[GMLP-6388] Add support for Gumloop AuthError exception (#9)

Author: dvlpjrs

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "gumloop-mcp"
-version = "0.1.10"
+version = "0.1.11"
 description = "guMCP (Gumloop Model Context Protocol) SDK"
 readme = "README.md"
 requires-python = ">=3.10"

src/mcp/server/lowlevel/server.py

@@ -88,7 +88,7 @@ async def main():
 from mcp.server.models import InitializationOptions
 from mcp.server.session import ServerSession
 from mcp.shared.context import RequestContext
-from mcp.shared.exceptions import McpError
+from mcp.shared.exceptions import McpError, AuthError
 from mcp.shared.message import ServerMessageMetadata, SessionMessage
 from mcp.shared.session import RequestResponder
 
@@ -651,6 +651,18 @@ async def handler(req: types.CallToolRequest):
                             isError=False,
                         )
                     )
+                except AuthError as e:
+                    return types.ServerResult(
+                        types.CallToolResult(
+                            content=[
+                                types.TextContent(
+                                    type="text",
+                                    text=json.dumps(e.details.model_dump()),
+                                )
+                            ],
+                            isError=True,
+                        )
+                    )
                 except Exception as e:
                     return self._make_error_result(str(e))
 

src/mcp/shared/exceptions.py

@@ -1,4 +1,4 @@
-from mcp.types import ErrorData
+from mcp.types import ErrorData, AuthErrorData
 
 
 class McpError(Exception):
@@ -12,3 +12,16 @@ def __init__(self, error: ErrorData):
         """Initialize McpError."""
         super().__init__(error.message)
         self.error = error
+
+
+class AuthError(Exception):
+    """
+    Exception type raised for authentication and authorization failures.
+    """
+
+    details: AuthErrorData
+
+    def __init__(self, details: AuthErrorData):
+        """Initialize AuthError."""
+        super().__init__(details.message)
+        self.details = details

src/mcp/types.py

@@ -179,6 +179,24 @@ class ErrorData(BaseModel):
     model_config = ConfigDict(extra="allow")
 
 
+class AuthErrorData(BaseModel):
+    """Error information for authentication and authorization failures."""
+
+    error: str
+    """The error type identifier (e.g., 'credentials_not_found', 'invalid_token', 'insufficient_permissions')."""
+
+    message: str
+    """A human-readable error message."""
+
+    service: str
+    """The service name requiring authentication."""
+
+    error_status: int
+    """The HTTP status code (401, 403, 400, etc.)."""
+
+    model_config = ConfigDict(extra="allow")
+
+
 class JSONRPCError(BaseModel):
     """A response to a request that indicates an error occurred."""