Constant LOGIN_PTY_COLS 

pub const LOGIN_PTY_COLS: u16 = 4096;

Columns for a login PTY. Wide enough that the CLI’s own line-wrapping never wraps the OAuth URL. At 80 cols it did — Claude Code prints “If the browser didn’t open, visit: ” as plain text and hard-wraps it mid-query-string, so only a truncated fragment missing client_id and everything after it was captured (issue #2429). 4096 comfortably covers any realistic query string.