Merge branch 'main' into RFC9728_www-authentication

Author: yurikunash

.github/workflows/shared.yml

@@ -29,6 +29,7 @@ jobs:
   test:
     runs-on: ${{ matrix.os }}
     timeout-minutes: 10
+    continue-on-error: true
     strategy:
       matrix:
         python-version: ["3.10", "3.11", "3.12", "3.13"]
@@ -48,8 +49,14 @@ jobs:
 
       - name: Run pytest
         run: uv run --frozen --no-sync pytest
-    continue-on-error: true
 
+      # This must run last as it modifies the environment!
+      - name: Run pytest with lowest versions
+        run: |
+          uv sync --all-extras --upgrade
+          uv run --no-sync pytest
+        env:
+          UV_RESOLUTION: lowest-direct
   readme-snippets:
     runs-on: ubuntu-latest
     steps:

.pre-commit-config.yaml

@@ -27,7 +27,6 @@ repos:
       - id: pyright
         name: pyright
         entry: uv run pyright
-        args: [src]
         language: system
         types: [python]
         pass_filenames: false

CLAUDE.md

@@ -16,7 +16,7 @@ This document contains critical information about working with this codebase. Fo
    - Public APIs must have docstrings
    - Functions must be focused and small
    - Follow existing patterns exactly
-   - Line length: 88 chars maximum
+   - Line length: 120 chars maximum
 
 3. Testing Requirements
    - Framework: `uv run --frozen pytest`
@@ -116,3 +116,15 @@ This document contains critical information about working with this codebase. Fo
    - Follow existing patterns
    - Document public APIs
    - Test thoroughly
+
+## Exception Handling
+
+- **Always use `logger.exception()` instead of `logger.error()` when catching exceptions**
+  - Don't include the exception in the message: `logger.exception("Failed")` not `logger.exception(f"Failed: {e}")`
+- **Catch specific exceptions** where possible:
+  - File ops: `except (OSError, PermissionError):`
+  - JSON: `except json.JSONDecodeError:`
+  - Network: `except (ConnectionError, TimeoutError):`
+- **Only catch `Exception` for**:
+  - Top-level handlers that must not crash
+  - Cleanup blocks (log at debug level)

README.md

@@ -546,7 +546,7 @@ _Full example: [examples/snippets/servers/completion.py](https://github.com/mode
 <!-- /snippet-source -->
 ### Elicitation
 
-Request additional information from users during tool execution:
+Request additional information from users. This example shows an Elicitation during a Tool Call:
 
 <!-- snippet-source examples/snippets/servers/elicitation.py -->
 ```python
@@ -1327,13 +1327,13 @@ The MCP protocol defines three core primitives that servers can implement:
 
 MCP servers declare capabilities during initialization:
 
-| Capability  | Feature Flag                 | Description                        |
-|-------------|------------------------------|------------------------------------|
-| `prompts`   | `listChanged`                | Prompt template management         |
-| `resources` | `subscribe`<br/>`listChanged`| Resource exposure and updates      |
-| `tools`     | `listChanged`                | Tool discovery and execution       |
-| `logging`   | -                            | Server logging configuration       |
-| `completion`| -                            | Argument completion suggestions    |
+| Capability   | Feature Flag                 | Description                        |
+|--------------|------------------------------|------------------------------------|
+| `prompts`    | `listChanged`                | Prompt template management         |
+| `resources`  | `subscribe`<br/>`listChanged`| Resource exposure and updates      |
+| `tools`      | `listChanged`                | Tool discovery and execution       |
+| `logging`    | -                            | Server logging configuration       |
+| `completions`| -                            | Argument completion suggestions    |
 
 ## Documentation
 

examples/servers/simple-auth/mcp_simple_auth/server.py

@@ -160,9 +160,8 @@ def main(port: int, auth_server: str, transport: Literal["sse", "streamable-http
         mcp_server.run(transport=transport)
         logger.info("Server stopped")
         return 0
-    except Exception as e:
-        logger.error(f"Server error: {e}")
-        logger.exception("Exception details:")
+    except Exception:
+        logger.exception("Server error")
         return 1
 
 

pyproject.toml

@@ -25,25 +25,25 @@ dependencies = [
     "anyio>=4.5",
     "httpx>=0.27",
     "httpx-sse>=0.4",
-    "pydantic>=2.7.2,<3.0.0",
+    "pydantic>=2.8.0,<3.0.0",
     "starlette>=0.27",
     "python-multipart>=0.0.9",
     "sse-starlette>=1.6.1",
     "pydantic-settings>=2.5.2",
     "uvicorn>=0.23.1; sys_platform != 'emscripten'",
     "jsonschema>=4.20.0",
+    "pywin32>=310; sys_platform == 'win32'",
 ]
 
 [project.optional-dependencies]
 rich = ["rich>=13.9.4"]
-cli = ["typer>=0.12.4", "python-dotenv>=1.0.0"]
+cli = ["typer>=0.16.0", "python-dotenv>=1.0.0"]
 ws = ["websockets>=15.0.1"]
 
 [project.scripts]
 mcp = "mcp.cli:app [cli]"
 
 [tool.uv]
-resolution = "lowest-direct"
 default-groups = ["dev", "docs"]
 required-version = ">=0.7.2"
 
@@ -58,6 +58,7 @@ dev = [
     "pytest-examples>=0.0.14",
     "pytest-pretty>=1.2.0",
     "inline-snapshot>=0.23.0",
+    "dirty-equals>=0.9.0",
 ]
 docs = [
     "mkdocs>=1.6.1",
@@ -124,5 +125,7 @@ filterwarnings = [
     # This should be fixed on Uvicorn's side.
     "ignore::DeprecationWarning:websockets",
     "ignore:websockets.server.WebSocketServerProtocol is deprecated:DeprecationWarning",
-    "ignore:Returning str or bytes.*:DeprecationWarning:mcp.server.lowlevel"
+    "ignore:Returning str or bytes.*:DeprecationWarning:mcp.server.lowlevel",
+    # pywin32 internal deprecation warning
+    "ignore:getargs.*The 'u' format is deprecated:DeprecationWarning"
 ]

src/mcp/cli/claude.py

@@ -75,11 +75,10 @@ def update_claude_config(
     if not config_file.exists():
         try:
             config_file.write_text("{}")
-        except Exception as e:
-            logger.error(
+        except Exception:
+            logger.exception(
                 "Failed to create Claude config file",
                 extra={
-                    "error": str(e),
                     "config_file": str(config_file),
                 },
             )
@@ -139,11 +138,10 @@ def update_claude_config(
             extra={"config_file": str(config_file)},
         )
         return True
-    except Exception as e:
-        logger.error(
+    except Exception:
+        logger.exception(
             "Failed to update Claude config",
             extra={
-                "error": str(e),
                 "config_file": str(config_file),
             },
         )

src/mcp/cli/cli.py

@@ -349,12 +349,11 @@ def run(
 
         server.run(**kwargs)
 
-    except Exception as e:
-        logger.error(
-            f"Failed to run server: {e}",
+    except Exception:
+        logger.exception(
+            "Failed to run server",
             extra={
                 "file": str(file),
-                "error": str(e),
             },
         )
         sys.exit(1)
@@ -464,8 +463,8 @@ def install(
             if dotenv:
                 try:
                     env_dict |= {k: v for k, v in dotenv.dotenv_values(env_file).items() if v is not None}
-                except Exception as e:
-                    logger.error(f"Failed to load .env file: {e}")
+                except (OSError, ValueError):
+                    logger.exception("Failed to load .env file")
                     sys.exit(1)
             else:
                 logger.error("python-dotenv is not installed. Cannot load .env file.")

src/mcp/client/auth.py

@@ -494,8 +494,8 @@ async def _handle_refresh_response(self, response: httpx.Response) -> bool:
             await self.context.storage.set_tokens(token_response)
 
             return True
-        except ValidationError as e:
-            logger.error(f"Invalid refresh response: {e}")
+        except ValidationError:
+            logger.exception("Invalid refresh response")
             self.context.clear_tokens()
             return False
 
@@ -570,7 +570,7 @@ async def async_auth_flow(self, request: httpx.Request) -> AsyncGenerator[httpx.
                         token_response = yield token_request
                         await self._handle_token_response(token_response)
                     except Exception as e:
-                        logger.error(f"OAuth flow error: {e}")
+                        logger.exception("OAuth flow error")
                         raise
 
                 # Retry with new tokens

src/mcp/client/sse.py

@@ -97,7 +97,7 @@ async def sse_reader(
                                             )
                                             logger.debug(f"Received server message: {message}")
                                         except Exception as exc:
-                                            logger.error(f"Error parsing server message: {exc}")
+                                            logger.exception("Error parsing server message")
                                             await read_stream_writer.send(exc)
                                             continue
 
@@ -106,7 +106,7 @@ async def sse_reader(
                                     case _:
                                         logger.warning(f"Unknown SSE event: {sse.event}")
                         except Exception as exc:
-                            logger.error(f"Error in sse_reader: {exc}")
+                            logger.exception("Error in sse_reader")
                             await read_stream_writer.send(exc)
                         finally:
                             await read_stream_writer.aclose()
@@ -126,8 +126,8 @@ async def post_writer(endpoint_url: str):
                                     )
                                     response.raise_for_status()
                                     logger.debug(f"Client message sent successfully: {response.status_code}")
-                        except Exception as exc:
-                            logger.error(f"Error in post_writer: {exc}")
+                        except Exception:
+                            logger.exception("Error in post_writer")
                         finally:
                             await write_stream.aclose()