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Schema Reference

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# Schema Reference ## JSON-RPC ## Common Types ## Errors ## Content ## `completion/complete` ## `elicitation/create` ## `notifications/cancelled` ## `notifications/message` ## `notifications/progress` ## `notifications/prompts/list_changed` ## `notifications/resources/list_changed` ## `notifications/resources/updated` ## `notifications/subscriptions/acknowledged` ## `notifications/tools/list_changed` ## Multi Round-Trip ## `prompts/get` ## `prompts/list` ## `resources/list` ## `resources/read` ## `resources/templates/list` ## `roots/list` ## `sampling/createMessage` ## `server/discover` ## `subscriptions/listen` ## `tools/call` ## `tools/list`

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# Schema Reference

<div id="schema-reference" />

## JSON-RPC

<div class="type">
  ### `JSONRPCErrorResponse`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">JSONRPCErrorResponse</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#jsonrpcerrorresponse-jsonrpc">jsonrpc</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">"2.0"</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#jsonrpcerrorresponse-id">id</a><span class="tsd-signature-symbol">?:</span> <a href="#requestid" class="tsd-signature-type tsd-kind-type-alias">RequestId</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#jsonrpcerrorresponse-error">error</a><span class="tsd-signature-symbol">:</span> <a href="#error" class="tsd-signature-type tsd-kind-interface">Error</a><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>A response to a request that indicates an error occurred.</p> </div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="jsonrpcerrorresponse-jsonrpc" data-typedoc-h="3"><span>jsonrpc: "2.0"</span><a href="#jsonrpcerrorresponse-jsonrpc" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="jsonrpcerrorresponse-id" data-typedoc-h="3"><span>id?: RequestId</span><a href="#jsonrpcerrorresponse-id" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="jsonrpcerrorresponse-error" data-typedoc-h="3"><span>error: Error</span><a href="#jsonrpcerrorresponse-error" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section>
</div>

<div class="type">
  ### `JSONRPCMessage`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">JSONRPCMessage</span><span class="tsd-signature-symbol">:</span> <a href="#jsonrpcrequest" class="tsd-signature-type tsd-kind-interface">JSONRPCRequest</a> <span class="tsd-signature-symbol">|</span> <a href="#jsonrpcnotification" class="tsd-signature-type tsd-kind-interface">JSONRPCNotification</a> <span class="tsd-signature-symbol">|</span> <a href="#jsonrpcresponse" class="tsd-signature-type tsd-kind-type-alias">JSONRPCResponse</a></div> <div class="tsd-comment tsd-typography"><p>Refers to any valid JSON-RPC object that can be decoded off the wire, or encoded to be sent.</p> </div>
</div>

<div class="type">
  ### `JSONRPCNotification`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">JSONRPCNotification</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#jsonrpcnotification-method">method</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#jsonrpcnotification-params">params</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-symbol">\{</span> <span class="tsd-signature-symbol">\[</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">any</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#jsonrpcnotification-jsonrpc">jsonrpc</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">"2.0"</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>A notification which does not expect a response.</p> </div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="jsonrpcnotification-method" data-typedoc-h="3"><span>method: string</span><a href="#jsonrpcnotification-method" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from Notification.method</p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="jsonrpcnotification-params" data-typedoc-h="3"><span>params?: \{ \[key: string]: any }</span><a href="#jsonrpcnotification-params" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from Notification.params</p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="jsonrpcnotification-jsonrpc" data-typedoc-h="3"><span>jsonrpc: "2.0"</span><a href="#jsonrpcnotification-jsonrpc" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section>
</div>

<div class="type">
  ### `JSONRPCRequest`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">JSONRPCRequest</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#jsonrpcrequest-method">method</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#jsonrpcrequest-params">params</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-symbol">\{</span> <span class="tsd-signature-symbol">\[</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">any</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#jsonrpcrequest-jsonrpc">jsonrpc</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">"2.0"</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#jsonrpcrequest-id">id</a><span class="tsd-signature-symbol">:</span> <a href="#requestid" class="tsd-signature-type tsd-kind-type-alias">RequestId</a><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>A request that expects a response.</p> </div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="jsonrpcrequest-method" data-typedoc-h="3"><span>method: string</span><a href="#jsonrpcrequest-method" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from Request.method</p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="jsonrpcrequest-params" data-typedoc-h="3"><span>params?: \{ \[key: string]: any }</span><a href="#jsonrpcrequest-params" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from Request.params</p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="jsonrpcrequest-jsonrpc" data-typedoc-h="3"><span>jsonrpc: "2.0"</span><a href="#jsonrpcrequest-jsonrpc" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="jsonrpcrequest-id" data-typedoc-h="3"><span>id: RequestId</span><a href="#jsonrpcrequest-id" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section>
</div>

<div class="type">
  ### `JSONRPCResponse`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">JSONRPCResponse</span><span class="tsd-signature-symbol">:</span> <a href="#jsonrpcresultresponse" class="tsd-signature-type tsd-kind-interface">JSONRPCResultResponse</a> <span class="tsd-signature-symbol">|</span> <a href="#jsonrpcerrorresponse" class="tsd-signature-type tsd-kind-interface">JSONRPCErrorResponse</a></div> <div class="tsd-comment tsd-typography"><p>A response to a request, containing either the result or error.</p> </div>
</div>

<div class="type">
  ### `JSONRPCResultResponse`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">JSONRPCResultResponse</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#jsonrpcresultresponse-jsonrpc">jsonrpc</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">"2.0"</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#jsonrpcresultresponse-id">id</a><span class="tsd-signature-symbol">:</span> <a href="#requestid" class="tsd-signature-type tsd-kind-type-alias">RequestId</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#jsonrpcresultresponse-result">result</a><span class="tsd-signature-symbol">:</span> <a href="#result" class="tsd-signature-type tsd-kind-interface">Result</a><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>A successful (non-error) response to a request.</p> </div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="jsonrpcresultresponse-jsonrpc" data-typedoc-h="3"><span>jsonrpc: "2.0"</span><a href="#jsonrpcresultresponse-jsonrpc" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="jsonrpcresultresponse-id" data-typedoc-h="3"><span>id: RequestId</span><a href="#jsonrpcresultresponse-id" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="jsonrpcresultresponse-result" data-typedoc-h="3"><span>result: Result</span><a href="#jsonrpcresultresponse-result" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section>
</div>

## Common Types

<div class="type">
  ### `Annotations`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">Annotations</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#annotations-audience">audience</a><span class="tsd-signature-symbol">?:</span> <a href="#role" class="tsd-signature-type tsd-kind-type-alias">Role</a><span class="tsd-signature-symbol">\[]</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#annotations-priority">priority</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">number</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#annotations-lastmodified">lastModified</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Optional annotations for the client. The client can use annotations to inform how objects are used or displayed</p> </div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="annotations-audience" data-typedoc-h="3"><span>audience?: Role\[]</span><a href="#annotations-audience" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Describes who the intended audience of this object or data is.</p> <p>It can include multiple entries to indicate content useful for multiple audiences (e.g., <code>\["user", "assistant"]</code>).</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="annotations-priority" data-typedoc-h="3"><span>priority?: number</span><a href="#annotations-priority" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Describes how important this data is for operating the server.</p> <p>A value of 1 means "most important," and indicates that the data is
  effectively required, while 0 means "least important," and indicates that
  the data is entirely optional.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="annotations-lastmodified" data-typedoc-h="3"><span>lastModified?: string</span><a href="#annotations-lastmodified" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>The moment the resource was last modified, as an ISO 8601 formatted string.</p> <p>Should be an ISO 8601 formatted string (e.g., "2025-01-12T15:00:58Z").</p> <p>Examples: last activity timestamp in an open file, timestamp when the resource
  was attached, etc.</p> </div></section>
</div>

<div class="type">
  ### `Cursor`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">Cursor</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span></div> <div class="tsd-comment tsd-typography"><p>An opaque token used to represent a cursor for pagination.</p> </div>
</div>

<div class="type">
  ### `EmptyResult`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">EmptyResult</span><span class="tsd-signature-symbol">:</span> <a href="#result" class="tsd-signature-type tsd-kind-interface">Result</a></div> <div class="tsd-comment tsd-typography"><p>A result that indicates success but carries no data.</p> </div>
</div>

<div class="type">
  ### `Icon`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">Icon</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#icon-src">src</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#icon-mimetype">mimeType</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#icon-sizes">sizes</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">\[]</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#icon-theme">theme</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">"light"</span> <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"dark"</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>An optionally-sized icon that can be displayed in a user interface.</p> </div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="icon-src" data-typedoc-h="3"><span>src: string</span><a href="#icon-src" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>A standard URI pointing to an icon resource. May be an HTTP/HTTPS URL or a <code>data:</code> URI with Base64-encoded image data.</p> <p>Consumers SHOULD take steps to ensure URLs serving icons are from the
  same domain as the client/server or a trusted domain.</p> <p>Consumers SHOULD take appropriate precautions when consuming SVGs as they can contain
  executable JavaScript.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="icon-mimetype" data-typedoc-h="3"><span>mimeType?: string</span><a href="#icon-mimetype" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Optional MIME type override if the source MIME type is missing or generic.
  For example: <code>"image/png"</code>, <code>"image/jpeg"</code>, or <code>"image/svg+xml"</code>.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="icon-sizes" data-typedoc-h="3"><span>sizes?: string\[]</span><a href="#icon-sizes" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Optional array of strings that specify sizes at which the icon can be used.
  Each string should be in WxH format (e.g., <code>"48x48"</code>, <code>"96x96"</code>) or <code>"any"</code> for scalable formats like SVG.</p> <p>If not provided, the client should assume that the icon can be used at any size.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="icon-theme" data-typedoc-h="3"><span>theme?: "light" | "dark"</span><a href="#icon-theme" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Optional specifier for the theme this icon is designed for. <code>"light"</code> indicates
  the icon is designed to be used with a light background, and <code>"dark"</code> indicates
  the icon is designed to be used with a dark background.</p> <p>If not provided, the client should assume the icon can be used with any theme.</p> </div></section>
</div>

<div class="type">
  ### `InputResponseRequestParams`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">InputResponseRequestParams</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#inputresponserequestparams-_meta">\_meta</a><span class="tsd-signature-symbol">:</span> <a href="#requestmetaobject" class="tsd-signature-type tsd-kind-interface">RequestMetaObject</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#inputresponserequestparams-inputresponses">inputResponses</a><span class="tsd-signature-symbol">?:</span> <a href="#inputresponses" class="tsd-signature-type tsd-kind-interface">InputResponses</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#inputresponserequestparams-requeststate">requestState</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Common params for any request.</p> </div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="inputresponserequestparams-_meta" data-typedoc-h="3"><span>\_meta: RequestMetaObject</span><a href="#inputresponserequestparams-_meta" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from <a href="#requestparams">RequestParams</a>.<a href="#requestparams-_meta">\_meta</a></p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="inputresponserequestparams-inputresponses" data-typedoc-h="3"><span>inputResponses?: InputResponses</span><a href="#inputresponserequestparams-inputresponses" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="inputresponserequestparams-requeststate" data-typedoc-h="3"><span>requestState?: string</span><a href="#inputresponserequestparams-requeststate" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section>
</div>

<div class="type">
  ### `JSONArray`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">JSONArray</span><span class="tsd-signature-symbol">:</span> <a href="#jsonvalue" class="tsd-signature-type tsd-kind-type-alias">JSONValue</a><span class="tsd-signature-symbol">\[]</span></div>
</div>

<div class="type">
  ### `JSONObject`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">JSONObject</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-symbol">\{</span> <span class="tsd-signature-symbol">\[</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <a href="#jsonvalue" class="tsd-signature-type tsd-kind-type-alias">JSONValue</a> <span class="tsd-signature-symbol">}</span></div> <div class="tsd-type-declaration"> <div data-typedoc-h="4">Type Declaration</div> <ul class="tsd-parameters"> <li class="tsd-parameter-index-signature"> <div data-typedoc-h="5"><span class="tsd-signature-symbol">\[</span><span class="tsd-kind-parameter">key</span>: <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <a href="#jsonvalue" class="tsd-signature-type tsd-kind-type-alias">JSONValue</a></div></li></ul></div>
</div>

<div class="type">
  ### `JSONValue`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">JSONValue</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span> <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">number</span> <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">boolean</span> <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">null</span> <span class="tsd-signature-symbol">|</span> <a href="#jsonobject" class="tsd-signature-type tsd-kind-type-alias">JSONObject</a> <span class="tsd-signature-symbol">|</span> <a href="#jsonarray" class="tsd-signature-type tsd-kind-type-alias">JSONArray</a></div>
</div>

<div class="type">
  ### `LoggingLevel`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">LoggingLevel</span><span class="tsd-signature-symbol">:</span><br />  <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"debug"</span><br />  <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"info"</span><br />  <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"notice"</span><br />  <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"warning"</span><br />  <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"error"</span><br />  <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"critical"</span><br />  <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"alert"</span><br />  <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"emergency"</span></div> <div class="tsd-comment tsd-typography"><p>The severity of a log message.</p> <p>These map to syslog message severities, as specified in RFC-5424: <a href="https://datatracker.ietf.org/doc/html/rfc5424#section-6.2.1">[https://datatracker.ietf.org/doc/html/rfc5424#section-6.2.1](https://datatracker.ietf.org/doc/html/rfc5424#section-6.2.1)</a></p> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-deprecated"> <div class="tsd-anchor-link" data-typedoc-h="4">Deprecated</div><p>Deprecated as of protocol version 2026-07-28 (SEP-2577).
  Remains in the specification for at least twelve months; see the
  deprecated features registry.</p> </div></div>
</div>

<div class="type">
  ### `MetaObject`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">MetaObject</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">Record</span><span class="tsd-signature-symbol">\<</span><span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">,</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">></span></div> <div class="tsd-comment tsd-typography"><p>Represents the contents of a <code>\_meta</code> field, which clients and servers use to attach additional metadata to their interactions.</p> <p>Certain key names are reserved by MCP for protocol-level metadata; implementations MUST NOT make assumptions about values at these keys. Additionally, specific schema definitions may reserve particular names for purpose-specific metadata, as declared in those definitions.</p> <p>Valid keys have two segments:</p> <p><strong>Prefix:</strong></p> <ul> <li>Optional — if specified, MUST be a series of <em>labels</em> separated by dots (<code>.</code>), followed by a slash (<code>/</code>).</li> <li>Labels MUST start with a letter and end with a letter or digit. Interior characters may be letters, digits, or hyphens (<code>-</code>).</li> <li>Implementations SHOULD use reverse DNS notation (e.g., <code>com.example/</code> rather than <code>example.com/</code>).</li> <li>Any prefix where the second label is <code>modelcontextprotocol</code> or <code>mcp</code> is <strong>reserved</strong> for MCP use. For example: <code>io.modelcontextprotocol/</code>, <code>dev.mcp/</code>, <code>org.modelcontextprotocol.api/</code>, and <code>com.mcp.tools/</code> are all reserved. However, <code>com.example.mcp/</code> is NOT reserved, as the second label is <code>example</code>.</li> </ul> <p><strong>Name:</strong></p> <ul> <li>Unless empty, MUST start and end with an alphanumeric character (<code>\[a-z0-9A-Z]</code>).</li> <li>Interior characters may be alphanumeric, hyphens (<code>-</code>), underscores (<code>\_</code>), or dots (<code>.</code>).</li> </ul> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-see"> <div class="tsd-anchor-link" data-typedoc-h="4">See</div><p><a href="/specification/2026-07-28/basic/index#meta">General fields: <code>\_meta</code></a> for more details.</p> </div></div>
</div>

<div class="type">
  ### `NotificationMetaObject`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">NotificationMetaObject</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#notificationmetaobject-iomodelcontextprotocolsubscriptionid">"io.modelcontextprotocol/subscriptionId"</a><span class="tsd-signature-symbol">?:</span> <a href="#requestid" class="tsd-signature-type tsd-kind-type-alias">RequestId</a><span class="tsd-signature-symbol">;</span><br />  <span class="tsd-signature-symbol">\[</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Extends <a href="#metaobject" class="tsd-kind-type-alias">MetaObject</a> with additional notification-specific fields. All key naming rules from <code>MetaObject</code> apply.</p> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-see"> <div class="tsd-anchor-link" data-typedoc-h="4">See</div><ul> <li><a href="#metaobject" class="tsd-kind-type-alias">MetaObject</a> for key naming rules and reserved prefixes.</li> <li><a href="/specification/2026-07-28/basic/index#meta">General fields: <code>\_meta</code></a> for more details.</li> </ul> </div></div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="notificationmetaobject-iomodelcontextprotocolsubscriptionid" data-typedoc-h="3"><span>"io.modelcontextprotocol/subscriptionId"?: RequestId</span><a href="#notificationmetaobject-iomodelcontextprotocolsubscriptionid" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Identifies the subscription stream a notification was delivered on. The
  server MUST include this key on every notification delivered via a <a href="#subscriptionslistenrequest" class="tsd-kind-interface">subscriptions/listen</a> stream, so the
  client can correlate the notification with the originating subscription.
  The key is absent on notifications not delivered via a subscription
  stream (e.g. progress notifications for an in-flight request), which is
  why it is optional here.</p> <p>The value is the JSON-RPC ID of the <code>subscriptions/listen</code> request that
  opened the stream.</p> </div></section>
</div>

<div class="type">
  ### `NotificationParams`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">NotificationParams</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#notificationparams-_meta">\_meta</a><span class="tsd-signature-symbol">?:</span> <a href="#notificationmetaobject" class="tsd-signature-type tsd-kind-interface">NotificationMetaObject</a><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Common params for any notification.</p> </div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="notificationparams-_meta" data-typedoc-h="3"><span>\_meta?: NotificationMetaObject</span><a href="#notificationparams-_meta" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section>
</div>

<div class="type">
  ### `PaginatedRequestParams`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">PaginatedRequestParams</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#paginatedrequestparams-_meta">\_meta</a><span class="tsd-signature-symbol">:</span> <a href="#requestmetaobject" class="tsd-signature-type tsd-kind-interface">RequestMetaObject</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#paginatedrequestparams-cursor">cursor</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Common params for paginated requests.</p> </div> <div class="tsd-comment tsd-typography"> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: List request with cursor<a href="#paginatedrequestparams-example-list-request-with-cursor" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="paginatedrequestparams-example-list-request-with-cursor"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"\_meta"</span><span class="hl-0">: \{</span><br /><span class="hl-0">    </span><span class="hl-1">"io.modelcontextprotocol/protocolVersion"</span><span class="hl-0">: </span><span class="hl-2">"2026-07-28"</span><span class="hl-0">,</span><br /><span class="hl-0">    </span><span class="hl-1">"io.modelcontextprotocol/clientInfo"</span><span class="hl-0">: \{</span><br /><span class="hl-0">      </span><span class="hl-1">"name"</span><span class="hl-0">: </span><span class="hl-2">"ExampleClient"</span><span class="hl-0">,</span><br /><span class="hl-0">      </span><span class="hl-1">"version"</span><span class="hl-0">: </span><span class="hl-2">"1.0.0"</span><br /><span class="hl-0">    },</span><br /><span class="hl-0">    </span><span class="hl-1">"io.modelcontextprotocol/clientCapabilities"</span><span class="hl-0">: \{}</span><br /><span class="hl-0">  },</span><br /><span class="hl-0">  </span><span class="hl-1">"cursor"</span><span class="hl-0">: </span><span class="hl-2">"eyJwYWdlIjogMn0="</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="paginatedrequestparams-_meta" data-typedoc-h="3"><span>\_meta: RequestMetaObject</span><a href="#paginatedrequestparams-_meta" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from <a href="#requestparams">RequestParams</a>.<a href="#requestparams-_meta">\_meta</a></p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="paginatedrequestparams-cursor" data-typedoc-h="3"><span>cursor?: string</span><a href="#paginatedrequestparams-cursor" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>An opaque token representing the current pagination position.
  If provided, the server should return results starting after this cursor.</p> </div></section>
</div>

<div class="type">
  ### `ProgressToken`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">ProgressToken</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span> <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">number</span></div> <div class="tsd-comment tsd-typography"><p>A progress token, used to associate progress notifications with the original request.</p> </div>
</div>

<div class="type">
  ### `RequestId`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">RequestId</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span> <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">number</span></div> <div class="tsd-comment tsd-typography"><p>A uniquely identifying ID for a request in JSON-RPC.</p> </div>
</div>

<div class="type">
  ### `RequestMetaObject`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">RequestMetaObject</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#requestmetaobject-progresstoken">progressToken</a><span class="tsd-signature-symbol">?:</span> <a href="#progresstoken" class="tsd-signature-type tsd-kind-type-alias">ProgressToken</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#requestmetaobject-iomodelcontextprotocolprotocolversion">"io.modelcontextprotocol/protocolVersion"</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#requestmetaobject-iomodelcontextprotocolclientinfo">"io.modelcontextprotocol/clientInfo"</a><span class="tsd-signature-symbol">?:</span> <a href="#implementation" class="tsd-signature-type tsd-kind-interface">Implementation</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#requestmetaobject-iomodelcontextprotocolclientcapabilities">"io.modelcontextprotocol/clientCapabilities"</a><span class="tsd-signature-symbol">:</span> <a href="#clientcapabilities" class="tsd-signature-type tsd-kind-interface">ClientCapabilities</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#requestmetaobject-iomodelcontextprotocolloglevel">"io.modelcontextprotocol/logLevel"</a><span class="tsd-signature-symbol">?:</span> <a href="#logginglevel" class="tsd-signature-type tsd-kind-type-alias">LoggingLevel</a><span class="tsd-signature-symbol">;</span><br />  <span class="tsd-signature-symbol">\[</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Extends <a href="#metaobject" class="tsd-kind-type-alias">MetaObject</a> with additional request-specific fields. All key naming rules from <code>MetaObject</code> apply.</p> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-see"> <div class="tsd-anchor-link" data-typedoc-h="4">See</div><ul> <li><a href="#metaobject" class="tsd-kind-type-alias">MetaObject</a> for key naming rules and reserved prefixes.</li> <li><a href="/specification/2026-07-28/basic/index#meta">General fields: <code>\_meta</code></a> for more details.</li> </ul> </div></div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="requestmetaobject-progresstoken" data-typedoc-h="3"><span>progressToken?: ProgressToken</span><a href="#requestmetaobject-progresstoken" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>If specified, the caller is requesting out-of-band progress notifications for this request (as represented by <a href="#progressnotification" class="tsd-kind-interface">notifications/progress</a>). The value of this parameter is an opaque token that will be attached to any subsequent notifications. The receiver is not obligated to provide these notifications.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="requestmetaobject-iomodelcontextprotocolprotocolversion" data-typedoc-h="3"><span>"io.modelcontextprotocol/protocolVersion": string</span><a href="#requestmetaobject-iomodelcontextprotocolprotocolversion" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>The MCP Protocol Version being used for this request. Required.</p> <p>For the HTTP transport, this value MUST match the <code>MCP-Protocol-Version</code>
  header; otherwise the server MUST return a <code>400 Bad Request</code>. If the
  server does not support the requested version, it MUST return an <a href="#unsupportedprotocolversionerror" class="tsd-kind-interface">UnsupportedProtocolVersionError</a>.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="requestmetaobject-iomodelcontextprotocolclientinfo" data-typedoc-h="3"><span>"io.modelcontextprotocol/clientInfo"?: Implementation</span><a href="#requestmetaobject-iomodelcontextprotocolclientinfo" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Identifies the client software making the request. Clients SHOULD
  include this field on every request unless specifically configured not
  to do so.</p> <p>The <a href="#implementation" class="tsd-kind-interface">Implementation</a> schema requires <code>name</code> and <code>version</code>; other
  fields are optional.</p> <p>The value is self-reported by the client and is not verified by the
  protocol. It is intended for display, logging, and debugging. Servers
  SHOULD NOT use it to change their behavior, and SHOULD NOT rely on it for
  security decisions.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="requestmetaobject-iomodelcontextprotocolclientcapabilities" data-typedoc-h="3"><span>"io.modelcontextprotocol/clientCapabilities": ClientCapabilities</span><a href="#requestmetaobject-iomodelcontextprotocolclientcapabilities" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>The client's capabilities for this specific request. Required.</p> <p>Capabilities are declared per-request rather than once at initialization;
  an empty object means the client supports no optional capabilities.
  Servers MUST NOT infer capabilities from prior requests.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="requestmetaobject-iomodelcontextprotocolloglevel" data-typedoc-h="3"><span class="deprecated">"io.modelcontextprotocol/logLevel"?: LoggingLevel</span><a href="#requestmetaobject-iomodelcontextprotocolloglevel" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>The desired log level for this request. Optional.</p> <p>If absent, the server MUST NOT send any <a href="#loggingmessagenotification" class="tsd-kind-interface">notifications/message</a>
  notifications for this request. The client opts in to log messages by
  explicitly setting a level. Replaces the former <code>logging/setLevel</code> RPC.</p> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-deprecated"> <div class="tsd-anchor-link" data-typedoc-h="4">Deprecated</div><p>Deprecated as of protocol version 2026-07-28 (SEP-2577).
  Remains in the specification for at least twelve months; see the
  deprecated features registry.</p> </div></div></section>
</div>

<div class="type">
  ### `RequestParams`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">RequestParams</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#requestparams-_meta">\_meta</a><span class="tsd-signature-symbol">:</span> <a href="#requestmetaobject" class="tsd-signature-type tsd-kind-interface">RequestMetaObject</a><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Common params for any request.</p> </div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="requestparams-_meta" data-typedoc-h="3"><span>\_meta: RequestMetaObject</span><a href="#requestparams-_meta" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section>
</div>

<div class="type">
  ### `Result`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">Result</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#result-_meta">\_meta</a><span class="tsd-signature-symbol">?:</span> <a href="#resultmetaobject" class="tsd-signature-type tsd-kind-interface">ResultMetaObject</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#result-resulttype">resultType</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <span class="tsd-signature-symbol">\[</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Common result fields.</p> </div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="result-_meta" data-typedoc-h="3"><span>\_meta?: ResultMetaObject</span><a href="#result-_meta" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="result-resulttype" data-typedoc-h="3"><span>resultType: string</span><a href="#result-resulttype" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Indicates the type of the result, which allows the client to determine
  how to parse the result object.</p> <p>Servers implementing this protocol version MUST include this field.
  For backward compatibility, when a client receives a result from a
  server implementing an earlier protocol version (which does not include <code>resultType</code>), the client MUST treat the absent field as <code>"complete"</code>.</p> </div></section>
</div>

<div class="type">
  ### `ResultMetaObject`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">ResultMetaObject</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#resultmetaobject-iomodelcontextprotocolserverinfo">"io.modelcontextprotocol/serverInfo"</a><span class="tsd-signature-symbol">?:</span> <a href="#implementation" class="tsd-signature-type tsd-kind-interface">Implementation</a><span class="tsd-signature-symbol">;</span><br />  <span class="tsd-signature-symbol">\[</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Extends <a href="#metaobject" class="tsd-kind-type-alias">MetaObject</a> with additional result-specific fields. All key naming rules from <code>MetaObject</code> apply.</p> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-see"> <div class="tsd-anchor-link" data-typedoc-h="4">See</div><ul> <li><a href="#metaobject" class="tsd-kind-type-alias">MetaObject</a> for key naming rules and reserved prefixes.</li> <li><a href="/specification/2026-07-28/basic/index#meta">General fields: <code>\_meta</code></a> for more details.</li> </ul> </div></div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="resultmetaobject-iomodelcontextprotocolserverinfo" data-typedoc-h="3"><span>"io.modelcontextprotocol/serverInfo"?: Implementation</span><a href="#resultmetaobject-iomodelcontextprotocolserverinfo" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Identifies the server software producing the response. Servers SHOULD
  include this field on every response unless specifically configured not
  to do so.</p> <p>The <a href="#implementation" class="tsd-kind-interface">Implementation</a> schema requires <code>name</code> and <code>version</code>; other
  fields are optional.</p> <p>The value is self-reported by the server and is not verified by the
  protocol. It is intended for display, logging, and debugging. Clients
  SHOULD NOT use it to change their behavior, and SHOULD NOT rely on it for
  security decisions.</p> </div></section>
</div>

<div class="type">
  ### `ResultType`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">ResultType</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">"complete"</span> <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"input\_required"</span> <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">string</span></div> <div class="tsd-comment tsd-typography"><p>Indicates the type of a <a href="#result" class="tsd-kind-interface">Result</a> object, allowing the client to
  determine how to parse the response.</p> <p>complete - the request completed successfully and the result contains the final content.
  input\_required - the request requires additional input and the result contains an <a href="#inputrequiredresult" class="tsd-kind-interface">InputRequiredResult</a> object with instructions for the client to provide additional input before retrying the original request.</p> </div>
</div>

<div class="type">
  ### `Role`

  <div class="tsd-signature"><span class="tsd-kind-type-alias">Role</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">"user"</span> <span class="tsd-signature-symbol">|</span> <span class="tsd-signature-type">"assistant"</span></div> <div class="tsd-comment tsd-typography"><p>The sender or recipient of messages and data in a conversation.</p> </div>
</div>

## Errors

<div class="type">
  ### `Error`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">Error</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#error-code">code</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">number</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#error-message">message</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#error-data">data</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="error-code" data-typedoc-h="3"><span>code: number</span><a href="#error-code" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>The error type that occurred.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="error-message" data-typedoc-h="3"><span>message: string</span><a href="#error-message" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>A short description of the error. The message SHOULD be limited to a concise single sentence.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="error-data" data-typedoc-h="3"><span>data?: unknown</span><a href="#error-data" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Additional information about the error. The value of this member is defined by the sender (e.g. detailed error information, nested errors etc.).</p> </div></section>
</div>

<div class="type">
  ### `HEADER_MISMATCH`

  <div class="tsd-signature"><span class="tsd-kind-variable">HEADER\_MISMATCH</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32020</span></div> <div class="tsd-comment tsd-typography"><p>Error code returned when the HTTP headers of a request do not match the
  corresponding values in the request body, or required headers are
  missing or malformed.</p> </div>
</div>

<div class="type">
  ### `HeaderMismatchError`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">HeaderMismatchError</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#headermismatcherror-jsonrpc">jsonrpc</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">"2.0"</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#headermismatcherror-id">id</a><span class="tsd-signature-symbol">?:</span> <a href="#requestid" class="tsd-signature-type tsd-kind-type-alias">RequestId</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#headermismatcherror-error">error</a><span class="tsd-signature-symbol">:</span> <a href="#error" class="tsd-signature-type tsd-kind-interface">Error</a> <span class="tsd-signature-symbol">&</span> <span class="tsd-signature-symbol">\{</span> <span class="tsd-kind-property">code</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32020</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Returned when a server rejects a request because the values in the HTTP
  headers do not match the corresponding values in the request body, or
  because required headers are missing or malformed. For HTTP, the response
  status code MUST be <code>400 Bad Request</code>.</p> </div> <div class="tsd-comment tsd-typography"> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: Header mismatch<a href="#headermismatcherror-example-header-mismatch" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="headermismatcherror-example-header-mismatch"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"jsonrpc"</span><span class="hl-0">: </span><span class="hl-2">"2.0"</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"id"</span><span class="hl-0">: </span><span class="hl-3">1</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"error"</span><span class="hl-0">: \{</span><br /><span class="hl-0">    </span><span class="hl-1">"code"</span><span class="hl-0">: </span><span class="hl-3">-32020</span><span class="hl-0">,</span><br /><span class="hl-0">    </span><span class="hl-1">"message"</span><span class="hl-0">: </span><span class="hl-2">"Header mismatch: Mcp-Name header value 'foo' does not match body value 'bar'"</span><br /><span class="hl-0">  }</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="headermismatcherror-jsonrpc" data-typedoc-h="3"><span>jsonrpc: "2.0"</span><a href="#headermismatcherror-jsonrpc" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from <a href="#jsonrpcerrorresponse">JSONRPCErrorResponse</a>.<a href="#jsonrpcerrorresponse-jsonrpc">jsonrpc</a></p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="headermismatcherror-id" data-typedoc-h="3"><span>id?: RequestId</span><a href="#headermismatcherror-id" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from <a href="#jsonrpcerrorresponse">JSONRPCErrorResponse</a>.<a href="#jsonrpcerrorresponse-id">id</a></p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="headermismatcherror-error" data-typedoc-h="3"><span>error: Error & \{ code: -32020 }</span><a href="#headermismatcherror-error" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section>
</div>

<div class="type">
  ### `InternalError`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">InternalError</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#internalerror-message">message</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#internalerror-data">data</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#internalerror-code">code</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32603</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>A JSON-RPC error indicating that an internal error occurred on the receiver. This error is returned when the receiver encounters an unexpected condition that prevents it from fulfilling the request.</p> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-see"> <div class="tsd-anchor-link" data-typedoc-h="4">See</div><p><a href="https://www.jsonrpc.org/specification#error_object">JSON-RPC 2.0 Error Object</a></p> </div> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: Unexpected error<a href="#internalerror-example-unexpected-error" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="internalerror-example-unexpected-error"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"code"</span><span class="hl-0">: </span><span class="hl-3">-32603</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"message"</span><span class="hl-0">: </span><span class="hl-2">"Internal error"</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="internalerror-message" data-typedoc-h="3"><span>message: string</span><a href="#internalerror-message" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>A short description of the error. The message SHOULD be limited to a concise single sentence.</p> </div><aside class="tsd-sources"> <p>Inherited from <a href="#error">Error</a>.<a href="#error-message">message</a></p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="internalerror-data" data-typedoc-h="3"><span>data?: unknown</span><a href="#internalerror-data" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Additional information about the error. The value of this member is defined by the sender (e.g. detailed error information, nested errors etc.).</p> </div><aside class="tsd-sources"> <p>Inherited from <a href="#error">Error</a>.<a href="#error-data">data</a></p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="internalerror-code" data-typedoc-h="3"><span>code: -32603</span><a href="#internalerror-code" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>The error type that occurred.</p> </div><aside class="tsd-sources"> <p>Overrides <a href="#error">Error</a>.<a href="#error-code">code</a></p></aside></section>
</div>

<div class="type">
  ### `InvalidParamsError`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">InvalidParamsError</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#invalidparamserror-message">message</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#invalidparamserror-data">data</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#invalidparamserror-code">code</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32602</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>A JSON-RPC error indicating that the method parameters are invalid or malformed.</p> <p>In MCP, this error is returned in various contexts when request parameters fail validation:</p> <ul> <li><strong>Tools</strong>: Unknown tool name or invalid tool arguments</li> <li><strong>Prompts</strong>: Unknown prompt name or missing required arguments</li> <li><strong>Pagination</strong>: Invalid or expired cursor values</li> <li><strong>Logging</strong>: Invalid log level</li> <li><strong>Elicitation</strong>: Server requests an elicitation mode not declared in client capabilities</li> <li><strong>Sampling</strong>: Missing tool result or tool results mixed with other content</li> </ul> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-see"> <div class="tsd-anchor-link" data-typedoc-h="4">See</div><p><a href="https://www.jsonrpc.org/specification#error_object">JSON-RPC 2.0 Error Object</a></p> </div> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: Unknown tool<a href="#invalidparamserror-example-unknown-tool" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="invalidparamserror-example-unknown-tool"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"code"</span><span class="hl-0">: </span><span class="hl-3">-32602</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"message"</span><span class="hl-0">: </span><span class="hl-2">"Unknown tool: invalid\_tool\_name"</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: Invalid tool arguments<a href="#invalidparamserror-example-invalid-tool-arguments" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="invalidparamserror-example-invalid-tool-arguments"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"code"</span><span class="hl-0">: </span><span class="hl-3">-32602</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"message"</span><span class="hl-0">: </span><span class="hl-2">"Invalid arguments for tool calculate: Missing required property 'expression'"</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: Unknown prompt<a href="#invalidparamserror-example-unknown-prompt" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="invalidparamserror-example-unknown-prompt"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"code"</span><span class="hl-0">: </span><span class="hl-3">-32602</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"message"</span><span class="hl-0">: </span><span class="hl-2">"Unknown prompt: invalid\_prompt\_name"</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: Invalid cursor<a href="#invalidparamserror-example-invalid-cursor" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="invalidparamserror-example-invalid-cursor"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"code"</span><span class="hl-0">: </span><span class="hl-3">-32602</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"message"</span><span class="hl-0">: </span><span class="hl-2">"Invalid cursor"</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="invalidparamserror-message" data-typedoc-h="3"><span>message: string</span><a href="#invalidparamserror-message" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>A short description of the error. The message SHOULD be limited to a concise single sentence.</p> </div><aside class="tsd-sources"> <p>Inherited from <a href="#error">Error</a>.<a href="#error-message">message</a></p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="invalidparamserror-data" data-typedoc-h="3"><span>data?: unknown</span><a href="#invalidparamserror-data" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Additional information about the error. The value of this member is defined by the sender (e.g. detailed error information, nested errors etc.).</p> </div><aside class="tsd-sources"> <p>Inherited from <a href="#error">Error</a>.<a href="#error-data">data</a></p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="invalidparamserror-code" data-typedoc-h="3"><span>code: -32602</span><a href="#invalidparamserror-code" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>The error type that occurred.</p> </div><aside class="tsd-sources"> <p>Overrides <a href="#error">Error</a>.<a href="#error-code">code</a></p></aside></section>
</div>

<div class="type">
  ### `InvalidRequestError`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">InvalidRequestError</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#invalidrequesterror-message">message</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#invalidrequesterror-data">data</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#invalidrequesterror-code">code</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32600</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>A JSON-RPC error indicating that the request is not a valid request object. This error is returned when the message structure does not conform to the JSON-RPC 2.0 specification requirements for a request (e.g., missing required fields like <code>jsonrpc</code> or <code>method</code>, or using invalid types for these fields).</p> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-see"> <div class="tsd-anchor-link" data-typedoc-h="4">See</div><p><a href="https://www.jsonrpc.org/specification#error_object">JSON-RPC 2.0 Error Object</a></p> </div></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="invalidrequesterror-message" data-typedoc-h="3"><span>message: string</span><a href="#invalidrequesterror-message" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>A short description of the error. The message SHOULD be limited to a concise single sentence.</p> </div><aside class="tsd-sources"> <p>Inherited from <a href="#error">Error</a>.<a href="#error-message">message</a></p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="invalidrequesterror-data" data-typedoc-h="3"><span>data?: unknown</span><a href="#invalidrequesterror-data" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Additional information about the error. The value of this member is defined by the sender (e.g. detailed error information, nested errors etc.).</p> </div><aside class="tsd-sources"> <p>Inherited from <a href="#error">Error</a>.<a href="#error-data">data</a></p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="invalidrequesterror-code" data-typedoc-h="3"><span>code: -32600</span><a href="#invalidrequesterror-code" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>The error type that occurred.</p> </div><aside class="tsd-sources"> <p>Overrides <a href="#error">Error</a>.<a href="#error-code">code</a></p></aside></section>
</div>

<div class="type">
  ### `MethodNotFoundError`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">MethodNotFoundError</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#methodnotfounderror-message">message</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#methodnotfounderror-data">data</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#methodnotfounderror-code">code</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32601</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>A JSON-RPC error indicating that the requested method does not exist or is not available.</p> <p>In MCP, a server returns this error when a client invokes a method the server does not implement — either a genuinely unknown method, or one gated behind a server capability the server did not advertise (e.g., calling <code>prompts/list</code> when the <code>prompts</code> capability was not advertised).</p> <p>A request that requires a client capability the client did not declare is signalled instead by <a href="#missingrequiredclientcapabilityerror" class="tsd-kind-interface">MissingRequiredClientCapabilityError</a> (<code>-32021</code>).</p> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-see"> <div class="tsd-anchor-link" data-typedoc-h="4">See</div><p><a href="https://www.jsonrpc.org/specification#error_object">JSON-RPC 2.0 Error Object</a></p> </div> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: Prompts not supported<a href="#methodnotfounderror-example-prompts-not-supported" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="methodnotfounderror-example-prompts-not-supported"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"code"</span><span class="hl-0">: </span><span class="hl-3">-32601</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"message"</span><span class="hl-0">: </span><span class="hl-2">"Prompts not supported"</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"data"</span><span class="hl-0">: \{</span><br /><span class="hl-0">    </span><span class="hl-1">"reason"</span><span class="hl-0">: </span><span class="hl-2">"Server does not support the prompts capability"</span><br /><span class="hl-0">  }</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="methodnotfounderror-message" data-typedoc-h="3"><span>message: string</span><a href="#methodnotfounderror-message" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>A short description of the error. The message SHOULD be limited to a concise single sentence.</p> </div><aside class="tsd-sources"> <p>Inherited from <a href="#error">Error</a>.<a href="#error-message">message</a></p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="methodnotfounderror-data" data-typedoc-h="3"><span>data?: unknown</span><a href="#methodnotfounderror-data" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Additional information about the error. The value of this member is defined by the sender (e.g. detailed error information, nested errors etc.).</p> </div><aside class="tsd-sources"> <p>Inherited from <a href="#error">Error</a>.<a href="#error-data">data</a></p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="methodnotfounderror-code" data-typedoc-h="3"><span>code: -32601</span><a href="#methodnotfounderror-code" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>The error type that occurred.</p> </div><aside class="tsd-sources"> <p>Overrides <a href="#error">Error</a>.<a href="#error-code">code</a></p></aside></section>
</div>

<div class="type">
  ### `MISSING_REQUIRED_CLIENT_CAPABILITY`

  <div class="tsd-signature"><span class="tsd-kind-variable">MISSING\_REQUIRED\_CLIENT\_CAPABILITY</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32021</span></div> <div class="tsd-comment tsd-typography"><p>Error code returned when a server requires a client capability that was
  not declared in the request's <code>clientCapabilities</code>.</p> </div>
</div>

<div class="type">
  ### `MissingRequiredClientCapabilityError`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">MissingRequiredClientCapabilityError</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#missingrequiredclientcapabilityerror-jsonrpc">jsonrpc</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">"2.0"</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#missingrequiredclientcapabilityerror-id">id</a><span class="tsd-signature-symbol">?:</span> <a href="#requestid" class="tsd-signature-type tsd-kind-type-alias">RequestId</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#missingrequiredclientcapabilityerror-error">error</a><span class="tsd-signature-symbol">:</span> <a href="#error" class="tsd-signature-type tsd-kind-interface">Error</a> <span class="tsd-signature-symbol">&</span> <span class="tsd-signature-symbol">\{</span><br />    <span class="tsd-kind-property">code</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32021</span><span class="tsd-signature-symbol">;</span><br />    <span class="tsd-kind-property">data</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-symbol">\{</span> <span class="tsd-kind-property">requiredCapabilities</span><span class="tsd-signature-symbol">:</span> <a href="#clientcapabilities" class="tsd-signature-type tsd-kind-interface">ClientCapabilities</a> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br />  <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Returned when processing a request requires a capability the client did not
  declare in <code>clientCapabilities</code>. For HTTP, the response status code MUST be <code>400 Bad Request</code>.</p> </div> <div class="tsd-comment tsd-typography"> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: Missing elicitation capability<a href="#missingrequiredclientcapabilityerror-example-missing-elicitation-capability" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="missingrequiredclientcapabilityerror-example-missing-elicitation-capability"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"jsonrpc"</span><span class="hl-0">: </span><span class="hl-2">"2.0"</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"id"</span><span class="hl-0">: </span><span class="hl-3">1</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"error"</span><span class="hl-0">: \{</span><br /><span class="hl-0">    </span><span class="hl-1">"code"</span><span class="hl-0">: </span><span class="hl-3">-32021</span><span class="hl-0">,</span><br /><span class="hl-0">    </span><span class="hl-1">"message"</span><span class="hl-0">: </span><span class="hl-2">"Server requires the elicitation capability for this request"</span><span class="hl-0">,</span><br /><span class="hl-0">    </span><span class="hl-1">"data"</span><span class="hl-0">: \{</span><br /><span class="hl-0">      </span><span class="hl-1">"requiredCapabilities"</span><span class="hl-0">: \{</span><br /><span class="hl-0">        </span><span class="hl-1">"elicitation"</span><span class="hl-0">: \{}</span><br /><span class="hl-0">      }</span><br /><span class="hl-0">    }</span><br /><span class="hl-0">  }</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="missingrequiredclientcapabilityerror-jsonrpc" data-typedoc-h="3"><span>jsonrpc: "2.0"</span><a href="#missingrequiredclientcapabilityerror-jsonrpc" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from <a href="#jsonrpcerrorresponse">JSONRPCErrorResponse</a>.<a href="#jsonrpcerrorresponse-jsonrpc">jsonrpc</a></p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="missingrequiredclientcapabilityerror-id" data-typedoc-h="3"><span>id?: RequestId</span><a href="#missingrequiredclientcapabilityerror-id" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from <a href="#jsonrpcerrorresponse">JSONRPCErrorResponse</a>.<a href="#jsonrpcerrorresponse-id">id</a></p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="missingrequiredclientcapabilityerror-error" data-typedoc-h="3"><span>error: Error & \{    code: -32021;    data: \{ requiredCapabilities: ClientCapabilities }; }</span><a href="#missingrequiredclientcapabilityerror-error" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section>
</div>

<div class="type">
  ### `ParseError`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">ParseError</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#parseerror-message">message</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#parseerror-data">data</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">unknown</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#parseerror-code">code</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32700</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>A JSON-RPC error indicating that invalid JSON was received by the server. This error is returned when the server cannot parse the JSON text of a message.</p> </div> <div class="tsd-comment tsd-typography"> <div class="tsd-tag-see"> <div class="tsd-anchor-link" data-typedoc-h="4">See</div><p><a href="https://www.jsonrpc.org/specification#error_object">JSON-RPC 2.0 Error Object</a></p> </div> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: Invalid JSON<a href="#parseerror-example-invalid-json" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="parseerror-example-invalid-json"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"code"</span><span class="hl-0">: </span><span class="hl-3">-32700</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"message"</span><span class="hl-0">: </span><span class="hl-2">"Parse error: Invalid JSON"</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="parseerror-message" data-typedoc-h="3"><span>message: string</span><a href="#parseerror-message" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>A short description of the error. The message SHOULD be limited to a concise single sentence.</p> </div><aside class="tsd-sources"> <p>Inherited from <a href="#error">Error</a>.<a href="#error-message">message</a></p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="parseerror-data" data-typedoc-h="3"><span>data?: unknown</span><a href="#parseerror-data" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>Additional information about the error. The value of this member is defined by the sender (e.g. detailed error information, nested errors etc.).</p> </div><aside class="tsd-sources"> <p>Inherited from <a href="#error">Error</a>.<a href="#error-data">data</a></p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="parseerror-code" data-typedoc-h="3"><span>code: -32700</span><a href="#parseerror-code" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <div class="tsd-comment tsd-typography"><p>The error type that occurred.</p> </div><aside class="tsd-sources"> <p>Overrides <a href="#error">Error</a>.<a href="#error-code">code</a></p></aside></section>
</div>

<div class="type">
  ### `UNSUPPORTED_PROTOCOL_VERSION`

  <div class="tsd-signature"><span class="tsd-kind-variable">UNSUPPORTED\_PROTOCOL\_VERSION</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32022</span></div> <div class="tsd-comment tsd-typography"><p>Error code returned when the request's protocol version is not supported
  by the server.</p> </div>
</div>

<div class="type">
  ### `UnsupportedProtocolVersionError`

  <div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">UnsupportedProtocolVersionError</span> <span class="tsd-signature-symbol">\{</span><br />  <a class="tsd-kind-property" href="#unsupportedprotocolversionerror-jsonrpc">jsonrpc</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">"2.0"</span><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#unsupportedprotocolversionerror-id">id</a><span class="tsd-signature-symbol">?:</span> <a href="#requestid" class="tsd-signature-type tsd-kind-type-alias">RequestId</a><span class="tsd-signature-symbol">;</span><br />  <a class="tsd-kind-property" href="#unsupportedprotocolversionerror-error">error</a><span class="tsd-signature-symbol">:</span> <a href="#error" class="tsd-signature-type tsd-kind-interface">Error</a> <span class="tsd-signature-symbol">&</span> <span class="tsd-signature-symbol">\{</span><br />    <span class="tsd-kind-property">code</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">-32022</span><span class="tsd-signature-symbol">;</span><br />    <span class="tsd-kind-property">data</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-symbol">\{</span> <span class="tsd-kind-property">supported</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">\[]</span><span class="tsd-signature-symbol">;</span> <span class="tsd-kind-property">requested</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br />  <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br /><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Returned when the request's protocol version is unknown to the server or
  unsupported (e.g., a known experimental or draft version the server has
  chosen not to implement). For HTTP, the response status code MUST be <code>400 Bad Request</code>.</p> </div> <div class="tsd-comment tsd-typography"> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: Unsupported protocol version<a href="#unsupportedprotocolversionerror-example-unsupported-protocol-version" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></summary><pre id="unsupportedprotocolversionerror-example-unsupported-protocol-version"><code class="json"><span class="hl-0">\{</span><br /><span class="hl-0">  </span><span class="hl-1">"jsonrpc"</span><span class="hl-0">: </span><span class="hl-2">"2.0"</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"id"</span><span class="hl-0">: </span><span class="hl-3">1</span><span class="hl-0">,</span><br /><span class="hl-0">  </span><span class="hl-1">"error"</span><span class="hl-0">: \{</span><br /><span class="hl-0">    </span><span class="hl-1">"code"</span><span class="hl-0">: </span><span class="hl-3">-32022</span><span class="hl-0">,</span><br /><span class="hl-0">    </span><span class="hl-1">"message"</span><span class="hl-0">: </span><span class="hl-2">"Unsupported protocol version"</span><span class="hl-0">,</span><br /><span class="hl-0">    </span><span class="hl-1">"data"</span><span class="hl-0">: \{</span><br /><span class="hl-0">      </span><span class="hl-1">"supported"</span><span class="hl-0">: \[</span><br /><span class="hl-0">        </span><span class="hl-2">"2026-07-28"</span><span class="hl-0">,</span><br /><span class="hl-0">        </span><span class="hl-2">"2025-11-25"</span><br /><span class="hl-0">      ],</span><br /><span class="hl-0">      </span><span class="hl-1">"requested"</span><span class="hl-0">: </span><span class="hl-2">"1900-01-01"</span><br /><span class="hl-0">    }</span><br /><span class="hl-0">  }</span><br /><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="unsupportedprotocolversionerror-jsonrpc" data-typedoc-h="3"><span>jsonrpc: "2.0"</span><a href="#unsupportedprotocolversionerror-jsonrpc" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from <a href="#jsonrpcerrorresponse">JSONRPCErrorResponse</a>.<a href="#jsonrpcerrorresponse-jsonrpc">jsonrpc</a></p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="unsupportedprotocolversionerror-id" data-typedoc-h="3"><span>id?: RequestId</span><a href="#unsupportedprotocolversionerror-id" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> <aside class="tsd-sources"> <p>Inherited from <a href="#jsonrpcerrorresponse">JSONRPCErrorResponse</a>.<a href="#jsonrpcerrorresponse-id">id</a></p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="unsupportedprotocolversionerror-error" data-typedoc-h="3"><span>error: Error & \{    code: -32022;    data: \{ supported: string\[]; requested: string }; }</span><a href="#unsupportedprotocolversionerror-error" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor" /></svg></a></div> </section>
</div>

## Content

<div class="type">

Cut at 300 lines.