MQTTX CLI

Prepare

1. Locate mqttx, read mqttx --version, then inspect mqttx <command> --help for the task. Treat installed help as authoritative; release channels can differ. If missing or a required feature is unavailable, follow the repository's root INSTALL.md, or its standalone installation guide when this skill has been copied elsewhere. Do not update a working CLI on every invocation.
2. Establish the broker hostname, port, transport (mqtt, mqtts, ws, wss), MQTT version, credentials, topic and intended operation from the user's context. Ask only for missing information that affects execution. Use the requested broker; do not substitute a public broker after a failure.
3. Account for ~/.mqttx-cli/config, which can supply default host, port, protocol and credentials. Do not print its secrets or overwrite it for a one-off task. Explicit CLI arguments override defaults; --load-options loads command-specific JSON/YAML options, with explicitly supplied CLI arguments taking precedence. See configuration and utility commands for initialization, saving and loading.
4. Set a finite observation deadline for connection/subscription tasks and retain a handle to each process started. Use the agent's process controller or an available OS timeout tool; a tool returning a session handle is not necessarily a deadline. Terminate and wait for owned processes at completion or timeout.

The CLI command registration in this repository (1.13.0) does not offer general --timeout, --max-messages, --json or --output jsonl flags. Do not invent them. Recheck help for other versions. --reconnect-period 0 disables reconnection; it is not an overall deadline. conn stays connected after success and sub keeps listening until stopped.

Choose a workflow

This skill covers every command registered in the repository's CLI 1.13.0, including command-specific limitations. Read only the references relevant to the task. Coverage describes how to operate available features; it does not make unsupported combinations work or guarantee every broker implements them.