docs: Update examples to use stateless HTTP with JSON responses (#1499)

examples/snippets/servers/fastmcp_quickstart.py

@@ -1,14 +1,14 @@
 """
 FastMCP quickstart example.
 
-cd to the `examples/snippets/clients` directory and run:
-    uv run server fastmcp_quickstart stdio
+Run from the repository root:
+    uv run examples/snippets/servers/fastmcp_quickstart.py
 """
 
 from mcp.server.fastmcp import FastMCP
 
 # Create an MCP server
-mcp = FastMCP("Demo")
+mcp = FastMCP("Demo", json_response=True)
 
 
 # Add an addition tool
@@ -36,3 +36,8 @@ def greet_user(name: str, style: str = "friendly") -> str:
     }
 
     return f"{styles.get(style, styles['friendly'])} for someone named {name}."
+
+
+# Run with streamable HTTP transport
+if __name__ == "__main__":
+    mcp.run(transport="streamable-http")

examples/snippets/servers/oauth_server.py

@@ -20,6 +20,7 @@ class SimpleTokenVerifier(TokenVerifier):
 # Create FastMCP instance as a Resource Server
 mcp = FastMCP(
     "Weather Service",
+    json_response=True,
     # Token verifier for authentication
     token_verifier=SimpleTokenVerifier(),
     # Auth settings for RFC 9728 Protected Resource Metadata

examples/snippets/servers/streamable_config.py

@@ -5,15 +5,15 @@ Run from the repository root:
 
 from mcp.server.fastmcp import FastMCP
 
-# Stateful server (maintains session state)
-mcp = FastMCP("StatefulServer")
+# Stateless server with JSON responses (recommended)
+mcp = FastMCP("StatelessServer", stateless_http=True, json_response=True)
 
 # Other configuration options:
-# Stateless server (no session persistence)
+# Stateless server with SSE streaming responses
 # mcp = FastMCP("StatelessServer", stateless_http=True)
 
-# Stateless server (no session persistence, no sse stream with supported client)
-# mcp = FastMCP("StatelessServer", stateless_http=True, json_response=True)
+# Stateful server with session persistence
+# mcp = FastMCP("StatefulServer")
 
 
 # Add a simple tool to demonstrate the server

examples/snippets/servers/streamable_http_basic_mounting.py

@@ -11,7 +11,7 @@ from starlette.routing import Mount
 from mcp.server.fastmcp import FastMCP
 
 # Create MCP server
-mcp = FastMCP("My App")
+mcp = FastMCP("My App", json_response=True)
 
 
 @mcp.tool()

examples/snippets/servers/streamable_http_host_mounting.py

@@ -11,7 +11,7 @@ from starlette.routing import Host
 from mcp.server.fastmcp import FastMCP
 
 # Create MCP server
-mcp = FastMCP("MCP Host App")
+mcp = FastMCP("MCP Host App", json_response=True)
 
 
 @mcp.tool()

examples/snippets/servers/streamable_http_multiple_servers.py

@@ -11,8 +11,8 @@ from starlette.routing import Mount
 from mcp.server.fastmcp import FastMCP
 
 # Create multiple MCP servers
-api_mcp = FastMCP("API Server")
-chat_mcp = FastMCP("Chat Server")
+api_mcp = FastMCP("API Server", json_response=True)
+chat_mcp = FastMCP("Chat Server", json_response=True)
 
 
 @api_mcp.tool()

examples/snippets/servers/streamable_http_path_config.py

@@ -12,7 +12,11 @@ from mcp.server.fastmcp import FastMCP
 
 # Configure streamable_http_path during initialization
 # This server will mount at the root of wherever it's mounted
-mcp_at_root = FastMCP("My Server", streamable_http_path="/")
+mcp_at_root = FastMCP(
+    "My Server",
+    json_response=True,
+    streamable_http_path="/",
+)
 
 
 @mcp_at_root.tool()

examples/snippets/servers/streamable_starlette_mount.py

@@ -11,7 +11,7 @@ from starlette.routing import Mount
 from mcp.server.fastmcp import FastMCP
 
 # Create the Echo server
-echo_mcp = FastMCP(name="EchoServer", stateless_http=True)
+echo_mcp = FastMCP(name="EchoServer", stateless_http=True, json_response=True)
 
 
 @echo_mcp.tool()
@@ -21,7 +21,7 @@ def echo(message: str) -> str:
 
 
 # Create the Math server
-math_mcp = FastMCP(name="MathServer", stateless_http=True)
+math_mcp = FastMCP(name="MathServer", stateless_http=True, json_response=True)
 
 
 @math_mcp.tool()