# require-param-type * [Options](#user-content-require-param-type-options) * [`contexts`](#user-content-require-param-type-options-contexts) * [`defaultDestructuredRootType`](#user-content-require-param-type-options-defaultdestructuredroottype) * [`setDefaultDestructuredRootType`](#user-content-require-param-type-options-setdefaultdestructuredroottype) * [Context and settings](#user-content-require-param-type-context-and-settings) * [Failing examples](#user-content-require-param-type-failing-examples) * [Passing examples](#user-content-require-param-type-passing-examples) Requires that each `@param` tag has a `type` value (within curly brackets). Will exempt destructured roots and their children if `settings.exemptDestructuredRootsFromChecks` is set to `true` (e.g., `@param props` will be exempted from requiring a type given `function someFunc ({child1, child2})`). ## Options A single options object has the following properties. ### contexts Set this to an array of strings representing the AST context (or an object with optional `context` and `comment` properties) where you wish the rule to be applied. `context` defaults to `any` and `comment` defaults to no specific comment context. Overrides the default contexts (`ArrowFunctionExpression`, `FunctionDeclaration`, `FunctionExpression`). Set to `"any"` if you want the rule to apply to any JSDoc block throughout your files (as is necessary for finding function blocks not attached to a function declaration or expression, i.e., `@callback` or `@function` (or its aliases `@func` or `@method`) (including those associated with an `@interface`). See the ["AST and Selectors"](../advanced.md#ast-and-selectors) section of our Advanced docs for more on the expected format. ### defaultDestructuredRootType The type string to set by default for destructured roots. Defaults to "object". ### setDefaultDestructuredRootType Whether to set a default destructured root type. For example, you may wish to avoid manually having to set the type for a `@param` corresponding to a destructured root object as it is always going to be an object. Uses `defaultDestructuredRootType` for the type string. Defaults to `false`. ## Context and settings ||| |---|---| |Context|`ArrowFunctionExpression`, `FunctionDeclaration`, `FunctionExpression`; others when `contexts` option enabled| |Tags|`param`| |Aliases|`arg`, `argument`| |Recommended|true| |Options|`contexts`, `defaultDestructuredRootType`, `setDefaultDestructuredRootType`| |Settings|`exemptDestructuredRootsFromChecks`| ## Failing examples The following patterns are considered problems: ````ts /** * @param foo */ function quux (foo) { } // Message: Missing JSDoc @param "foo" type. /** * @param {a xxx */ function quux () { } // Message: Missing JSDoc @param "" type. /** * @param foo */ function quux (foo) { } // "jsdoc/require-param-type": ["error"|"warn", {"contexts":["any"]}] // Message: Missing JSDoc @param "foo" type. /** * @function * @param foo */ // "jsdoc/require-param-type": ["error"|"warn", {"contexts":["any"]}] // Message: Missing JSDoc @param "foo" type. /** * @callback * @param foo */ // "jsdoc/require-param-type": ["error"|"warn", {"contexts":["any"]}] // Message: Missing JSDoc @param "foo" type. /** * @arg foo */ function quux (foo) { } // Settings: {"jsdoc":{"tagNamePreference":{"param":"arg"}}} // Message: Missing JSDoc @arg "foo" type. /** * @param foo */ function quux (foo) { } // Settings: {"jsdoc":{"tagNamePreference":{"param":false}}} // Message: Unexpected tag `@param` /** * @param {number} foo * @param root * @param {boolean} baz */ function quux (foo, {bar}, baz) { } // "jsdoc/require-param-type": ["error"|"warn", {"setDefaultDestructuredRootType":true}] // Message: Missing root type for @param. /** * @param {number} foo * @param root * @param {boolean} baz */ function quux (foo, {bar}, baz) { } // "jsdoc/require-param-type": ["error"|"warn", {"defaultDestructuredRootType":"Object","setDefaultDestructuredRootType":true}] // Message: Missing root type for @param. /** * @param {number} foo * @param root * @param {boolean} baz */ function quux (foo, {bar}, baz) { } // "jsdoc/require-param-type": ["error"|"warn", {"setDefaultDestructuredRootType":false}] // Message: Missing JSDoc @param "root" type. ```` ## Passing examples The following patterns are not considered problems: ````ts /** * */ function quux (foo) { } /** * @param {number} foo */ function quux (foo) { } /** * @param {number} foo */ function quux (foo) { } // "jsdoc/require-param-type": ["error"|"warn", {"contexts":["any"]}] /** * @function * @param foo */ /** * @callback * @param foo */ /** * @param {number} foo * @param root * @param {boolean} baz */ function quux (foo, {bar}, baz) { } // Settings: {"jsdoc":{"exemptDestructuredRootsFromChecks":true}} /** * @param {number} foo * @param root * @param root.bar */ function quux (foo, {bar: {baz}}) { } // Settings: {"jsdoc":{"exemptDestructuredRootsFromChecks":true}} ````