n8n-io/n8n · warning · Error

Content too large: ${byteSize} bytes (max ${MAX_FILE_SIZE} b

Error message

Content too large: ${byteSize} bytes (max ${MAX_FILE_SIZE} bytes).

What it means

Thrown by write_file when the content's UTF-8 byte length exceeds MAX_FILE_SIZE (1 MB). The check uses Buffer.byteLength(content, 'utf-8'), which counts bytes not characters — so multi-byte UTF-8 characters (emoji, CJK, etc.) each count as 2-4 bytes. The guard runs before any filesystem write occurs.

Source

Thrown at packages/@n8n/computer-use/src/tools/filesystem/write-file.ts:31

});

export const writeFileTool: ToolDefinition<typeof inputSchema> = {
	name: 'write_file',
	description:
		'Create a new file with the given content. Overwrites if the file already exists. Content must not exceed 1 MB.',
	inputSchema,
	annotations: {},
	async getAffectedResources({ filePath }, { dir }) {
		return [
			await buildFilesystemResource(dir, filePath, 'filesystemWrite', `Write file: ${filePath}`),
		];
	},
	async execute({ filePath, content }, { dir }) {
		const resolvedPath = await resolveSafePath(dir, filePath);

		const byteSize = Buffer.byteLength(content, 'utf-8');
		if (byteSize > MAX_FILE_SIZE) {
			throw new Error(`Content too large: ${byteSize} bytes (max ${MAX_FILE_SIZE} bytes).`);
		}

		await fs.mkdir(path.dirname(resolvedPath), { recursive: true });
		await fs.writeFile(resolvedPath, content, 'utf-8');

		return formatCallToolResult({ path: filePath });
	},
};

View on GitHub (pinned to 5ac6606e81)

Solutions

1. Split the content into multiple smaller files, each under 1 MB
2. Reduce the content size by removing unnecessary data or using a more compact format
3. Use shell tools to write large files via heredoc or output redirection

Example fix

// before (content exceeds 1 MB):
await write_file({ filePath: 'data.json', content: hugeJsonString });

// after (split into chunks):
for (let i = 0; i < chunks.length; i++) {
  await write_file({ filePath: `data-${i}.json`, content: chunks[i] });
}

import { MAX_FILE_SIZE } from './constants';

function isContentWithinLimit(content: string): boolean {
  return Buffer.byteLength(content, 'utf-8') <= MAX_FILE_SIZE;
}

// Before calling write_file:
if (!isContentWithinLimit(content)) {
  throw new Error(`Content is ${Buffer.byteLength(content, 'utf-8')} bytes, max is ${MAX_FILE_SIZE}. Split into multiple files.`);
}

function isContentTooLargeError(e: unknown): boolean {
  return e instanceof Error && e.message.startsWith('Content too large:');
}

When it happens

Trigger: Writing a large file — a big data export, a large generated source file, a base64-encoded binary payload, or a file with extensive multi-byte character content.

Common situations: Agent generates a large file content string from data aggregation, tries to write a large base64 payload, or creates a large data structure.

Related errors

• File too large: ${stat.size} bytes (max ${MAX_FILE_SIZE} byt
• oldString not found in file: ${filePath}
• Access denied: "${excludedSegment}" is excluded from filesys
• File too large: ${stat.size} bytes (max ${MAX_FILE_SIZE} byt
• Unsupported binary file — only PNG, JPEG, GIF, WebP and PDF

AI-assisted analysis of n8n-io/n8n@5ac6606e81 (2026-08-12). Data as JSON: /api/errors/1905553912e02e44. Report an issue: GitHub.