eyaltoledano/claude-task-master · error

CORE_FUNCTION_ERROR

CORE_FUNCTION_ERROR

Error message

${error.message}

What it means

This is the catch-all handler at the end of removeSubtaskDirect: any exception thrown by the wrapper or the core removeSubtask call (e.g. missing tasks.json file, JSON parse failure, subtask not found) is converted into a structured failure with code CORE_FUNCTION_ERROR and the underlying error's message. It means the failure happened inside the core task-manager logic, not in argument validation.

Source

Thrown at mcp-server/src/core/direct-functions/remove-subtask.js:123

			};
		} else {
			// Return simple success message for deletion
			return {
				success: true,
				data: {
					message: `Subtask ${id} successfully removed`
				}
			};
		}
	} catch (error) {
		// Ensure silent mode is disabled even if an outer error occurs
		disableSilentMode();

		log.error(`Error in removeSubtaskDirect: ${error.message}`);
		return {
			success: false,
			error: {
				code: 'CORE_FUNCTION_ERROR',
				message: error.message
			}
		};
	}
}

View on GitHub (pinned to c0c98d367c)

Solutions

1. Read the `message` in the error payload — it is the raw underlying error and usually names the file or id at fault.
2. Verify tasksJsonPath exists and is valid JSON (jq . tasks.json) before retrying.
3. Confirm the subtask id exists in tasks.json under the given parent (and the correct tag).
4. Check file/directory write permissions for the tasks.json location.
5. Enable debug logging in the MCP server to capture the full stack from task-manager.removeSubtask.

Example fix

// before
// opaque CORE_FUNCTION_ERROR: ENOENT: no such file or directory, open '.taskmaster/task.json'
const tasksJsonPath = '.taskmaster/task.json';
// after
const tasksJsonPath = '/repo/.taskmaster/tasks.json'; // corrected path
if (!fs.existsSync(tasksJsonPath)) throw new Error(`tasks.json not found: ${tasksJsonPath}`);

function precheck(tasksJsonPath, id) {
  const fs = require('fs');
  if (!fs.existsSync(tasksJsonPath)) throw new Error(`tasks.json not found: ${tasksJsonPath}`);
  const data = JSON.parse(fs.readFileSync(tasksJsonPath, 'utf8'));
  const [parentId, subId] = String(id).split('.').map(Number);
  const parent = (data.tasks || []).find((t) => t.id === parentId);
  if (!parent || !(parent.subtasks || []).some((s) => s.id === subId)) {
    throw new Error(`Subtask ${id} not found in ${tasksJsonPath}`);
  }
}

function isCoreFunctionError(result) {
  return typeof result === 'object' && result !== null && result.success === false &&
    result.error?.code === 'CORE_FUNCTION_ERROR' && typeof result.error.message === 'string';
}

const result = await removeSubtaskDirect(args, log);
if (!result.success && result.error?.code === 'CORE_FUNCTION_ERROR') {
  console.error(`removeSubtask failed: ${result.error.message}`);
  // inspect underlying cause: missing file, bad JSON, nonexistent subtask
}

When it happens

Trigger: tasksJsonPath points to a nonexistent or unreadable file; tasks.json is malformed JSON; the referenced subtask id does not exist under the parent; file-system permission errors during write-back; any throw inside scripts/modules/task-manager.js removeSubtask.

Common situations: Wrong tasksJsonPath (typo or stale path after moving the project); tasks.json corrupted or manually edited with invalid JSON; removing a subtask that was already removed; tag-scoped file missing.

Related errors

• CORE_FUNCTION_ERROR
• CORE_FUNCTION_ERROR
• CORE_FUNCTION_ERROR
• FIX_DEPENDENCIES_ERROR
• INITIALIZATION_FAILED

AI-assisted analysis of eyaltoledano/claude-task-master@c0c98d367c (2026-08-29). Data as JSON: /api/errors/c3b6d77af7d6df42. Report an issue: GitHub.