Rail Fence (Zigzag) Cipher Encode/Decode

Choose this endpoint when you need to encode or decode text specifically using the rail fence (zigzag) transposition cipher, especially for CTF challenges, cryptography education, or puzzle-making. It supports configurable rails (2–20) and optionally preserves spaces and punctuation. Prefer it over Caesar or Vigenere endpoints when the cipher type is specifically a columnar/rail transposition rather than a substitution cipher.

• Missing required 'text' or 'rails' parameter returns an error
• Rails value outside 2–20 range may return a validation error
• Text exceeding 1000 characters may be rejected
• Invalid mode value (not 'encode' or 'decode') may cause unexpected behavior
• Non-alphanumeric characters silently stripped unless 'raw=true' is set