostic[] = [
+      {
+        code: 5150304,
+        data: {},
+        message:
+          'Header Parameter named "Accept" is ignored. The values for the "Accept" header are defined by `requestBody.content.<media-type>`',
+        range: {
+          end: {
+            character: 22,
+            line: 12,
+          },
+          start: {
+            character: 16,
+            line: 12,
+          },
+        },
+        severity: 2,
+        source: 'apilint',
+      },
+    ];
+    assert.deepEqual(result, expected as Diagnostic[]);
+
+    languageService.terminate();
+  });
+
+  it('oas 2.0 / yaml - Multiple body parameters are not allowed', async function () {
+    const validationContext: ValidationContext = {
+      comments: DiagnosticSeverity.Error,
+      maxNumberOfProblems: 100,
+      relatedInformation: false,
+    };
+
+    const spec = fs
+      .readFileSync(
+        path.join(__dirname, 'fixtures', 'validation', 'oas', 'parameter-in-multiple-body.yaml'),
+      )
+      .toString();
+    const doc: TextDocument = TextDocument.create(
+      'foo://bar/parameter-in-multiple-body.yaml',
+      'yaml',
+      0,
+      spec,
+    );
+
+    const languageService: LanguageService = getLanguageService(contextNoSchema);
+
+    const result = await languageService.doValidation(doc, validationContext);
+    const expected: Diagnostic[] = [
+      {
+        code: 3100203,
+        data: {},
+        message: 'Multiple body parameters are not allowed',
+        range: {
+          end: {
+            character: 12,
+            line: 13,
+          },
+          start: {
+            character: 10,
+            line: 13,
+          },
+        },
+        severity: 1,
+        source: 'apilint',
+      },
+      {
+        code: 3100203,
+        data: {},
+        message: 'Multiple body parameters are not allowed',
+        range: {
+          end: {
+            character: 12,
+            line: 16,
+          },
+          start: {
+            character: 10,
+            line: 16,
+          },
+        },
+        severity: 1,
+        source: 'apilint',
+      },
+    ];
+    assert.deepEqual(result, expected as Diagnostic[]);
+
+    languageService.terminate();
+  });
+
   it('oas 3.1 / yaml - parameter object should be defined within path template', async function () {
     const validationContext: ValidationContext = {
       comments: DiagnosticSeverity.Error,