improve error messages for tools

Signed-off-by: phernandez <paul@basicmachines.co>

Author: phernandez

src/basic_memory/mcp/tools/delete_note.py

@@ -1,14 +1,157 @@
+from textwrap import dedent
 from typing import Optional
 
+from loguru import logger
+
 from basic_memory.mcp.tools.utils import call_delete
 from basic_memory.mcp.server import mcp
 from basic_memory.mcp.async_client import client
 from basic_memory.mcp.project_session import get_active_project
 from basic_memory.schemas import DeleteEntitiesResponse
 
 
+def _format_delete_error_response(error_message: str, identifier: str) -> str:
+    """Format helpful error responses for delete failures that guide users to successful deletions."""
+
+    # Note not found errors
+    if "entity not found" in error_message.lower() or "not found" in error_message.lower():
+        search_term = identifier.split("/")[-1] if "/" in identifier else identifier
+        title_format = (
+            identifier.split("/")[-1].replace("-", " ").title() if "/" in identifier else identifier
+        )
+        permalink_format = identifier.lower().replace(" ", "-")
+
+        return dedent(f"""
+            # Delete Failed - Note Not Found
+
+            The note '{identifier}' could not be found for deletion.
+
+            ## This might mean:
+            1. **Already deleted**: The note may have been deleted previously
+            2. **Wrong identifier**: The identifier format might be incorrect
+            3. **Different project**: The note might be in a different project
+
+            ## How to verify:
+            1. **Search for the note**: Use `search_notes("{search_term}")` to find it
+            2. **Try different formats**:
+               - If you used a permalink like "folder/note-title", try just the title: "{title_format}"
+               - If you used a title, try the permalink format: "{permalink_format}"
+
+            3. **Check if already deleted**: Use `list_directory("/")` to see what notes exist
+            4. **Check current project**: Use `get_current_project()` to verify you're in the right project
+
+            ## If the note actually exists:
+            ```
+            # First, find the correct identifier:
+            search_notes("{identifier}")
+
+            # Then delete using the correct identifier:
+            delete_note("correct-identifier-from-search")
+            ```
+
+            ## If you want to delete multiple similar notes:
+            Use search to find all related notes and delete them one by one.
+            """).strip()
+
+    # Permission/access errors
+    if (
+        "permission" in error_message.lower()
+        or "access" in error_message.lower()
+        or "forbidden" in error_message.lower()
+    ):
+        return f"""# Delete Failed - Permission Error
+
+You don't have permission to delete '{identifier}': {error_message}
+
+## How to resolve:
+1. **Check permissions**: Verify you have delete/write access to this project
+2. **File locks**: The note might be open in another application
+3. **Project access**: Ensure you're in the correct project with proper permissions
+
+## Alternative actions:
+- Check current project: `get_current_project()`
+- Switch to correct project: `switch_project("project-name")`
+- Verify note exists first: `read_note("{identifier}")`
+
+## If you have read-only access:
+Send a message to support@basicmachines.co to request deletion, or ask someone with write access to delete the note."""
+
+    # Server/filesystem errors
+    if (
+        "server error" in error_message.lower()
+        or "filesystem" in error_message.lower()
+        or "disk" in error_message.lower()
+    ):
+        return f"""# Delete Failed - System Error
+
+A system error occurred while deleting '{identifier}': {error_message}
+
+## Immediate steps:
+1. **Try again**: The error might be temporary
+2. **Check file status**: Verify the file isn't locked or in use
+3. **Check disk space**: Ensure the system has adequate storage
+
+## Troubleshooting:
+- Verify note exists: `read_note("{identifier}")`
+- Check project status: `get_current_project()`
+- Try again in a few moments
+
+## If problem persists:
+Send a message to support@basicmachines.co - there may be a filesystem or database issue."""
+
+    # Database/sync errors
+    if "database" in error_message.lower() or "sync" in error_message.lower():
+        return f"""# Delete Failed - Database Error
+
+A database error occurred while deleting '{identifier}': {error_message}
+
+## This usually means:
+1. **Sync conflict**: The file system and database are out of sync
+2. **Database lock**: Another operation is accessing the database
+3. **Corrupted entry**: The database entry might be corrupted
+
+## Steps to resolve:
+1. **Try again**: Wait a moment and retry the deletion
+2. **Check note status**: `read_note("{identifier}")` to see current state
+3. **Manual verification**: Use `list_directory()` to see if file still exists
+
+## If the note appears gone but database shows it exists:
+Send a message to support@basicmachines.co - a manual database cleanup may be needed."""
+
+    # Generic fallback
+    return f"""# Delete Failed
+
+Error deleting note '{identifier}': {error_message}
+
+## General troubleshooting:
+1. **Verify the note exists**: `read_note("{identifier}")` or `search_notes("{identifier}")`
+2. **Check permissions**: Ensure you can edit/delete files in this project
+3. **Try again**: The error might be temporary
+4. **Check project**: Make sure you're in the correct project
+
+## Step-by-step approach:
+```
+# 1. Confirm note exists and get correct identifier
+search_notes("{identifier}")
+
+# 2. Read the note to verify access
+read_note("correct-identifier-from-search")
+
+# 3. Try deletion with correct identifier
+delete_note("correct-identifier-from-search")
+```
+
+## Alternative approaches:
+- Check what notes exist: `list_directory("/")`
+- Verify current project: `get_current_project()`
+- Switch projects if needed: `switch_project("correct-project")`
+
+## Need help?
+If the note should be deleted but the operation keeps failing, send a message to support@basicmachines.co."""
+
+
 @mcp.tool(description="Delete a note by title or permalink")
-async def delete_note(identifier: str, project: Optional[str] = None) -> bool:
+async def delete_note(identifier: str, project: Optional[str] = None) -> bool | str:
     """Delete a note from the knowledge base.
 
     Args:
@@ -31,6 +174,18 @@ async def delete_note(identifier: str, project: Optional[str] = None) -> bool:
     active_project = get_active_project(project)
     project_url = active_project.project_url
 
-    response = await call_delete(client, f"{project_url}/knowledge/entities/{identifier}")
-    result = DeleteEntitiesResponse.model_validate(response.json())
-    return result.deleted
+    try:
+        response = await call_delete(client, f"{project_url}/knowledge/entities/{identifier}")
+        result = DeleteEntitiesResponse.model_validate(response.json())
+
+        if result.deleted:
+            logger.info(f"Successfully deleted note: {identifier}")
+            return True
+        else:
+            logger.warning(f"Delete operation completed but note was not deleted: {identifier}")
+            return False
+
+    except Exception as e:
+        logger.error(f"Delete failed for '{identifier}': {e}")
+        # Return formatted error message for better user experience
+        return _format_delete_error_response(str(e), identifier)