Errors

Library functions return micro_wakeword::Result<T>, an alias for Result<T, micro_wakeword::Error>.

Variant	Meaning	Usually recoverable?
Io { path, source }	Could not read a config/model-related file	After correcting path or permissions
Json { path, source }	Configuration is not valid JSON	After fixing the file
InvalidConfig(message)	Values violate the supported contract	After changing configuration
IncompatibleModel(message)	Tensor shape/type is unsupported	Use a compatible model
Tflite(error)	Native runtime or inference failed	Depends on native error
UnsupportedPlatform(message)	No usable runtime on this platform	Supply a runtime
Audio(message)	Device open, format, or stream failure	Often; device may become available
AudioStreamEnded	Capture channel ended	Often; recreate listener

Match errors deliberately

use micro_wakeword::{Error, Listener};

fn open() {
    match Listener::from_config("wake-word.json") {
        Ok(_) => println!("Ready"),
        Err(Error::Audio(message)) => eprintln!("Microphone: {message}"),
        Err(Error::AudioStreamEnded) => eprintln!("Microphone stream ended"),
        Err(Error::InvalidConfig(message)) => eprintln!("Settings: {message}"),
        Err(error) => eprintln!("Could not start: {error}"),
    }
}

Applications normally retry only transient microphone failures. Retrying malformed JSON or an incompatible model forever hides a deployment problem and wastes resources.

For command-line tools, returning Result<(), Box<dyn Error>> from main is concise. User-facing apps should translate variants into clear UI and preserve the source error in logs.