List the serial ports currently present on this machine.

Use the description, manufacturer and vid/pid fields to identify the board (e.g. 0x10C4:0xEA60 = CP210x on many ESP32 dev kits, 0x2341 = Arduino, 0x1A86 = CH340). On macOS prefer the /dev/cu.* entry over /dev/tty.*.

Open a serial port and start buffering everything it sends.

Idempotent: opening an already-open port with the same settings just returns its status; different settings close and reopen it. The port stays open until close_port.

Close a port opened with open_port and release it for other programs.

Show open ports with byte counters, buffered (unread) bytes and disconnect errors.

Send raw bytes without waiting for a reply (use query for request/response).

Read and consume buffered data from the device (logs, sensor output, late replies).

Wait until a pattern appears (e.g. 'OK', 'ready>', 'Temperature:') and return everything up to and including it. On timeout returns whatever arrived, with matched=false.

Send a command and return its reply in one call. Best for request/response devices (AT modems, CLI firmware, 'PING' -> 'PONG' sketches).

Peek at the last lines received on a port WITHOUT consuming the read buffer. Good for checking what a device has been printing while you were doing other things.

Discard all buffered unread data on a port (line history for tail is kept).

Reboot the board by pulsing DTR/RTS and return what it prints while booting. Only works on boards that wire those lines to reset (most USB dev boards do).

Set the DTR / RTS modem control lines manually (bootloader entry, custom reset circuits).