狀態 MCP 伺服器功能
模型內容通訊協定 (MCP) 提供 AI 應用程式與外部資料和功能互動的標準化方式。本指南示範如何建置全面的 MCP 伺服器來展示所有主要通訊協定功能,以及如何在本機和部署到 Amazon Bedrock AgentCore 時進行測試。
如需完整的通訊協定詳細資訊,請參閱 MCP 規格
MCP 功能概觀
MCP 伺服器可以透過多種功能類型向用戶端公開功能。本指南示範了下列功能:
- 資源
-
資源會將資料和內容從伺服器公開至 MCP 用戶端。使用 資源來共用組態、參考資料或用戶端或 AI 模型可以讀取的任何內容資訊。資源由 URIs識別 (例如
travel://destinations,)。 - 提示
-
提示是可重複使用的範本,可產生 AI 模型的結構化訊息。使用提示來標準化常見的互動,例如產生目的地的包裝清單或學習本機片語。
- 工具
-
工具是 AI 模型可以叫用以執行動作或擷取資訊的函數。工具的範圍可以從簡單的資料查詢到結合其他 MCP 功能的複雜多步驟工作流程。
- 引出
-
Elicitation 會在工具執行期間為使用者輸入啟用伺服器起始的請求。當您的工具需要以互動方式收集資訊時,請使用引動,例如透過多迴轉對話收集行程偏好設定。
- 取樣
-
取樣可讓伺服器從用戶端請求 LLM 產生的內容。當您的工具需要 AI 驅動的文字產生時,請使用抽樣,例如根據使用者偏好設定的個人化行程建議。
- 進度通知
-
進度通知可讓用戶端了解長時間執行的操作。使用進度報告在搜尋航班或處理預訂等任務期間提供即時意見回饋。
注意
引出、取樣和進度通知等功能需要有狀態的 MCP 工作階段。在執行伺服器stateless_http=False時設定 以啟用狀態模式。
工作階段管理
在具狀態模式中,伺服器會在初始化呼叫期間傳回 Mcp-Session-Id標頭。用戶端必須在後續請求中包含此工作階段 ID,以維護工作階段內容。如果伺服器終止或工作階段過期,請求可能會傳回 404 錯誤,且用戶端必須重新初始化以取得新的工作階段 ID。如需詳細資訊,請參閱 MCP 規格中的工作階段管理
建立具有所有功能的 MCP 伺服器
設定專案
-
建立具有必要相依性
requirements.txt的檔案:fastmcp>=2.10.0 mcp -
安裝相依項:
pip install -r requirements.txt
travel_server.py 使用下列程式碼建立名為 的檔案。此旅行預訂代理程式會在逼真的工作流程中示範所有 MCP 功能:
""" Travel Booking Agent - Stateful MCP Server Demonstrates all MCP features in a real-world travel booking workflow: - Elicitation: Collect trip preferences interactively - Progress: Show search progress for flights and hotels - Sampling: AI-generated personalized recommendations - Resources: Expose destination data and pricing - Prompts: Templates for packing lists and local phrases """ import asyncio import json from fastmcp import FastMCP, Context from enum import Enum mcp = FastMCP("Travel-Booking-Agent") # ============================================================ # DATA # ============================================================ class TripType(str, Enum): BUSINESS = "business" LEISURE = "leisure" FAMILY = "family" DESTINATIONS = { "paris": {"name": "Paris, France", "flight": 450, "hotel": 180, "highlights": ["Eiffel Tower", "Louvre", "Notre-Dame"], "phrases": ["Bonjour", "Merci", "S'il vous plait"]}, "tokyo": {"name": "Tokyo, Japan", "flight": 900, "hotel": 150, "highlights": ["Shibuya", "Senso-ji Temple", "Mt. Fuji day trip"], "phrases": ["Konnichiwa", "Arigato", "Sumimasen"]}, "new york": {"name": "New York, USA", "flight": 350, "hotel": 250, "highlights": ["Central Park", "Broadway", "Statue of Liberty"], "phrases": ["Hey!", "Thanks", "Excuse me"]}, "bali": {"name": "Bali, Indonesia", "flight": 800, "hotel": 100, "highlights": ["Ubud Rice Terraces", "Tanah Lot", "Beach clubs"], "phrases": ["Selamat pagi", "Terima kasih", "Sama-sama"]} } # ============================================================ # RESOURCES - Expose data to MCP clients # ============================================================ @mcp.resource("travel://destinations") def list_destinations() -> str: """All available destinations with pricing.""" return json.dumps({k: {"name": v["name"], "flight": v["flight"], "hotel": v["hotel"]} for k, v in DESTINATIONS.items()}, indent=2) @mcp.resource("travel://destination/{city}") def get_destination(city: str) -> str: """Detailed info for a specific destination.""" dest = DESTINATIONS.get(city.lower()) return json.dumps(dest, indent=2) if dest else f"Unknown: {city}" # ============================================================ # PROMPTS - Reusable templates for AI generation # ============================================================ @mcp.prompt() def packing_list(destination: str, days: int, trip_type: str) -> str: """Generate packing list prompt.""" return f"Create a {days}-day packing list for a {trip_type} trip to {destination}. Be practical and concise." @mcp.prompt() def local_phrases(destination: str) -> str: """Generate local phrases prompt.""" dest = DESTINATIONS.get(destination.lower(), {}) phrases = dest.get("phrases", []) return f"Teach me essential phrases for {destination}. Start with: {', '.join(phrases)}" # ============================================================ # MAIN TOOL - Complete booking with all MCP features # ============================================================ @mcp.tool() async def plan_trip(ctx: Context) -> str: """ Plan a complete trip using all MCP features: 1. Elicitation - Collect preferences 2. Progress - Search flights and hotels 3. Sampling - AI recommendations """ # -------- PHASE 1: ELICITATION -------- # Collect trip details through multi-turn conversation dest_result = await ctx.elicit( message="Where would you like to go?\nOptions: Paris, Tokyo, New York, Bali", response_type=str ) if dest_result.action != "accept": return "Trip planning cancelled." dest_key = dest_result.data.lower().strip() dest = DESTINATIONS.get(dest_key, DESTINATIONS["paris"]) type_result = await ctx.elicit( message="What type of trip?\n1. business\n2. leisure\n3. family", response_type=TripType ) if type_result.action != "accept": return "Trip planning cancelled." trip_type = type_result.data days_result = await ctx.elicit( message="How many days? (3-14)", response_type=int ) if days_result.action != "accept": return "Trip planning cancelled." days = max(3, min(14, days_result.data)) travelers_result = await ctx.elicit( message="Number of travelers?", response_type=int ) if travelers_result.action != "accept": return "Trip planning cancelled." travelers = travelers_result.data # -------- PHASE 2: PROGRESS NOTIFICATIONS -------- # Search for flights and hotels with progress updates total_steps = 5 await ctx.report_progress(progress=1, total=total_steps) # Searching flights await asyncio.sleep(0.4) await ctx.report_progress(progress=2, total=total_steps) # Comparing airlines await asyncio.sleep(0.4) await ctx.report_progress(progress=3, total=total_steps) # Searching hotels await asyncio.sleep(0.4) await ctx.report_progress(progress=4, total=total_steps) # Checking availability await asyncio.sleep(0.4) await ctx.report_progress(progress=5, total=total_steps) # Finalizing await asyncio.sleep(0.2) # Calculate costs flight_cost = dest["flight"] * travelers hotel_cost = dest["hotel"] * days * ((travelers + 1) // 2) # Rooms needed total_cost = flight_cost + hotel_cost # -------- PHASE 3: SAMPLING -------- # Get AI-generated personalized recommendations ai_tips = f"Enjoy {dest['name']}!" try: response = await ctx.sample( messages=f"Give 3 brief tips for a {trip_type} trip to {dest['name']} for {travelers} travelers, {days} days. Max 60 words.", max_tokens=150 ) if hasattr(response, 'text') and response.text: ai_tips = response.text except Exception: ai_tips = f"Visit {dest['highlights'][0]}, try local food, learn basic phrases!" # -------- FINAL CONFIRMATION -------- confirm = await ctx.elicit( message=f""" ========== TRIP SUMMARY ========== Destination: {dest['name']} Trip Type: {trip_type} Duration: {days} days Travelers: {travelers} COSTS: Flights: ${flight_cost} Hotels: ${hotel_cost} ({(travelers + 1) // 2} room(s) x {days} nights) TOTAL: ${total_cost} Confirm booking? (Yes/No)""", response_type=["Yes", "No"] ) if confirm.action != "accept" or confirm.data == "No": return "Booking cancelled. Your search results are saved for 24 hours." # -------- FINAL RESULT -------- highlights_str = '\n'.join(f' * {h}' for h in dest['highlights']) phrases_str = '\n'.join(f' * {p}' for p in dest['phrases']) return f""" {'=' * 50} BOOKING CONFIRMED! {'=' * 50} Booking Reference: TRV-{ctx.session_id[:8].upper()} TRIP DETAILS: {dest['name']} {days} days | {travelers} traveler(s) Trip type: {trip_type} FLIGHTS: ${flight_cost} Outbound: Day 1, Morning departure Return: Day {days}, Evening departure ACCOMMODATION: ${hotel_cost} {(travelers + 1) // 2} room(s) for {days} nights TOTAL PAID: ${total_cost} HIGHLIGHTS TO EXPLORE: {highlights_str} USEFUL PHRASES: {phrases_str} AI RECOMMENDATIONS: {ai_tips} {'=' * 50} Thank you for booking with Travel Agent! """ if __name__ == "__main__": print("=" * 60) print(" Travel Booking Agent - Stateful MCP Server") print("=" * 60) print("\n MCP FEATURES DEMONSTRATED:") print(" * Elicitation - Multi-turn trip preference collection") print(" * Progress - Real-time search progress updates") print(" * Sampling - AI-powered travel recommendations") print(" * Resources - Destination data and pricing") print(" * Prompts - Packing list and phrase templates") print("\n TOOLS:") print(" plan_trip - Complete booking flow with all features") print("\n RESOURCES:") print(" travel://destinations - All destinations") print(" travel://destination/{city} - City details") print("\n PROMPTS:") print(" packing_list - Generate packing suggestions") print(" local_phrases - Learn useful phrases") print("\n" + "=" * 60) print(f" Server: http://0.0.0.0:8000/mcp") print("=" * 60) mcp.run( transport="streamable-http", host="0.0.0.0", port=8000, stateless_http=False )
本機測試
啟動伺服器
-
執行 MCP 伺服器:
python travel_server.py您應該會看到輸出,指出伺服器正在連接埠 8000 上執行。
test_client.py 使用下列程式碼建立名為 的檔案。此用戶端會測試所有 MCP 功能,包括資源、提示和主要工具:
""" Travel Booking Agent - Test Client Tests all MCP features: Elicitation, Sampling, Progress, Resources, Prompts """ import asyncio import os import sys from fastmcp import Client from fastmcp.client.transports import StreamableHttpTransport from fastmcp.client.elicitation import ElicitResult from mcp.types import CreateMessageResult, TextContent async def elicit_handler(message: str, response_type, params, ctx): """Handle elicitation - interactive input.""" print(f"\n>>> Server asks: {message}") if isinstance(response_type, list): for i, opt in enumerate(response_type, 1): print(f" {i}. {opt}") choice = input(" Your choice (number): ").strip() response = response_type[int(choice) - 1] else: hint = " (number)" if response_type == int else "" response = input(f" Your answer{hint}: ").strip() if response_type == int: response = int(response) print(f"<<< Responding: {response}") return ElicitResult(action="accept", content={"value": response}) async def sampling_handler(messages, params, ctx): """Handle sampling - provide LLM response.""" print(f"\n>>> AI Sampling Request") prompt = messages if isinstance(messages, str) else str(messages) print(f" Prompt: {prompt[:80]}...") user_input = input(" Enter AI response (or Enter for auto): ").strip() if not user_input: user_input = "1. Book popular attractions early. 2. Try local street food. 3. Learn basic greetings!" print(f"<<< AI Response: {user_input}") return CreateMessageResult( role="assistant", content=TextContent(type="text", text=user_input), model="test-model", stopReason="endTurn" ) async def progress_handler(progress: float, total: float | None, message: str | None): """Handle progress notifications.""" pct = int((progress / total) * 100) if total else 0 bar = "#" * (pct // 5) + "-" * (20 - pct // 5) print(f"\r Progress: [{bar}] {pct}% ({int(progress)}/{int(total or 0)})", end="", flush=True) if progress == total: print(" Done!") async def main(): local_test = os.getenv('LOCAL_TEST', 'true').lower() == 'true' if local_test: url = sys.argv[1] if len(sys.argv) > 1 else "http://localhost:8000/mcp" token = None else: agent_arn = os.getenv('AGENT_ARN') if not agent_arn: print("ERROR: Missing AGENT_ARN environment variable") sys.exit(1) encoded_arn = agent_arn.replace(':', '%3A').replace('/', '%2F') endpoint = os.getenv('MCP_ENDPOINT', 'https://bedrock-agentcore.us-west-2.amazonaws.com') url = f"{endpoint}/runtimes/{encoded_arn}/invocations?qualifier=DEFAULT" token = os.getenv('BEARER_TOKEN') if not token: print("ERROR: Missing BEARER_TOKEN for remote testing") sys.exit(1) print(f" Agent ARN: {agent_arn}") print(f" Endpoint: {endpoint}") print("=" * 60) print(" Travel Agent - MCP Feature Test Client") print("=" * 60) headers = {} if token: headers["Authorization"] = f"Bearer {token}" print(f" Using auth token (len={len(token)})") transport = StreamableHttpTransport(url=url, headers=headers) client = Client( transport, elicitation_handler=elicit_handler, sampling_handler=sampling_handler, progress_handler=progress_handler ) try: await client.__aenter__() # Test Resources print("\n[1] Testing RESOURCES...") resources = await client.list_resources() print(f" Found {len(resources)} resource(s)") # Test Prompts print("\n[2] Testing PROMPTS...") prompts = await client.list_prompts() print(f" Found {len(prompts)} prompt(s)") # Test Main Tool (Elicitation + Progress + Sampling) print("\n[3] Testing PLAN_TRIP tool...") print(" (This tests Elicitation, Progress, and Sampling)\n") result = await client.call_tool("plan_trip", {}) print("\n" + "=" * 60) print("RESULT:") print("=" * 60) print(result.content[0].text) print("=" * 60) print(" ALL TESTS COMPLETED!") print("=" * 60) except Exception as e: print(f"\nERROR: {e}") return False finally: await client.__aexit__(None, None, None) return True if __name__ == "__main__": success = asyncio.run(main()) sys.exit(0 if success else 1)
執行本機測試
-
在一個終端機中執行伺服器時,開啟新的終端機並執行測試用戶端:
python test_client.py -
用戶端會測試資源和提示,然後執行在完整工作流程中示範引出、進度通知和取樣
plan_trip的工具。
部署至 Amazon Bedrock AgentCore
設定和部署
-
如果您尚未安裝 AgentCore CLI:
npm install -g @aws/agentcore -
建立要部署的專案:
agentcore create --name TravelAgentDemo --protocol MCP -
部署代理程式:
agentcore deploy部署完成後,請注意輸出中提供的代理程式 ARN。
測試您部署的代理程式
測試部署的代理程式
-
設定必要的環境變數:
export AGENT_ARN='arn:aws:bedrock-agentcore:us-west-2:YOUR_ACCOUNT:runtime/YOUR_AGENT_NAME' export BEARER_TOKEN='your_bearer_token'將預留位置取代為您實際的客服人員 ARN 和承載字符。
-
在遠端模式下執行測試用戶端:
LOCAL_TEST=false python test_client.py -
用戶端將測試資源、提示和
plan_trip工具。遵循互動式提示來完成預訂,該預訂示範了已部署代理程式的引出、進度通知和取樣。
Agent ARN: arn:aws:bedrock-agentcore:us-west-2:123456789012:runtime/TravelAgentDemo Endpoint: https://bedrock-agentcore.us-west-2.amazonaws.com ============================================================ Travel Agent - MCP Feature Test Client ============================================================ Using auth token (len=1034) [1] Testing RESOURCES... Found 1 resource(s) [2] Testing PROMPTS... Found 2 prompt(s) [3] Testing PLAN_TRIP tool... (This tests Elicitation, Progress, and Sampling) >>> Server asks: Where would you like to go? Options: Paris, Tokyo, New York, Bali Your answer: Paris <<< Responding: Paris >>> Server asks: What type of trip? 1. business 2. leisure 3. family Your answer: leisure <<< Responding: leisure >>> Server asks: How many days? (3-14) Your answer (number): 5 <<< Responding: 5 >>> Server asks: Number of travelers? Your answer (number): 2 <<< Responding: 2 Progress: [####################] 100% (5/5) Done! >>> AI Sampling Request Prompt: Give 3 brief tips for a leisure trip to Paris, France for 2 travelers... Enter AI response (or Enter for auto): <<< AI Response: 1. Book popular attractions early. 2. Try local street food. 3. Learn basic greetings! >>> Server asks: ========== TRIP SUMMARY ========== Destination: Paris, France Trip Type: leisure Duration: 5 days Travelers: 2 COSTS: Flights: $900 Hotels: $900 (1 room(s) x 5 nights) TOTAL: $1800 Confirm booking? (Yes/No) 1. Yes 2. No Your choice (number): 1 <<< Responding: Yes ============================================================ RESULT: ============================================================ ================================================== BOOKING CONFIRMED! ================================================== Booking Reference: TRV-A1B2C3D4 TRIP DETAILS: Paris, France 5 days | 2 traveler(s) Trip type: leisure FLIGHTS: $900 Outbound: Day 1, Morning departure Return: Day 5, Evening departure ACCOMMODATION: $900 1 room(s) for 5 nights TOTAL PAID: $1800 HIGHLIGHTS TO EXPLORE: * Eiffel Tower * Louvre * Notre-Dame USEFUL PHRASES: * Bonjour * Merci * S'il vous plait AI RECOMMENDATIONS: 1. Book popular attractions early. 2. Try local street food. 3. Learn basic greetings! ================================================== Thank you for booking with Travel Agent! ============================================================ ALL TESTS COMPLETED! ============================================================
提示
您也可以使用 MCP Inspector 來測試 MCP 伺服器,這是一種用於測試 MCP 伺服器的視覺化工具。如需本機測試說明,請參閱使用 MCP 檢查器進行本機測試。如需遠端測試說明,請參閱使用 MCP 檢查器進行遠端測試。