withastro/astro · error · Error

Unknown error parsing tsconfig.json or jsconfig.json. Could

Error message

Unknown error parsing tsconfig.json or jsconfig.json. Could not update TypeScript settings.

What it means

`astro add` runs updateTSConfig() to patch tsconfig/jsconfig for the newly added integration. If that routine returns 'failure' (the existing tsconfig.json or jsconfig.json could not be parsed as JSON, or could not be updated), `astro add` aborts by throwing this generic Error. The message is intentionally vague because the underlying parser already logged specifics.

Source

Thrown at packages/astro/src/cli/add/index.ts:465

	}

	const updateTSConfigResult = await updateTSConfig(cwd, logger, integrations, flags, {
		addIncludes: hasCloudflareIntegration ? ['./worker-configuration.d.ts'] : [],
	});

	switch (updateTSConfigResult) {
		case 'none': {
			break;
		}
		case 'cancelled': {
			logger.info(
				'SKIP_FORMAT',
				msg.cancelled(`Your TypeScript configuration has ${bold('NOT')} been updated.`),
			);
			break;
		}
		case 'failure': {
			throw new Error(
				`Unknown error parsing tsconfig.json or jsconfig.json. Could not update TypeScript settings.`,
			);
		}
		case 'updated':
			logger.info('SKIP_FORMAT', msg.success(`Successfully updated tsconfig`));
	}
}

function isAdapter(
	integration: IntegrationInfo,
): integration is IntegrationInfo & { type: 'adapter' } {
	return integration.type === 'adapter';
}

// Convert an arbitrary NPM package name into a JS identifier
// Some examples:
//  - @astrojs/image => image
//  - @astrojs/markdown-component => markdownComponent

View on GitHub (pinned to d081033d5f)

Solutions

Open tsconfig.json/jsconfig.json and run it through a JSON validator (or `npx tsc --noEmit` which will surface parse errors).
Remove trailing commas, quote all keys, and ensure comments are valid JSONC if your toolchain supports them.
Re-run `astro add <integration>` once the JSON parses cleanly.
If unsure, snapshot the file, replace with a minimal valid tsconfig, and re-apply your customizations after `astro add` finishes.
Check for a stray BOM: `file tsconfig.json` should say ASCII/UTF-8, not `UTF-8 Unicode (with BOM)`.

Example fix

// before — tsconfig.json
{
  "compilerOptions": {
    "strict": true,   // trailing comma + comment
  }
}

// after
{
  "compilerOptions": {
    "strict": true
  }
}

Defensive patterns

Strategy: validation

Validate before calling

import { readFileSync } from 'node:fs';
function tsconfigIsValidJson(path: string): boolean {
  const txt = readFileSync(path, 'utf8').replace(/\/\/.*$/gm, '').replace(/\/\*[\s\S]*?\*\//g, '');
  try { JSON.parse(txt); return true; } catch { return false; }
}

Type guard

function isParsableConfig(raw: string): boolean {
  try { JSON.parse(raw.replace(/\/\/.*$/gm,'').replace(/\/\*[\s\S]*?\*\//g,'').replace(/,\s*([}\]])/g,'$1')); return true; }
  catch { return false; }
}

Prevention

Run `tsc --noEmit` before `astro add` to surface config errors.
Avoid hand-editing tsconfig with trailing commas or single quotes.
Use a JSON-aware editor and keep comments consistent with JSONC support.

When it happens

Trigger: Running `astro add <integration>` when the project's tsconfig.json or jsconfig.json contains JSON syntax errors (trailing commas, unquoted keys, comments in a non-JSONC parse path, BOM/encoding issues), so updateTSConfig cannot read or rewrite it.

Common situations: Hand-edited tsconfig with a trailing comma or single-quoted string; tsconfig with `//` comments when the parser is not in JSONC mode; a corrupted/half-written tsconfig from a botched merge; a jsconfig with the same problems; an editor that auto-inserted a bad comma.

Related errors

AI-assisted analysis of withastro/astro@d081033d5f (2026-08-12). Data as JSON: /api/errors/77c4a2cdf142bae7. Report an issue: GitHub.