refactor: Update FastMCP examples to use new import path

Update all FastMCP examples to use mcp.server.fastmcp instead of fastmcp.
Add tests to verify example servers work correctly.

Changes:
- Update import paths in all example files
- Create test_examples.py to verify functionality
- Fix test assertions to match actual response format
This commit is contained in:
David Soria Parra
2024-12-18 14:31:08 +00:00
parent fe75f43ee6
commit 15cd7df87f
9 changed files with 613 additions and 0 deletions

View File

@@ -0,0 +1,28 @@
"""
FastMCP Complex inputs Example
Demonstrates validation via pydantic with complex models.
"""
from pydantic import BaseModel, Field
from typing import Annotated
from mcp.server.fastmcp import FastMCP
mcp = FastMCP("Shrimp Tank")
class ShrimpTank(BaseModel):
class Shrimp(BaseModel):
name: Annotated[str, Field(max_length=10)]
shrimp: list[Shrimp]
@mcp.tool()
def name_shrimp(
tank: ShrimpTank,
# You can use pydantic Field in function signatures for validation.
extra_names: Annotated[list[str], Field(max_length=10)],
) -> list[str]:
"""List all shrimp names in the tank"""
return [shrimp.name for shrimp in tank.shrimp] + extra_names

View File

@@ -0,0 +1,25 @@
"""
FastMCP Desktop Example
A simple example that exposes the desktop directory as a resource.
"""
from pathlib import Path
from mcp.server.fastmcp import FastMCP
# Create server
mcp = FastMCP("Demo")
@mcp.resource("dir://desktop")
def desktop() -> list[str]:
"""List the files in the user's desktop"""
desktop = Path.home() / "Desktop"
return [str(f) for f in desktop.iterdir()]
@mcp.tool()
def add(a: int, b: int) -> int:
"""Add two numbers"""
return a + b

30
examples/fastmcp/echo.py Normal file
View File

@@ -0,0 +1,30 @@
"""
FastMCP Echo Server
"""
from mcp.server.fastmcp import FastMCP
# Create server
mcp = FastMCP("Echo Server")
@mcp.tool()
def echo_tool(text: str) -> str:
"""Echo the input text"""
return text
@mcp.resource("echo://static")
def echo_resource() -> str:
return "Echo!"
@mcp.resource("echo://{text}")
def echo_template(text: str) -> str:
"""Echo the input text"""
return f"Echo: {text}"
@mcp.prompt("echo")
def echo_prompt(text: str) -> str:
return text

346
examples/fastmcp/memory.py Normal file
View File

@@ -0,0 +1,346 @@
# /// script
# dependencies = ["pydantic-ai-slim[openai]", "asyncpg", "numpy", "pgvector", "fastmcp"]
# ///
# uv pip install 'pydantic-ai-slim[openai]' asyncpg numpy pgvector fastmcp
"""
Recursive memory system inspired by the human brain's clustering of memories.
Uses OpenAI's 'text-embedding-3-small' model and pgvector for efficient similarity search.
"""
import asyncio
import math
import os
from dataclasses import dataclass
from datetime import datetime, timezone
from pathlib import Path
from typing import Annotated, Self
import asyncpg
import numpy as np
from openai import AsyncOpenAI
from pgvector.asyncpg import register_vector # Import register_vector
from pydantic import BaseModel, Field
from pydantic_ai import Agent
from mcp.server.fastmcp import FastMCP
MAX_DEPTH = 5
SIMILARITY_THRESHOLD = 0.7
DECAY_FACTOR = 0.99
REINFORCEMENT_FACTOR = 1.1
DEFAULT_LLM_MODEL = "openai:gpt-4o"
DEFAULT_EMBEDDING_MODEL = "text-embedding-3-small"
mcp = FastMCP(
"memory",
dependencies=[
"pydantic-ai-slim[openai]",
"asyncpg",
"numpy",
"pgvector",
],
)
DB_DSN = "postgresql://postgres:postgres@localhost:54320/memory_db"
# reset memory with rm ~/.fastmcp/{USER}/memory/*
PROFILE_DIR = (
Path.home() / ".fastmcp" / os.environ.get("USER", "anon") / "memory"
).resolve()
PROFILE_DIR.mkdir(parents=True, exist_ok=True)
def cosine_similarity(a: list[float], b: list[float]) -> float:
a_array = np.array(a, dtype=np.float64)
b_array = np.array(b, dtype=np.float64)
return np.dot(a_array, b_array) / (
np.linalg.norm(a_array) * np.linalg.norm(b_array)
)
async def do_ai[T](
user_prompt: str,
system_prompt: str,
result_type: type[T] | Annotated,
deps=None,
) -> T:
agent = Agent(
DEFAULT_LLM_MODEL,
system_prompt=system_prompt,
result_type=result_type,
)
result = await agent.run(user_prompt, deps=deps)
return result.data
@dataclass
class Deps:
openai: AsyncOpenAI
pool: asyncpg.Pool
async def get_db_pool() -> asyncpg.Pool:
async def init(conn):
await conn.execute("CREATE EXTENSION IF NOT EXISTS vector;")
await register_vector(conn)
pool = await asyncpg.create_pool(DB_DSN, init=init)
return pool
class MemoryNode(BaseModel):
id: int | None = None
content: str
summary: str = ""
importance: float = 1.0
access_count: int = 0
timestamp: float = Field(
default_factory=lambda: datetime.now(timezone.utc).timestamp()
)
embedding: list[float]
@classmethod
async def from_content(cls, content: str, deps: Deps):
embedding = await get_embedding(content, deps)
return cls(content=content, embedding=embedding)
async def save(self, deps: Deps):
async with deps.pool.acquire() as conn:
if self.id is None:
result = await conn.fetchrow(
"""
INSERT INTO memories (content, summary, importance, access_count, timestamp, embedding)
VALUES ($1, $2, $3, $4, $5, $6)
RETURNING id
""",
self.content,
self.summary,
self.importance,
self.access_count,
self.timestamp,
self.embedding,
)
self.id = result["id"]
else:
await conn.execute(
"""
UPDATE memories
SET content = $1, summary = $2, importance = $3,
access_count = $4, timestamp = $5, embedding = $6
WHERE id = $7
""",
self.content,
self.summary,
self.importance,
self.access_count,
self.timestamp,
self.embedding,
self.id,
)
async def merge_with(self, other: Self, deps: Deps):
self.content = await do_ai(
f"{self.content}\n\n{other.content}",
"Combine the following two texts into a single, coherent text.",
str,
deps,
)
self.importance += other.importance
self.access_count += other.access_count
self.embedding = [(a + b) / 2 for a, b in zip(self.embedding, other.embedding)]
self.summary = await do_ai(
self.content, "Summarize the following text concisely.", str, deps
)
await self.save(deps)
# Delete the merged node from the database
if other.id is not None:
await delete_memory(other.id, deps)
def get_effective_importance(self):
return self.importance * (1 + math.log(self.access_count + 1))
async def get_embedding(text: str, deps: Deps) -> list[float]:
embedding_response = await deps.openai.embeddings.create(
input=text,
model=DEFAULT_EMBEDDING_MODEL,
)
return embedding_response.data[0].embedding
async def delete_memory(memory_id: int, deps: Deps):
async with deps.pool.acquire() as conn:
await conn.execute("DELETE FROM memories WHERE id = $1", memory_id)
async def add_memory(content: str, deps: Deps):
new_memory = await MemoryNode.from_content(content, deps)
await new_memory.save(deps)
similar_memories = await find_similar_memories(new_memory.embedding, deps)
for memory in similar_memories:
if memory.id != new_memory.id:
await new_memory.merge_with(memory, deps)
await update_importance(new_memory.embedding, deps)
await prune_memories(deps)
return f"Remembered: {content}"
async def find_similar_memories(embedding: list[float], deps: Deps) -> list[MemoryNode]:
async with deps.pool.acquire() as conn:
rows = await conn.fetch(
"""
SELECT id, content, summary, importance, access_count, timestamp, embedding
FROM memories
ORDER BY embedding <-> $1
LIMIT 5
""",
embedding,
)
memories = [
MemoryNode(
id=row["id"],
content=row["content"],
summary=row["summary"],
importance=row["importance"],
access_count=row["access_count"],
timestamp=row["timestamp"],
embedding=row["embedding"],
)
for row in rows
]
return memories
async def update_importance(user_embedding: list[float], deps: Deps):
async with deps.pool.acquire() as conn:
rows = await conn.fetch(
"SELECT id, importance, access_count, embedding FROM memories"
)
for row in rows:
memory_embedding = row["embedding"]
similarity = cosine_similarity(user_embedding, memory_embedding)
if similarity > SIMILARITY_THRESHOLD:
new_importance = row["importance"] * REINFORCEMENT_FACTOR
new_access_count = row["access_count"] + 1
else:
new_importance = row["importance"] * DECAY_FACTOR
new_access_count = row["access_count"]
await conn.execute(
"""
UPDATE memories
SET importance = $1, access_count = $2
WHERE id = $3
""",
new_importance,
new_access_count,
row["id"],
)
async def prune_memories(deps: Deps):
async with deps.pool.acquire() as conn:
rows = await conn.fetch(
"""
SELECT id, importance, access_count
FROM memories
ORDER BY importance DESC
OFFSET $1
""",
MAX_DEPTH,
)
for row in rows:
await conn.execute("DELETE FROM memories WHERE id = $1", row["id"])
async def display_memory_tree(deps: Deps) -> str:
async with deps.pool.acquire() as conn:
rows = await conn.fetch(
"""
SELECT content, summary, importance, access_count
FROM memories
ORDER BY importance DESC
LIMIT $1
""",
MAX_DEPTH,
)
result = ""
for row in rows:
effective_importance = row["importance"] * (
1 + math.log(row["access_count"] + 1)
)
summary = row["summary"] or row["content"]
result += f"- {summary} (Importance: {effective_importance:.2f})\n"
return result
@mcp.tool()
async def remember(
contents: list[str] = Field(
description="List of observations or memories to store"
),
):
deps = Deps(openai=AsyncOpenAI(), pool=await get_db_pool())
try:
return "\n".join(
await asyncio.gather(*[add_memory(content, deps) for content in contents])
)
finally:
await deps.pool.close()
@mcp.tool()
async def read_profile() -> str:
deps = Deps(openai=AsyncOpenAI(), pool=await get_db_pool())
profile = await display_memory_tree(deps)
await deps.pool.close()
return profile
async def initialize_database():
pool = await asyncpg.create_pool(
"postgresql://postgres:postgres@localhost:54320/postgres"
)
try:
async with pool.acquire() as conn:
await conn.execute("""
SELECT pg_terminate_backend(pg_stat_activity.pid)
FROM pg_stat_activity
WHERE pg_stat_activity.datname = 'memory_db'
AND pid <> pg_backend_pid();
""")
await conn.execute("DROP DATABASE IF EXISTS memory_db;")
await conn.execute("CREATE DATABASE memory_db;")
finally:
await pool.close()
pool = await asyncpg.create_pool(DB_DSN)
try:
async with pool.acquire() as conn:
await conn.execute("CREATE EXTENSION IF NOT EXISTS vector;")
await register_vector(conn)
await conn.execute("""
CREATE TABLE IF NOT EXISTS memories (
id SERIAL PRIMARY KEY,
content TEXT NOT NULL,
summary TEXT,
importance REAL NOT NULL,
access_count INT NOT NULL,
timestamp DOUBLE PRECISION NOT NULL,
embedding vector(1536) NOT NULL
);
CREATE INDEX IF NOT EXISTS idx_memories_embedding ON memories USING hnsw (embedding vector_l2_ops);
""")
finally:
await pool.close()
if __name__ == "__main__":
asyncio.run(initialize_database())

View File

@@ -0,0 +1,19 @@
from mcp.server.fastmcp import FastMCP
# Create an MCP server
mcp = FastMCP("Demo")
# Add an addition tool
@mcp.tool()
def add(a: int, b: int) -> int:
"""Add two numbers"""
return a + b
# Add a dynamic greeting resource
@mcp.resource("greeting://{name}")
def get_greeting(name: str) -> str:
"""Get a personalized greeting"""
return f"Hello, {name}!"

View File

@@ -0,0 +1,29 @@
"""
FastMCP Screenshot Example
Give Claude a tool to capture and view screenshots.
"""
import io
from mcp.server.fastmcp import FastMCP
from mcp.server.fastmcp.utilities.types import Image
# Create server
mcp = FastMCP("Screenshot Demo", dependencies=["pyautogui", "Pillow"])
@mcp.tool()
def take_screenshot() -> Image:
"""
Take a screenshot of the user's screen and return it as an image. Use
this tool anytime the user wants you to look at something they're doing.
"""
import pyautogui
buffer = io.BytesIO()
# if the file exceeds ~1MB, it will be rejected by Claude
screenshot = pyautogui.screenshot()
screenshot.convert("RGB").save(buffer, format="JPEG", quality=60, optimize=True)
return Image(data=buffer.getvalue(), format="jpeg")

View File

@@ -0,0 +1,15 @@
"""
FastMCP Echo Server
"""
from mcp.server.fastmcp import FastMCP
# Create server
mcp = FastMCP("Echo Server")
@mcp.tool()
def echo(text: str) -> str:
"""Echo the input text"""
return text

View File

@@ -0,0 +1,71 @@
# /// script
# dependencies = ["fastmcp"]
# ///
"""
FastMCP Text Me Server
--------------------------------
This defines a simple FastMCP server that sends a text message to a phone number via https://surgemsg.com/.
To run this example, create a `.env` file with the following values:
SURGE_API_KEY=...
SURGE_ACCOUNT_ID=...
SURGE_MY_PHONE_NUMBER=...
SURGE_MY_FIRST_NAME=...
SURGE_MY_LAST_NAME=...
Visit https://surgemsg.com/ and click "Get Started" to obtain these values.
"""
from typing import Annotated
import httpx
from pydantic import BeforeValidator
from pydantic_settings import BaseSettings, SettingsConfigDict
from mcp.server.fastmcp import FastMCP
class SurgeSettings(BaseSettings):
model_config: SettingsConfigDict = SettingsConfigDict(
env_prefix="SURGE_", env_file=".env"
)
api_key: str
account_id: str
my_phone_number: Annotated[
str, BeforeValidator(lambda v: "+" + v if not v.startswith("+") else v)
]
my_first_name: str
my_last_name: str
# Create server
mcp = FastMCP("Text me")
surge_settings = SurgeSettings() # type: ignore
@mcp.tool(name="textme", description="Send a text message to me")
def text_me(text_content: str) -> str:
"""Send a text message to a phone number via https://surgemsg.com/"""
with httpx.Client() as client:
response = client.post(
"https://api.surgemsg.com/messages",
headers={
"Authorization": f"Bearer {surge_settings.api_key}",
"Surge-Account": surge_settings.account_id,
"Content-Type": "application/json",
},
json={
"body": text_content,
"conversation": {
"contact": {
"first_name": surge_settings.my_first_name,
"last_name": surge_settings.my_last_name,
"phone_number": surge_settings.my_phone_number,
}
},
},
)
response.raise_for_status()
return f"Message sent: {text_content}"