fix: Resolve lint issues and formatting

- Move ReadResourceContents import to top of file in lowlevel example
- Use union syntax (X | Y) instead of tuple in isinstance call
- Fix line length issue by breaking long function signature
- Add proper type annotations for consistency

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: alexanderreiff

examples/snippets/servers/lowlevel/resource_contents_direct.py

@@ -1,5 +1,5 @@
 """
-Example showing how to return ResourceContents objects directly from 
+Example showing how to return ResourceContents objects directly from
 low-level server resources.
 
 The main benefit is the ability to include metadata (_meta field) with
@@ -15,7 +15,7 @@
 import mcp.server.stdio as stdio
 import mcp.types as types
 from mcp.server import NotificationOptions, Server
-
+from mcp.server.lowlevel.server import ReadResourceContents
 
 # Create a server instance
 server = Server(
@@ -29,7 +29,7 @@
 async def read_resource(uri: AnyUrl) -> Iterable[types.TextResourceContents | types.BlobResourceContents]:
     """Handle resource reading with direct ResourceContents return."""
     uri_str = str(uri)
-    
+
     if uri_str == "text://readme":
         # Return TextResourceContents with document metadata
         return [
@@ -44,10 +44,10 @@ async def read_resource(uri: AnyUrl) -> Iterable[types.TextResourceContents | ty
                     "version": "2.1.0",
                     "language": "en",
                     "license": "MIT",
-                }
+                },
             )
         ]
-    
+
     elif uri_str == "data://config.json":
         # Return JSON data with schema and validation metadata
         return [
@@ -61,13 +61,14 @@ async def read_resource(uri: AnyUrl) -> Iterable[types.TextResourceContents | ty
                     "environment": "production",
                     "lastValidated": "2024-01-15T14:00:00Z",
                     "checksum": "sha256:abc123...",
-                }
+                },
             )
         ]
-    
+
     elif uri_str == "image://icon.png":
         # Return binary data with comprehensive image metadata
         import base64
+
         # This is a 1x1 transparent PNG
         png_data = base64.b64decode(
             "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNkYPhfDwAChwGA60e6kgAAAABJRU5ErkJggg=="
@@ -89,10 +90,10 @@ async def read_resource(uri: AnyUrl) -> Iterable[types.TextResourceContents | ty
                     "hasAlpha": True,
                     "generated": "2024-01-15T12:00:00Z",
                     "generator": "Example MCP Server",
-                }
+                },
             )
         ]
-    
+
     elif uri_str == "multi://content":
         # Return multiple ResourceContents objects with part metadata
         return [
@@ -105,7 +106,7 @@ async def read_resource(uri: AnyUrl) -> Iterable[types.TextResourceContents | ty
                     "title": "Introduction",
                     "order": 1,
                     "required": True,
-                }
+                },
             ),
             types.TextResourceContents(
                 uri=uri,
@@ -117,7 +118,7 @@ async def read_resource(uri: AnyUrl) -> Iterable[types.TextResourceContents | ty
                     "order": 2,
                     "wordCount": 8,
                     "headingLevel": 2,
-                }
+                },
             ),
             types.BlobResourceContents(
                 uri=uri,
@@ -129,19 +130,19 @@ async def read_resource(uri: AnyUrl) -> Iterable[types.TextResourceContents | ty
                     "order": 3,
                     "encoding": "base64",
                     "originalSize": 19,
-                }
+                },
             ),
         ]
-    
+
     elif uri_str.startswith("code://"):
         # Extract language from URI for syntax highlighting
         language = uri_str.split("://")[1].split("/")[0]
         code_samples = {
             "python": ('def hello():\n    print("Hello, World!")', "text/x-python"),
             "javascript": ('console.log("Hello, World!");', "text/javascript"),
-            "html": ('<h1>Hello, World!</h1>', "text/html"),
+            "html": ("<h1>Hello, World!</h1>", "text/html"),
         }
-        
+
         if language in code_samples:
             code, mime_type = code_samples[language]
             return [
@@ -155,10 +156,10 @@ async def read_resource(uri: AnyUrl) -> Iterable[types.TextResourceContents | ty
                         "lineNumbers": True,
                         "executable": language in ["python", "javascript"],
                         "documentation": f"https://docs.example.com/languages/{language}",
-                    }
+                    },
                 )
             ]
-    
+
     # Default case - resource not found
     return [
         types.TextResourceContents(
@@ -228,14 +229,13 @@ async def list_legacy_resources() -> list[types.Resource]:
 
 
 # Mix old and new styles to show compatibility
-from mcp.server.lowlevel.server import ReadResourceContents
-
-
 @server.read_resource()
-async def read_legacy_resource(uri: AnyUrl) -> Iterable[ReadResourceContents | types.TextResourceContents]:
+async def read_legacy_resource(
+    uri: AnyUrl,
+) -> Iterable[ReadResourceContents | types.TextResourceContents | types.BlobResourceContents]:
     """Handle legacy resources alongside new ResourceContents."""
     uri_str = str(uri)
-    
+
     if uri_str == "legacy://text":
         # Old style - return ReadResourceContents
         return [
@@ -244,7 +244,7 @@ async def read_legacy_resource(uri: AnyUrl) -> Iterable[ReadResourceContents | t
                 mime_type="text/plain",
             )
         ]
-    
+
     # Delegate to the new handler for other resources
     return await read_resource(uri)
 
@@ -264,4 +264,4 @@ async def main():
 
 if __name__ == "__main__":
     # Run with: python resource_contents_direct.py
-    asyncio.run(main())
+    asyncio.run(main())

examples/snippets/servers/resource_contents_direct.py

@@ -17,11 +17,13 @@
 This metadata helps clients better understand and work with the resource content.
 """
 
-from mcp.server.fastmcp import FastMCP
-from mcp.types import TextResourceContents, BlobResourceContents
-from pydantic import AnyUrl
 import base64
 
+from pydantic import AnyUrl
+
+from mcp.server.fastmcp import FastMCP
+from mcp.types import BlobResourceContents, TextResourceContents
+
 mcp = FastMCP(name="Direct ResourceContents Example")
 
 
@@ -40,7 +42,7 @@ def get_report() -> TextResourceContents:
             "version": "1.2.0",
             "tags": ["monthly", "finance", "q1-2024"],
             "confidentiality": "internal",
-        }
+        },
     )
 
 
@@ -50,7 +52,7 @@ def get_logo() -> BlobResourceContents:
     """Return a logo image with metadata about dimensions and format."""
     # In a real app, you might read this from a file
     image_bytes = b"\x89PNG\r\n\x1a\n..."  # PNG header
-    
+
     return BlobResourceContents(
         uri=AnyUrl("image://logo"),
         blob=base64.b64encode(image_bytes).decode(),
@@ -64,7 +66,7 @@ def get_logo() -> BlobResourceContents:
             "hasAlpha": True,
             "fileSize": 24576,
             "lastModified": "2024-01-10T08:00:00Z",
-        }
+        },
     )
 
 
@@ -73,13 +75,14 @@ def get_logo() -> BlobResourceContents:
 async def get_metrics(metric_type: str) -> TextResourceContents:
     """Return metrics data with metadata about collection time and source."""
     import datetime
-    
+
     # Simulate collecting metrics
     metrics = {"cpu": 45.2, "memory": 78.5, "disk": 62.1}
     timestamp = datetime.datetime.now(datetime.UTC).isoformat()
-    
+
     if metric_type == "json":
         import json
+
         return TextResourceContents(
             uri=AnyUrl(f"data://metrics/{metric_type}"),
             text=json.dumps(metrics, indent=2),
@@ -90,7 +93,7 @@ async def get_metrics(metric_type: str) -> TextResourceContents:
                 "interval": "5s",
                 "aggregation": "average",
                 "host": "prod-server-01",
-            }
+            },
         )
     elif metric_type == "csv":
         csv_text = "metric,value\n" + "\n".join(f"{k},{v}" for k, v in metrics.items())
@@ -102,7 +105,7 @@ async def get_metrics(metric_type: str) -> TextResourceContents:
                 "timestamp": timestamp,
                 "columns": ["metric", "value"],
                 "row_count": len(metrics),
-            }
+            },
         )
     else:
         text = "\n".join(f"{k.upper()}: {v}%" for k, v in metrics.items())
@@ -113,7 +116,7 @@ async def get_metrics(metric_type: str) -> TextResourceContents:
             _meta={
                 "timestamp": timestamp,
                 "format": "human-readable",
-            }
+            },
         )
 
 
@@ -122,7 +125,7 @@ async def get_metrics(metric_type: str) -> TextResourceContents:
 def get_config() -> TextResourceContents:
     """Return application config with version and environment metadata."""
     import json
-    
+
     config = {
         "version": "1.0.0",
         "features": {
@@ -133,9 +136,9 @@ def get_config() -> TextResourceContents:
         "limits": {
             "max_file_size": 10485760,  # 10MB
             "max_connections": 100,
-        }
+        },
     }
-    
+
     return TextResourceContents(
         uri=AnyUrl("config://app"),
         text=json.dumps(config, indent=2),
@@ -146,7 +149,7 @@ def get_config() -> TextResourceContents:
             "environment": "production",
             "schema": "https://example.com/schemas/config/v1.0",
             "editable": False,
-        }
+        },
     )
 
 
@@ -156,7 +159,7 @@ async def get_users() -> TextResourceContents:
     """Return query results with execution time and row count."""
     import json
     import time
-    
+
     # Simulate database query
     start_time = time.time()
     users = [
@@ -165,7 +168,7 @@ async def get_users() -> TextResourceContents:
         {"id": 3, "name": "Charlie", "role": "user"},
     ]
     execution_time = time.time() - start_time
-    
+
     return TextResourceContents(
         uri=AnyUrl("db://query/users"),
         text=json.dumps(users, indent=2),
@@ -177,10 +180,10 @@ async def get_users() -> TextResourceContents:
             "database": "main",
             "cached": False,
             "timestamp": "2024-01-15T16:00:00Z",
-        }
+        },
     )
 
 
 if __name__ == "__main__":
     # Run with: python resource_contents_direct.py
-    mcp.run()
+    mcp.run()

src/mcp/server/fastmcp/resources/types.py

@@ -14,7 +14,7 @@
 from pydantic import AnyUrl, Field, ValidationInfo, validate_call
 
 from mcp.server.fastmcp.resources.base import Resource
-from mcp.types import BlobResourceContents, Icon, ResourceContents, TextResourceContents
+from mcp.types import BlobResourceContents, Icon, TextResourceContents
 
 
 class TextResource(Resource):
@@ -63,7 +63,7 @@ async def read(self) -> str | bytes | TextResourceContents | BlobResourceContent
 
             if isinstance(result, Resource):
                 return await result.read()
-            elif isinstance(result, (TextResourceContents, BlobResourceContents)):
+            elif isinstance(result, TextResourceContents | BlobResourceContents):
                 return result
             elif isinstance(result, bytes):
                 return result

tests/server/fastmcp/resources/test_resource_contents_direct.py

@@ -187,4 +187,4 @@ async def get_item_contents(category: str, item: str) -> TextResourceContents:
     assert isinstance(content, TextResourceContents)
     assert content.text == "Content for python in books"
     assert content.mimeType == "text/plain"
-    assert str(content.uri) == "resource://books/python"
+    assert str(content.uri) == "resource://books/python"

tests/server/test_read_resource_direct.py

@@ -188,4 +188,4 @@ async def read_resource(uri: AnyUrl) -> Iterable[types.TextResourceContents | ty
     content3 = result.root.contents[2]
     assert isinstance(content3, types.TextResourceContents)
     assert content3.text == "Third text content"
-    assert content3.mimeType == "text/markdown"
+    assert content3.mimeType == "text/markdown"