Delete Block
delete_blockRemove a block from a Mnemosyne knowledge graph document by its ID, with an option to delete all related child blocks in a cascade operation.
Instructions
Delete a block by its ID. Use cascade=true to also delete all subsequent blocks with higher indent (indent-based children). Returns the list of deleted block IDs.
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| graph_id | Yes | ||
| document_id | Yes | ||
| block_id | Yes | ||
| cascade | No |
Implementation Reference
- The MCP tool handler for 'delete_block', including the @server.tool decorator that registers it. Handles authentication, input validation, document connection, transaction-based deletion via helper, and structured response.
@server.tool( name="delete_block", title="Delete Block", description=( "Delete a block by its ID. Use cascade=true to also delete all subsequent blocks " "with higher indent (indent-based children). Returns the list of deleted block IDs." ), ) async def delete_block_tool( graph_id: str, document_id: str, block_id: str, cascade: bool = False, context: Context | None = None, ) -> dict: """Delete a block and optionally its indent-children. Args: graph_id: The graph containing the document document_id: The document containing the block block_id: The block to delete cascade: If True, also delete indent-children """ auth = MCPAuthContext.from_context(context) auth.require_auth() if not graph_id or not graph_id.strip(): raise ValueError("graph_id is required") if not document_id or not document_id.strip(): raise ValueError("document_id is required") if not block_id or not block_id.strip(): raise ValueError("block_id is required") try: await hp_client.connect_document(graph_id.strip(), document_id.strip()) deleted_ids: list[str] = [] def perform_delete(doc: Any) -> None: nonlocal deleted_ids writer = DocumentWriter(doc) deleted_ids = writer.delete_block_by_id( block_id.strip(), cascade_children=cascade ) await hp_client.transact_document( graph_id.strip(), document_id.strip(), perform_delete, ) result = { "success": True, "graph_id": graph_id.strip(), "document_id": document_id.strip(), "deleted_block_ids": deleted_ids, "cascade": cascade, } return result except Exception as e: logger.error( "Failed to delete block", extra_context={ "graph_id": graph_id, "document_id": document_id, "block_id": block_id, "error": str(e), }, ) raise RuntimeError(f"Failed to delete block: {e}") - Core implementation of block deletion in DocumentWriter class, supporting optional cascade deletion of subsequent higher-indent child blocks. Called by the tool handler.
def delete_block_by_id(self, block_id: str, cascade_children: bool = False) -> list[str]: """Delete a block by its ID, optionally cascading to indent-children. Args: block_id: The block ID to delete cascade_children: If True, also delete all subsequent blocks with higher indent (indent-based children) Returns: List of deleted block IDs. Raises: ValueError: If block not found. """ result = self.find_block_by_id(block_id) if result is None: raise ValueError(f"Block not found: {block_id}") index, elem = result deleted_ids = [block_id] fragment = self.get_content_fragment() with self._doc.transaction(): if cascade_children: # Find children by indent parent_indent = _get_attr_safe(elem.attributes, "indent", 0) if isinstance(parent_indent, str): try: parent_indent = int(parent_indent) except ValueError: parent_indent = 0 children = list(fragment.children) # Collect indices to delete (in reverse order to maintain positions) indices_to_delete = [index] for i in range(index + 1, len(children)): child = children[i] if not hasattr(child, "attributes"): break child_indent = _get_attr_safe(child.attributes, "indent", 0) if isinstance(child_indent, str): try: child_indent = int(child_indent) except ValueError: child_indent = 0 if child_indent <= parent_indent: break # No longer a child indices_to_delete.append(i) child_id = _get_attr_safe(child.attributes, "data-block-id", None) if child_id: deleted_ids.append(child_id) # Delete in reverse order to maintain indices for idx in reversed(indices_to_delete): del fragment.children[idx] else: del fragment.children[index] return deleted_ids - src/neem/mcp/tools/hocuspocus.py:1153-1225 (registration)The @server.tool decorator registers the delete_block tool with the MCP server, defining its name, title, description (input/output schema), and handler function.
@server.tool( name="delete_block", title="Delete Block", description=( "Delete a block by its ID. Use cascade=true to also delete all subsequent blocks " "with higher indent (indent-based children). Returns the list of deleted block IDs." ), ) async def delete_block_tool( graph_id: str, document_id: str, block_id: str, cascade: bool = False, context: Context | None = None, ) -> dict: """Delete a block and optionally its indent-children. Args: graph_id: The graph containing the document document_id: The document containing the block block_id: The block to delete cascade: If True, also delete indent-children """ auth = MCPAuthContext.from_context(context) auth.require_auth() if not graph_id or not graph_id.strip(): raise ValueError("graph_id is required") if not document_id or not document_id.strip(): raise ValueError("document_id is required") if not block_id or not block_id.strip(): raise ValueError("block_id is required") try: await hp_client.connect_document(graph_id.strip(), document_id.strip()) deleted_ids: list[str] = [] def perform_delete(doc: Any) -> None: nonlocal deleted_ids writer = DocumentWriter(doc) deleted_ids = writer.delete_block_by_id( block_id.strip(), cascade_children=cascade ) await hp_client.transact_document( graph_id.strip(), document_id.strip(), perform_delete, ) result = { "success": True, "graph_id": graph_id.strip(), "document_id": document_id.strip(), "deleted_block_ids": deleted_ids, "cascade": cascade, } return result except Exception as e: logger.error( "Failed to delete block", extra_context={ "graph_id": graph_id, "document_id": document_id, "block_id": block_id, "error": str(e), }, ) raise RuntimeError(f"Failed to delete block: {e}") # -------------------------------------------------------------------------