Adding description field to the FastMCP get_prompt method

Issue: #602

Author: megandsouza03

src/mcp/server/fastmcp/server.py

@@ -531,9 +531,13 @@ async def get_prompt(
     ) -> GetPromptResult:
         """Get a prompt by name with arguments."""
         try:
+            prompt = self._prompt_manager.get_prompt(name)
             messages = await self._prompt_manager.render_prompt(name, arguments)
 
-            return GetPromptResult(messages=pydantic_core.to_jsonable_python(messages))
+            return GetPromptResult(
+                description=getattr(prompt, "description", None),
+                messages=pydantic_core.to_jsonable_python(messages),
+            )
         except Exception as e:
             logger.error(f"Error getting prompt {name}: {e}")
             raise ValueError(str(e))

tests/server/fastmcp/test_server.py

@@ -696,6 +696,19 @@ def fn(name: str) -> str:
             assert isinstance(content, TextContent)
             assert content.text == "Hello, World!"
 
+    @pytest.mark.anyio
+    async def test_get_prompt_with_description(self):
+        """Test getting a prompt through MCP protocol."""
+        mcp = FastMCP()
+
+        @mcp.prompt(description="Test prompt description")
+        def fn(name: str) -> str:
+            return f"Hello, {name}!"
+
+        async with client_session(mcp._mcp_server) as client:
+            result = await client.get_prompt("fn", {"name": "World"})
+            assert result.description == "Test prompt description"
+
     @pytest.mark.anyio
     async def test_get_prompt_with_resource(self):
         """Test getting a prompt that returns resource content."""