mqtt-monitor-all

name	mqtt-monitor-all
description	Subscribe to all MQTT topics (`#`) on the configured broker and stream payloads for observation. Use when the user wants to see every message flowing through their broker, sniff activity, or find which topic a device publishes to. Requires `/mqtt-setup` to have been run previously.

Monitor all MQTT payloads

Subscribe to the wildcard topic # on the user's configured broker and stream incoming messages.

Load credentials

Before anything else, source the credentials file:

if [ ! -f ~/.claude/plugins-data/mqtt-observability/credentials.env ]; then
  echo "No MQTT credentials found. Run /mqtt-setup first." >&2
  exit 1
fi
set -a; . ~/.claude/plugins-data/mqtt-observability/credentials.env; set +a

Subscribe

Use mosquitto_sub with verbose mode so topic names are printed alongside payloads:

mosquitto_sub -h "$MQTT_HOST" -p "$MQTT_PORT" \
  ${MQTT_USERNAME:+-u "$MQTT_USERNAME"} \
  ${MQTT_PASSWORD:+-P "$MQTT_PASSWORD"} \
  -t '#' -v

How to run it

Because this is a streaming command, run it with run_in_background: true and then use Monitor (or read the background output) to collect payloads. Ask the user how long to watch (default: 30 seconds) and then stop the background job.

If the user asks for a bounded capture, prefer timeout 30 mosquitto_sub ... so the command exits cleanly.

Output to the user

Summarise what was seen:

• Distinct topics observed
• Message rate per topic (approx)
• Any notable payloads (JSON decoded if possible)

Don't dump thousands of raw lines into the conversation — group and summarise.

Dependency

Requires mosquitto-clients. If missing, tell the user:

sudo apt install mosquitto-clients