configure

/mqtt:configure — MQTT Channel Setup

Writes connection settings to ~/.claude/channels/mqtt/.env and orients the user on subscription and access policy. The server reads .env at boot.

Arguments passed: $ARGUMENTS

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Dispatch on arguments

No args — status and guidance

Read the state files and give the user a complete picture:

1. Broker URL — check ~/.claude/channels/mqtt/.env for MQTT_BROKER_URL. Show set/not-set; if set, show the URL with password masked if embedded in the URL.

2. Auth — check for MQTT_USERNAME in .env. Show set/not-set. Never display the password.

3. Client ID — check for MQTT_CLIENT_ID in .env. Show if set, otherwise mention the default prefix claude-mqtt.

4. Subscriptions — read ~/.claude/channels/mqtt/config.json if it exists. Show subscription count and list topics. Show allowlist state.

5. What next — end with a concrete next step based on state:

   • No broker URL → "Run /mqtt:configure <broker-url> with your MQTT broker URL (e.g., mqtt://localhost:1883)."
   • URL set, no subscriptions → "Add subscriptions with /mqtt:access subscribe add <topic>."
   • URL set, subscriptions present → "Ready. Launch with claude --channels plugin:mqtt@apoco-plugins to start receiving messages."

<broker-url> — save it

Detect this case when $ARGUMENTS starts with mqtt:// or mqtts://.

1. Treat $ARGUMENTS as the broker URL (trim whitespace). Validate it starts with mqtt:// or mqtts://.
2. mkdir -p ~/.claude/channels/mqtt
3. Read existing .env if present; update/add the MQTT_BROKER_URL= line, preserve other keys. Write back, no quotes around the value.
4. chmod 600 ~/.claude/channels/mqtt/.env — the URL may contain credentials.
5. Confirm, then show the no-args status so the user sees where they stand.

auth <username> <password> — save credentials

1. Parse username and password from $ARGUMENTS (after "auth").
2. mkdir -p ~/.claude/channels/mqtt
3. Read existing .env if present; update/add MQTT_USERNAME= and MQTT_PASSWORD= lines, preserve other keys. Write back.
4. chmod 600 ~/.claude/channels/mqtt/.env
5. Confirm credentials saved. Remind user to restart session.

client-id <prefix> — set client ID prefix

1. Parse the prefix from $ARGUMENTS (after "client-id").
2. mkdir -p ~/.claude/channels/mqtt
3. Read existing .env; update/add MQTT_CLIENT_ID= line. Write back.
4. chmod 600 ~/.claude/channels/mqtt/.env
5. Confirm.

clear — remove credentials

Delete MQTT_BROKER_URL=, MQTT_USERNAME=, MQTT_PASSWORD=, and MQTT_CLIENT_ID= lines from .env (or the file if those are the only lines).

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Implementation notes

• The channels dir might not exist if the server hasn't run yet. Missing file = not configured, not an error.
• The server reads .env once at boot. Changes need a session restart or /reload-plugins. Say so after saving.
• config.json is re-read on every tool call — subscription/allowlist changes via /mqtt:access take effect immediately, no restart.