Claude Code gets stuck in 'clauding...' loop with large JSON + non-ASCII URL prompt

Bug Description

Claude Code gets stuck in an infinite "clauding..." loop and never produces a response. The UI shows the loading indicator indefinitely with no output.

Steps to Reproduce

1. Open Claude Code (via Claude Desktop app)
2. Provide a prompt that combines:

• A large JSON file (~600 lines, an n8n workflow export) attached/referenced
• A URL containing non-ASCII characters (Hebrew UTF-8 encoded path segments)
• Multiple instructions in a single prompt (read, edit, and reference external URL)

1. Claude enters "clauding..." state and never responds
2. The only way to recover is to cancel (Ctrl+C / Escape) or restart

Example prompt structure:

<attached: large-workflow.json>
read my n8n workflow which currently only downloads the primary image. edit the json to download all the images of a product, to get all angles and send to gemini.
https://example.com/product/hebrew-characters-here/
tell it to not invent anything but use the actual look of the bag.

The JSON file is approximately 600 lines containing embedded JavaScript code blocks (n8n Code nodes with long multiline strings).

Expected Behavior

Claude should read the JSON, process the instructions, and respond — even if the task is complex.

Actual Behavior

Claude shows "clauding..." indefinitely with no response generated. No error message is shown.

Environment

• Claude Code version: 2.1.51 (bundled with Claude Desktop)
• Claude Desktop version: 1.1.4498
• Model: claude-opus-4-6
• OS: macOS 15.7.3 (Darwin 24.6.0)
• Platform: Apple Silicon (darwin)

Additional Context

• The issue is reproducible with the same prompt
• The JSON file contains large inline JavaScript strings (image prompt templates ~500+ chars each)
• The URL contains percent-encoded Hebrew characters
• A fresh conversation (/clear) and retry did not help
• Updating CLI to v2.1.70 was attempted as a potential fix

🤖 Generated with Claude Code