What causes "Failed to parse settings.json: ${e.message}" in jackwener/OpenCLI?

Open settings.json and fix or remove the invalid JSON (trailing commas, comments, unquoted keys)

jackwener/OpenCLI · error · CommandExecutionError

Failed to parse settings.json: ${e.message}

Error message

Failed to parse settings.json: ${e.message}

What it means

Error "Failed to parse settings.json: ${e.message}" thrown in jackwener/OpenCLI.

Source

Thrown at clis/antigravity/storage.js:358

    strategy: Strategy.LOCAL,
    browser: false,
    args: [],
    columns: STORAGE_COLUMNS,
    func: async () => {
        if (!fs.existsSync(AG_SETTINGS_JSON)) {
            throw new CommandExecutionError(`settings.json not found: ${AG_SETTINGS_JSON}`, '');
        }
        const raw = fs.readFileSync(AG_SETTINGS_JSON, 'utf-8');
        // VSCode allows JSONC (line + block comments + trailing commas).
        // Strip comments and trailing commas before parsing.
        const stripped = raw
            .replace(/\/\*[\s\S]*?\*\//g, '')              // block comments
            .replace(/^\s*\/\/.*$/gm, '')                  // line comments (full line)
            .replace(/([^:"])\/\/.*$/gm, '$1')             // line comments (after code)
            .replace(/,(\s*[}\]])/g, '$1');                // trailing commas
        let obj;
        try { obj = JSON.parse(stripped); } catch (e) {
            throw new CommandExecutionError(`Failed to parse settings.json: ${e.message}`, '');
        }
        const rows = [];
        for (const [k, v] of Object.entries(obj)) {
            rows.push({ Field: k, Value: typeof v === 'object' ? JSON.stringify(v) : String(v) });
        }
        return rows;
    },
});

View on GitHub (pinned to 49907e53dc)

Solutions

Open settings.json and fix or remove the invalid JSON (trailing commas, comments, unquoted keys)
Restore settings.json from a backup or delete it to regenerate defaults
Validate with a JSON linter before saving

Defensive patterns

Strategy: try-catch

Validate before calling

import * as fs from 'node:fs';
const raw = fs.readFileSync(settingsPath, 'utf-8');
const stripped = raw
  .replace(/\/\*[\s\S]*?\*\//g, '')
  .replace(/^\s*\/\/.*$/gm, '')
  .replace(/([^:"])\/\/.*$/gm, '$1')
  .replace(/,(\s*[}\]])/g, '$1');
try { JSON.parse(stripped); } catch (e) {
  console.error(`settings.json will not parse even after JSONC stripping: ${e.message}`);
}

Type guard

function isParsableJsonc(text) {
  try {
    const stripped = text.replace(/\/\*[\s\S]*?\*\//g, '')
      .replace(/^\s*\/\/.*$/gm, '')
      .replace(/([^:"])\/\/.*$/gm, '$1')
      .replace(/,(\s*[}\]])/g, '$1');
    JSON.parse(stripped);
    return true;
  } catch { return false; }
}

Try / catch

try {
  await cli.run(['antigravity', 'settings-read']);
} catch (e) {
  if (String(e.message).startsWith('Failed to parse settings.json')) {
    console.error(`Malformed settings.json: ${e.message}. Fix syntax at the reported position.`);
  } else throw e;
}

Prevention

Validate settings.json with a JSONC-aware linter after hand-editing
Beware the regex stripper can mangle URLs in values (// inside strings) — keep URL settings on lines where ([^:"])// won't match, or verify output
Keep a backup of settings.json before bulk edits

When it happens

Trigger: Thrown at clis/antigravity/storage.js:358 when the library encounters an invalid state.

Common situations: See trigger scenarios.

Understand the failure class

Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

AI-assisted analysis of jackwener/OpenCLI@49907e53dc (2026-08-29). Data as JSON: /api/errors/7894f888e8c6300e. Report an issue: GitHub.