Only one of 'sequence', 'scalar' and 'mapping' can be used for kind.

types/js-yaml/index.d.ts

@@ -9,7 +9,7 @@ export function load(str: string, opts?: LoadOptions): any;
 
 export class Type implements TypeConstructorOptions {
 	constructor(tag: string, opts?: TypeConstructorOptions);
-	kind: string | null;
+	kind: 'sequence' | 'scalar' | 'mapping' | null;
 	resolve(data: any): boolean;
 	construct(data: any): any;
 	instanceOf: object | null;
@@ -66,7 +66,7 @@ export interface DumpOptions {
 }
 
 export interface TypeConstructorOptions {
-	kind?: string;
+	kind?: 'sequence' | 'scalar' | 'mapping';
 	resolve?: (data: any) => boolean;
 	construct?: (data: any) => any;
 	instanceOf?: object;

types/js-yaml/js-yaml-tests.ts

@@ -20,7 +20,7 @@ let schemaDefinition: SchemaDefinition = {
 	include: array
 };
 let typeConstructorOptions: TypeConstructorOptions = {
-	kind: str,
+	kind: "scalar",
 	resolve: fn,
 	construct: fn,
 	instanceOf: obj,