Update tests for prompts

README.md

@@ -173,10 +173,10 @@ Learn more in the [**Resources & Templates Documentation**](https://gofastmcp.co
 
 ### Prompts
 
-Prompts define reusable message templates to guide LLM interactions. Decorate functions with `@mcp.prompt()`. Return strings or `Message` objects.
+Prompts define reusable message templates to guide LLM interactions. Decorate functions with `@mcp.prompt`. Return strings or `Message` objects.
 
 ```python
-@mcp.prompt()
+@mcp.prompt
 def summarize_request(text: str) -> str:
     """Generate a prompt asking for a summary."""
     return f"Please summarize the following text:\n\n{text}"

docs/servers/context.mdx

@@ -71,7 +71,7 @@ async def get_user_profile(user_id: str, ctx: Context) -> dict:
 <VersionBadge version="2.2.5" />
 
 ```python
-@mcp.prompt()
+@mcp.prompt
 async def data_analysis_request(dataset: str, ctx: Context) -> str:
     """Generate a request to analyze data with contextual information."""
     # Context is available as the ctx parameter

docs/servers/fastmcp.mdx

@@ -87,7 +87,7 @@ See [Resources & Templates](/servers/resources) for detailed documentation.
 Prompts are reusable message templates for guiding the LLM.
 
 ```python
-@mcp.prompt()
+@mcp.prompt
 def analyze_data(data_points: list[float]) -> str:
     """Creates a prompt asking for analysis of numerical data."""
     formatted_data = ", ".join(str(point) for point in data_points)

docs/servers/prompts.mdx

@@ -33,13 +33,13 @@ from fastmcp.prompts.prompt import Message, PromptMessage, TextContent
 mcp = FastMCP(name="PromptServer")
 
 # Basic prompt returning a string (converted to user message automatically)
-@mcp.prompt()
+@mcp.prompt
 def ask_about_topic(topic: str) -> str:
     """Generates a user message asking for an explanation of a topic."""
     return f"Can you please explain the concept of '{topic}'?"
 
 # Prompt returning a specific message type
-@mcp.prompt()
+@mcp.prompt
 def generate_code_request(language: str, task_description: str) -> PromptMessage:
     """Generates a user message requesting code generation."""
     content = f"Write a {language} function that performs the following task: {task_description}"
@@ -69,7 +69,7 @@ FastMCP intelligently handles different return types from your prompt function:
 ```python
 from fastmcp.prompts.prompt import Message
 
-@mcp.prompt()
+@mcp.prompt
 def roleplay_scenario(character: str, situation: str) -> list[Message]:
     """Sets up a roleplaying scenario with initial messages."""
     return [
@@ -89,7 +89,7 @@ Type annotations are important for prompts. They:
 from pydantic import Field
 from typing import Literal, Optional
 
-@mcp.prompt()
+@mcp.prompt
 def generate_content_request(
     topic: str = Field(description="The main subject to cover"),
     format: Literal["blog", "email", "social"] = "blog",
@@ -111,7 +111,7 @@ def generate_content_request(
 Parameters in your function signature are considered **required** unless they have a default value.
 
 ```python
-@mcp.prompt()
+@mcp.prompt
 def data_analysis_prompt(
     data_uri: str,                        # Required - no default value
     analysis_type: str = "summary",       # Optional - has default value
@@ -154,13 +154,13 @@ FastMCP seamlessly supports both standard (`def`) and asynchronous (`async def`)
 
 ```python
 # Synchronous prompt
-@mcp.prompt()
+@mcp.prompt
 def simple_question(question: str) -> str:
     """Generates a simple question to ask the LLM."""
     return f"Question: {question}"
 
 # Asynchronous prompt
-@mcp.prompt()
+@mcp.prompt
 async def data_based_prompt(data_id: str) -> str:
     """Generates a prompt based on data that needs to be fetched."""
     # In a real scenario, you might fetch data from a database or API
@@ -183,7 +183,7 @@ from fastmcp import FastMCP, Context
 
 mcp = FastMCP(name="PromptServer")
 
-@mcp.prompt()
+@mcp.prompt
 async def generate_report_request(report_type: str, ctx: Context) -> str:
     """Generates a request for a report."""
     return f"Please create a {report_type} report. Request ID: {ctx.request_id}"
@@ -207,12 +207,12 @@ mcp = FastMCP(
     on_duplicate_prompts="error"  # Raise an error if a prompt name is duplicated
 )
 
-@mcp.prompt()
+@mcp.prompt
 def greeting(): return "Hello, how can I help you today?"
 
 # This registration attempt will raise a ValueError because
 # "greeting" is already registered and the behavior is "error".
-# @mcp.prompt()
+# @mcp.prompt
 # def greeting(): return "Hi there! What can I do for you?"
 ```
 

src/fastmcp/server/server.py

@@ -796,7 +796,7 @@ class FastMCP(Generic[LifespanResultT]):
 
         This decorator supports multiple calling patterns:
         - @server.prompt (without parentheses)
-        - @server.prompt() (with empty parentheses)
+        - @server.prompt (with empty parentheses)
         - @server.prompt("custom_name") (with name as first argument)
         - @server.prompt(name="custom_name") (with name as keyword argument)
         - server.prompt(function, name="custom_name") (direct function call)
@@ -818,7 +818,7 @@ class FastMCP(Generic[LifespanResultT]):
                     }
                 ]
 
-            @server.prompt()
+            @server.prompt
             def analyze_with_context(table_name: str, ctx: Context) -> list[Message]:
                 ctx.info(f"Analyzing table {table_name}")
                 schema = read_table_schema(table_name)

tests/client/test_client.py

@@ -53,7 +53,7 @@ def fastmcp_server():
         return {"id": user_id, "name": f"User {user_id}", "active": True}
 
     # Add a prompt
-    @server.prompt()
+    @server.prompt
     def welcome(name: str) -> str:
         """Example greeting prompt."""
         return f"Welcome to FastMCP, {name}!"

tests/client/test_sse.py

@@ -55,7 +55,7 @@ def fastmcp_server():
         return dict(request.headers)
 
     # Add a prompt
-    @server.prompt()
+    @server.prompt
     def welcome(name: str) -> str:
         """Example greeting prompt."""
         return f"Welcome to FastMCP, {name}!"

tests/client/test_streamable_http.py

@@ -55,7 +55,7 @@ def fastmcp_server():
         return dict(request.headers)
 
     # Add a prompt
-    @server.prompt()
+    @server.prompt
     def welcome(name: str) -> str:
         """Example greeting prompt."""
         return f"Welcome to FastMCP, {name}!"

tests/deprecated/test_deprecated.py

@@ -133,7 +133,7 @@ def test_mount_prompt_separator_deprecation_warning():
         main_app.mount("sub", sub_app, prompt_separator="-")
 
     # Verify the separator is ignored and the default is used
-    @sub_app.prompt()
+    @sub_app.prompt
     def test_prompt():
         return "test"
 

tests/deprecated/test_mount_separators.py

@@ -53,7 +53,7 @@ def test_mount_prompt_separator_deprecation_warning():
         main_app.mount("sub", sub_app, prompt_separator="-")
 
     # Verify the separator is ignored and the default is used
-    @sub_app.prompt()
+    @sub_app.prompt
     def test_prompt():
         return "test"
 

tests/server/http/test_http_dependencies.py

@@ -28,7 +28,7 @@ def fastmcp_server():
         return dict(request.headers)
 
     # Add a prompt
-    @server.prompt()
+    @server.prompt
     def get_headers_prompt() -> str:
         """Get the HTTP headers from the request."""
         request = get_http_request()

tests/server/test_import_server.py

@@ -130,7 +130,7 @@ async def test_import_with_prompts():
     assistant_app = FastMCP("AssistantApp")
 
     # Add a prompt to the assistant app
-    @assistant_app.prompt()
+    @assistant_app.prompt
     def greeting(name: str) -> str:
         return f"Hello, {name}!"
 
@@ -174,11 +174,11 @@ async def test_import_multiple_prompts():
     sql_app = FastMCP("SQLApp")
 
     # Add prompts to each app
-    @python_app.prompt()
+    @python_app.prompt
     def review_python(code: str) -> str:
         return f"Reviewing Python code:\n{code}"
 
-    @sql_app.prompt()
+    @sql_app.prompt
     def explain_sql(query: str) -> str:
         return f"Explaining SQL query:\n{query}"
 
@@ -316,7 +316,7 @@ async def test_import_with_proxy_prompts():
     main_app = FastMCP("MainApp")
     api_app = FastMCP("APIApp")
 
-    @api_app.prompt()
+    @api_app.prompt
     def greeting(name: str) -> str:
         """Example greeting prompt."""
         return f"Hello, {name} from API!"

tests/server/test_mount.py

@@ -194,7 +194,7 @@ class TestMultipleServerMount:
         def working_resource():
             return "Working resource"
 
-        @working_app.prompt()
+        @working_app.prompt
         def working_prompt() -> str:
             return "Working prompt"
 
@@ -384,7 +384,7 @@ class TestPrompts:
         main_app = FastMCP("MainApp")
         assistant_app = FastMCP("AssistantApp")
 
-        @assistant_app.prompt()
+        @assistant_app.prompt
         def greeting(name: str) -> str:
             return f"Hello, {name}!"
 
@@ -409,7 +409,7 @@ class TestPrompts:
         main_app.mount("assistant", assistant_app)
 
         # Add a prompt after mounting
-        @assistant_app.prompt()
+        @assistant_app.prompt
         def farewell(name: str) -> str:
             return f"Goodbye, {name}!"
 
@@ -507,7 +507,7 @@ class TestProxyServer:
         # Create original server
         original_server = FastMCP("OriginalServer")
 
-        @original_server.prompt()
+        @original_server.prompt
         def welcome(name: str) -> str:
             return f"Welcome, {name}!"
 

tests/server/test_proxy.py

@@ -61,7 +61,7 @@ def fastmcp_server():
 
     # --- Prompts ---
 
-    @server.prompt()
+    @server.prompt
     def welcome(name: str) -> str:
         return f"Welcome to FastMCP, {name}!"
 

tests/server/test_run_server.py

@@ -53,7 +53,7 @@
 
 #     # --- Prompts ---
 
-#     @server.prompt()
+#     @server.prompt
 #     def welcome(name: str) -> str:
 #         return f"Welcome to FastMCP, {name}!"
 

tests/server/test_server.py

@@ -659,7 +659,7 @@ class TestPromptDecorator:
     async def test_prompt_decorator(self):
         mcp = FastMCP()
 
-        @mcp.prompt()
+        @mcp.prompt
         def fn() -> str:
             return "Hello, world!"
 
@@ -720,7 +720,7 @@ class TestPromptDecorator:
     async def test_prompt_decorator_with_parameters(self):
         mcp = FastMCP()
 
-        @mcp.prompt()
+        @mcp.prompt
         def test_prompt(name: str, greeting: str = "Hello") -> str:
             return f"{greeting}, {name}!"
 
@@ -789,7 +789,7 @@ class TestPromptDecorator:
 
         class MyClass:
             @staticmethod
-            @mcp.prompt()
+            @mcp.prompt
             def test_prompt() -> str:
                 return "Static Hello, world!"
 
@@ -802,7 +802,7 @@ class TestPromptDecorator:
     async def test_prompt_decorator_async_function(self):
         mcp = FastMCP()
 
-        @mcp.prompt()
+        @mcp.prompt
         async def test_prompt() -> str:
             return "Async Hello, world!"
 

tests/server/test_server_interactions.py

@@ -1091,7 +1091,7 @@ class TestPrompts:
         """Test that the prompt decorator registers prompts correctly."""
         mcp = FastMCP()
 
-        @mcp.prompt()
+        @mcp.prompt
         def fn() -> str:
             return "Hello, world!"
 
@@ -1133,20 +1133,23 @@ class TestPrompts:
         content = await prompt.render()
         assert content[0].content.text == "Hello, world!"  # type: ignore[attr-defined]
 
-    def test_prompt_decorator_error(self):
-        """Test error when decorator is used incorrectly."""
+    async def test_prompt_decorator_with_parens(self):
         mcp = FastMCP()
-        with pytest.raises(TypeError, match="decorator was used incorrectly"):
 
-            @mcp.prompt  # type: ignore
-            def fn() -> str:
-                return "Hello, world!"
+        @mcp.prompt()
+        def fn() -> str:
+            return "Hello, world!"
+
+        prompts_dict = await mcp.get_prompts()
+        assert len(prompts_dict) == 1
+        prompt = prompts_dict["fn"]
+        assert prompt.name == "fn"
 
     async def test_list_prompts(self):
         """Test listing prompts through MCP protocol."""
         mcp = FastMCP()
 
-        @mcp.prompt()
+        @mcp.prompt
         def fn(name: str, optional: str = "default") -> str:
             return f"Hello, {name}! {optional}"
 
@@ -1169,7 +1172,7 @@ class TestPrompts:
         """Test getting a prompt through MCP protocol."""
         mcp = FastMCP()
 
-        @mcp.prompt()
+        @mcp.prompt
         def fn(name: str) -> str:
             return f"Hello, {name}!"
 
@@ -1185,7 +1188,7 @@ class TestPrompts:
         """Test getting a prompt that returns resource content."""
         mcp = FastMCP()
 
-        @mcp.prompt()
+        @mcp.prompt
         def fn() -> PromptMessage:
             return PromptMessage(
                 role="user",
@@ -1220,7 +1223,7 @@ class TestPrompts:
         """Test error when required arguments are missing."""
         mcp = FastMCP()
 
-        @mcp.prompt()
+        @mcp.prompt
         def prompt_fn(name: str) -> str:
             return f"Hello, {name}!"
 
@@ -1271,7 +1274,7 @@ class TestPromptContext:
     async def test_prompt_context(self):
         mcp = FastMCP()
 
-        @mcp.prompt()
+        @mcp.prompt
         def prompt_fn(name: str, ctx: Context) -> str:
             assert isinstance(ctx, Context)
             return f"Hello, {name}! {ctx.request_id}"

tests/test_servers/fastmcp_server.py

@@ -53,6 +53,6 @@ async def get_user(user_id: str) -> dict[str, Any] | None:
 # --- Prompts ---
 
 
-@server.prompt()
+@server.prompt
 def welcome(name: str) -> str:
     return f"Welcome to FastMCP, {name}!"