Ruleset at ${absolute} must be an object at the top level.

Error message

Ruleset at ${absolute} must be an object at the top level.

What it means

Error "Ruleset at ${absolute} must be an object at the top level." thrown in Kong/insomnia.

Source

Thrown at packages/insomnia/src/main/bundle-spectral-ruleset.ts:48

  }
  if (visited.has(absolute)) {
    throw new Error(`"extends" cycle detected at ${absolute}`);
  }
  if (!ALLOWED_EXTENSIONS.includes(path.extname(absolute).toLowerCase())) {
    throw new Error(`"extends" target must be a .yaml or .yml file: ${absolute}`);
  }
  const rel = path.relative(rootDir, absolute);
  if (rel.startsWith('..') || path.isAbsolute(rel)) {
    throw new Error(`"extends" target must stay within the ruleset's root directory: ${absolute}`);
  }
}

// Reads a local ruleset file from disk and parses it.
async function readRuleset(absolute: string): Promise<Ruleset> {
  const raw = await fs.promises.readFile(absolute, { encoding: 'utf8' });
  const parsed = YAML.parse(raw);
  if (parsed === null || typeof parsed !== 'object' || Array.isArray(parsed)) {
    throw new Error(`Ruleset at ${absolute} must be an object at the top level.`);
  }
  return parsed as Ruleset;
}

function isPlainObject(value: unknown): value is Record<string, unknown> {
  return value !== null && typeof value === 'object' && !Array.isArray(value);
}

// Shallow-merges top-level keys from source into target.
// Object values (e.g. "rules") are merged one level deep with source taking precedence.
// Scalar values are overwritten by source.
function mergeInto(target: Ruleset, source: Ruleset): void {
  for (const key of Object.keys(source)) {
    const sourceVal = source[key];
    const targetVal = target[key];
    target[key] = isPlainObject(targetVal) && isPlainObject(sourceVal) ? { ...targetVal, ...sourceVal } : sourceVal;
  }
}

View on GitHub (pinned to d9bb2b0142)

When it happens

Trigger: Thrown at packages/insomnia/src/main/bundle-spectral-ruleset.ts:48 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of Kong/insomnia@d9bb2b0142 (2026-08-26). Data as JSON: /api/errors/15207b3b8f689105. Report an issue: GitHub.