Set explicit destructiveHint=False, idempotentHint=True on READONLY annotation

Author: bigcat88

src/nextcloud_mcp/annotations.py

@@ -2,7 +2,7 @@
 
 from mcp.types import ToolAnnotations
 
-READONLY = ToolAnnotations(readOnlyHint=True)
+READONLY = ToolAnnotations(readOnlyHint=True, destructiveHint=False, idempotentHint=True)
 ADDITIVE = ToolAnnotations(readOnlyHint=False, destructiveHint=False, idempotentHint=False)
 ADDITIVE_IDEMPOTENT = ToolAnnotations(readOnlyHint=False, destructiveHint=False, idempotentHint=True)
 DESTRUCTIVE = ToolAnnotations(readOnlyHint=False, destructiveHint=True, idempotentHint=True)