Headless collection

Without a TTY - or when prompts are supplied - the same form collects non-interactively: answers come from a JSON payload (a string or a path to a file), per-question environment overrides and the declared defaults, with derives, conditions and fix-ups settled exactly as in the TUI.

$answers = $tui->collect('{"name":"Ada"}');
$answers = $tui->run($prompts, '1.0.0'); // TUI on a terminal, headless otherwise.

Environment overrides are named <PREFIX><FIELD_ID> (the uppercased field id). ->envPrefix('MYAPP_') declares that namespace on the form, a new Tui($form, env_prefix: 'MYAPP_') constructor argument overrides it, and without either the prefix is TUI_:

MYAPP_TIMEZONE=UTC php my-installer.php

For automation and AI agents, the form describes itself: schema() emits a JSON schema of the questions, agentHelp() a plain-text guide for driving the form non-interactively, and validate($answers) checks a payload against the schema before collection.

Each of these has a runnable script in playground/05-headless/.