feat: add MCP prompts support to useMcp hook

- Add Prompt type from MCP SDK
- Add prompts array to UseMcpResult
- Fetch prompts automatically after resources during connection
- Add listPrompts() method to manually refresh prompts list
- Add getPrompt(name, args) method to get specific prompt messages
- Clear prompts state on disconnect

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/react/types.ts

@@ -1,4 +1,4 @@
-import { Tool, Resource, ResourceTemplate } from '@modelcontextprotocol/sdk/types.js'
+import { Tool, Resource, ResourceTemplate, Prompt } from '@modelcontextprotocol/sdk/types.js'
 
 export type UseMcpOptions = {
   /** The /sse URL of your remote MCP server */
@@ -39,6 +39,8 @@ export type UseMcpResult = {
   resources: Resource[]
   /** List of resource templates available from the connected MCP server */
   resourceTemplates: ResourceTemplate[]
+  /** List of prompts available from the connected MCP server */
+  prompts: Prompt[]
   /**
    * The current state of the MCP connection:
    * - 'discovering': Checking server existence and capabilities (including auth requirements).
@@ -80,6 +82,23 @@ export type UseMcpResult = {
    * @throws If the client is not in the 'ready' state or the read fails.
    */
   readResource: (uri: string) => Promise<{ contents: Array<{ uri: string; mimeType?: string; text?: string; blob?: string }> }>
+  /**
+   * Function to list prompts from the MCP server.
+   * @returns A promise that resolves when prompts are refreshed.
+   * @throws If the client is not in the 'ready' state.
+   */
+  listPrompts: () => Promise<void>
+  /**
+   * Function to get a specific prompt from the MCP server.
+   * @param name The name of the prompt to get.
+   * @param args Optional arguments for the prompt.
+   * @returns A promise that resolves with the prompt messages.
+   * @throws If the client is not in the 'ready' state or the get fails.
+   */
+  getPrompt: (
+    name: string,
+    args?: Record<string, string>,
+  ) => Promise<{ messages: Array<{ role: 'user' | 'assistant'; content: { type: string; text?: string; [key: string]: any } }> }>
   /** Manually attempts to reconnect if the state is 'failed'. */
   retry: () => void
   /** Disconnects the client from the MCP server. */

src/react/useMcp.ts

@@ -5,9 +5,12 @@ import {
   ListToolsResultSchema,
   ListResourcesResultSchema,
   ReadResourceResultSchema,
+  ListPromptsResultSchema,
+  GetPromptResultSchema,
   Tool,
   Resource,
   ResourceTemplate,
+  Prompt,
 } from '@modelcontextprotocol/sdk/types.js'
 import { useCallback, useEffect, useRef, useState } from 'react'
 // Import both transport types
@@ -50,6 +53,7 @@ export function useMcp(options: UseMcpOptions): UseMcpResult {
   const [tools, setTools] = useState<Tool[]>([])
   const [resources, setResources] = useState<Resource[]>([])
   const [resourceTemplates, setResourceTemplates] = useState<ResourceTemplate[]>([])
+  const [prompts, setPrompts] = useState<Prompt[]>([])
   const [error, setError] = useState<string | undefined>(undefined)
   const [log, setLog] = useState<UseMcpResult['log']>([])
   const [authUrl, setAuthUrl] = useState<string | undefined>(undefined)
@@ -108,6 +112,7 @@ export function useMcp(options: UseMcpOptions): UseMcpResult {
         setTools([])
         setResources([])
         setResourceTemplates([])
+        setPrompts([])
         setError(undefined)
         setAuthUrl(undefined)
       }
@@ -296,7 +301,7 @@ export function useMcp(options: UseMcpOptions): UseMcpResult {
         await clientRef.current!.connect(transportInstance)
 
         // --- Success Path ---
-        addLog('info', `Client connected via ${transportType.toUpperCase()}. Loading tools and resources...`)
+        addLog('info', `Client connected via ${transportType.toUpperCase()}. Loading tools, resources, and prompts...`)
         successfulTransportRef.current = transportType // Store successful type
         setState('loading')
 
@@ -305,14 +310,18 @@ export function useMcp(options: UseMcpOptions): UseMcpResult {
         // Load resources after tools
         const resourcesResponse = await clientRef.current!.request({ method: 'resources/list' }, ListResourcesResultSchema)
 
+        // Load prompts after resources
+        const promptsResponse = await clientRef.current!.request({ method: 'prompts/list' }, ListPromptsResultSchema)
+
         if (isMountedRef.current) {
           // Check mount before final state updates
           setTools(toolsResponse.tools)
           setResources(resourcesResponse.resources)
           setResourceTemplates(Array.isArray(resourcesResponse.resourceTemplates) ? resourcesResponse.resourceTemplates : [])
+          setPrompts(promptsResponse.prompts)
           addLog(
             'info',
-            `Loaded ${toolsResponse.tools.length} tools, ${resourcesResponse.resources.length} resources, ${Array.isArray(resourcesResponse.resourceTemplates) ? resourcesResponse.resourceTemplates.length : 0} resource templates.`,
+            `Loaded ${toolsResponse.tools.length} tools, ${resourcesResponse.resources.length} resources, ${Array.isArray(resourcesResponse.resourceTemplates) ? resourcesResponse.resourceTemplates.length : 0} resource templates, ${promptsResponse.prompts.length} prompts.`,
           )
           setState('ready') // Final success state
           // connectingRef will be set to false after orchestration logic
@@ -668,6 +677,45 @@ export function useMcp(options: UseMcpOptions): UseMcpResult {
     [state, addLog],
   ) // Depends on state for error message and stable addLog
 
+  // listPrompts is stable (depends on stable addLog)
+  const listPrompts = useCallback(async () => {
+    // Use stateRef for check, state for throwing error message
+    if (stateRef.current !== 'ready' || !clientRef.current) {
+      throw new Error(`MCP client is not ready (current state: ${state}). Cannot list prompts.`)
+    }
+    addLog('info', 'Listing prompts...')
+    try {
+      const promptsResponse = await clientRef.current.request({ method: 'prompts/list' }, ListPromptsResultSchema)
+      if (isMountedRef.current) {
+        setPrompts(promptsResponse.prompts)
+        addLog('info', `Listed ${promptsResponse.prompts.length} prompts.`)
+      }
+    } catch (err) {
+      addLog('error', `Error listing prompts: ${err instanceof Error ? err.message : String(err)}`, err)
+      throw err
+    }
+  }, [state, addLog]) // Depends on state for error message and stable addLog
+
+  // getPrompt is stable (depends on stable addLog)
+  const getPrompt = useCallback(
+    async (name: string, args?: Record<string, string>) => {
+      // Use stateRef for check, state for throwing error message
+      if (stateRef.current !== 'ready' || !clientRef.current) {
+        throw new Error(`MCP client is not ready (current state: ${state}). Cannot get prompt "${name}".`)
+      }
+      addLog('info', `Getting prompt: ${name}`, args)
+      try {
+        const result = await clientRef.current.request({ method: 'prompts/get', params: { name, arguments: args } }, GetPromptResultSchema)
+        addLog('info', `Prompt "${name}" retrieved successfully`)
+        return result
+      } catch (err) {
+        addLog('error', `Error getting prompt "${name}": ${err instanceof Error ? err.message : String(err)}`, err)
+        throw err
+      }
+    },
+    [state, addLog],
+  ) // Depends on state for error message and stable addLog
+
   // ===== Effects =====
 
   // Effect for handling auth callback messages from popup (Stable dependencies)
@@ -757,12 +805,15 @@ export function useMcp(options: UseMcpOptions): UseMcpResult {
     tools,
     resources,
     resourceTemplates,
+    prompts,
     error,
     log,
     authUrl,
     callTool,
     listResources,
     readResource,
+    listPrompts,
+    getPrompt,
     retry,
     disconnect,
     authenticate,