alibaba/nacos · error · Error

${name} must be valid JSON

Error message

${name} must be valid JSON

What it means

Generic JSON validator in the new-agent console model. Wraps JSON.parse in a try/catch and throws this error (not a SyntaxError) when parsing fails. Used for fields like nativeDescriptor, agentCard, callInterfaces, and any object-typed field parsed via parseJson/parseAgentCardJson.

Source

Thrown at console-ui-next/src/pages/newAgent/agent-console-model.ts:115

  callInterfaces: string;
  basedOnVersion: string;
  author: string;
  changeDescription: string;
}

function required(value: string, name: string): string {
  const result = value.trim();
  if (!result) {
    throw new Error(`${name} is required`);
  }
  return result;
}

function parseJson(value: string, name: string): unknown {
  try {
    return JSON.parse(value);
  } catch {
    throw new Error(`${name} must be valid JSON`);
  }
}

function parseAgentCardJson(value: string): unknown {
  const withoutTrailingCommas = value.replace(
    /("(?:\\.|[^"\\])*")|,\s*([}\]])/g,
    (match, quoted, closing) => quoted || closing || match,
  );
  return parseJson(withoutTrailingCommas, 'agentCard');
}

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

function optionalString(value: unknown): string | undefined {
  return typeof value === 'string' && value.trim() ? value.trim() : undefined;
}

View on GitHub (pinned to 9b989acdf1)

Solutions

  1. Run the JSON through a linter (jsonlint) or use a JSON editor component with validation.
  2. Use double quotes for all keys and string values; remove trailing commas (except for agentCard where they are auto-stripped).
  3. Replace single quotes with double quotes; ensure strings are fully closed.

Example fix

// before
{name: 'my-agent',}

// after
{"name":"my-agent"}
Defensive patterns

Strategy: validation

Validate before calling

function safeJsonParse(text, name) {
  try { return JSON.parse(text); } catch { throw new Error(`${name} must be valid JSON`); }
}

Type guard

function isValidJson(text: string): boolean {
  try { JSON.parse(text); return true; } catch { return false; }
}

Try / catch

try { parseJson(value, 'nativeDescriptor'); } catch (e) {
  if (/must be valid JSON/.test(e.message)) { toast.error('Fix the JSON syntax'); }
}

Prevention

When it happens

Trigger: User enters a malformed JSON string in a JSON-typed field: trailing comma, unquoted keys, single quotes, or unterminated string. Note parseAgentCardJson strips trailing commas before calling parseJson, so trailing-comma agentCard input is tolerated.

Common situations: Hand-editing JSON in a textarea without schema assistance. Copy-paste from a JS object literal (unquoted keys, single quotes). Non-ASCII smart quotes breaking the parse.

Related errors

AI-assisted analysis of alibaba/nacos@9b989acdf1 (2026-08-14). Data as JSON: /api/errors/20dfb84224f38907. Report an issue: GitHub.